draft-ietf-webdav-protocol-06.txt   draft-ietf-webdav-protocol-07.txt 
WEBDAV Working Group Y.Y. Goland, Microsoft WEBDAV Working Group Y.Y. Goland, Microsoft
INTERNET DRAFT E.J. Whitehead, Jr., UC Irvine INTERNET DRAFT E.J. Whitehead, Jr., UC Irvine
<draft-ietf-webdav-protocol-06> A. Faizi, Netscape <draft-ietf-webdav-protocol-07> A. Faizi, Netscape
S.R. Carter, Novell S.R. Carter, Novell
D. Jensen, Novell D. Jensen, Novell
Expires July, 1998 January 18, 1998 Expires August, 1998 March 6, 1998
Extensions for Distributed Authoring on the World Wide Web -- WEBDAV Extensions for Distributed Authoring on the World Wide Web -- WEBDAV
Status of this Memo Status of this Memo
This document is an Internet-Draft. Internet-Drafts are working This document is an Internet-Draft. Internet-Drafts are working
documents of the Internet Engineering Task Force (IETF), its areas, documents of the Internet Engineering Task Force (IETF), its areas,
and its working groups. Note that other groups may also distribute and its working groups. Note that other groups may also distribute
working documents as Internet-Drafts. working documents as Internet-Drafts.
skipping to change at page 1, line 45 skipping to change at page 2, line 5
Discussions of the WEBDAV working group are archived at Discussions of the WEBDAV working group are archived at
<URL:http://www.w3.org/pub/WWW/Archives/Public/w3c-dist-auth>. <URL:http://www.w3.org/pub/WWW/Archives/Public/w3c-dist-auth>.
Abstract Abstract
This document specifies a set of methods, headers, and content-types This document specifies a set of methods, headers, and content-types
ancillary to HTTP/1.1 for the management of resource properties, ancillary to HTTP/1.1 for the management of resource properties,
creation and management of resource collections, namespace creation and management of resource collections, namespace
manipulation, and resource locking (collision avoidance). manipulation, and resource locking (collision avoidance).
Changes
Changes since draft-ietf-webdav-protocol-06.txt
[Editor's note: This section will not appear in the final form of
this document. Its purpose is to provide a concise list of changes
from the previous revision of the draft for use by reviewers.]
Rationale for many of the changes made in this revision of the draft
can be found in the mailing list archives at:
http://lists.w3.org/Archives/Public/w3c-dist-auth/1997OctDec/0160.ht
ml.
Where the 200 OK status code was used to indicate a successful
response without a response entity body, 204 No Content is now used.
Because PEP uses 420 and 421 status codes, and since PEP has been
submitted as an Experimental RFC, the WebDAV 420 status code has
been changed to 422, and the WebDAV 421 status code has been changed
to 423.
The 423 Destination Locked status code has been changed to 423
Locked, and now covers all cases where an operand was locked,
preventing the execution of the method.
Removed the Destroy header, since it is not needed in this draft,
but will be needed in the versioning draft.
The Enforce-Live-Properties header was renamed to Property-Behavior,
to more closely represent the meaning of the header now that the
"omit" functionality is included. A keepalive field was added to the
Property-Behavior header to make it more meaningful.
Removed the INDEX method, since the functionality of INDEX can now
be performed by the PROPFIND method. PROPFIND provides more
flexibility in specifying the type and amount of property
information returned than does INDEX, which is important for
returning information on a large number of resources.
Clarified that performing a MOVE as a COPY, then DELETE, performed
atomically, only applies to non-collection resources.
Clarified the semantics of errors that are encountered in infinite
depth move and copy of a hierarchy of resources. For errors copying
internal nodes of the hierarchy tree (i.e., collections), the
operation skips that subtree, and moves on to the next subtree. If
an error is encountered moving/copying a leaf of the tree, then skip
that resource, and move on to the next leaf.
Removed the PATCH method. This will be resubmitted as the document
draft-ietf-webdav-patch-00.
Added language that states that if a PROPPATCH is invoked on a null
resource (e.g., a deleted resource), an empty resource is created,
and the PROPPATCH directives are performed on this new resource.
Added a forward reference to the source link definition (Section
13.11) in Section 4.4.
Changed all Values= to Values:. Also changed all "values" to
"value".
References to state tokens are now restricted to sections 9.7 and
9.8.
The property-behavior header has been turned into the
propertybehavior XML element because it contained a list of URIs
which can thus have unbounded size. The lock-info header has been
turned into the lockinfo XML element for the same reason. I have
also made the same change of the Propfind header into the Propfind
XML element. We can put the property behavior header into the body
because neither COPY nor MOVE have bodies. However we can't put
lock-token, if-state-match, etc. in the body because they may need
to be used with PUT. However I don't consider this a big deal
because I sincerely doubt that there will be cases where lock-token
or if-state-match will see large numbers of entries.
Also changed omit to mean "copy properties with best effort but
failure is acceptable."
Added the external members property.
Added language to 6.4 making it clear that any new resources created
as the child of a write locked collection is added to the lock.
Made the lock-token response header from a single URL to multiple
URLs. But all the URLs MUST refer to the exact same lock.
<?XML version="1.0"> changed to the correct form: <?xml
version="1.0"?>
Changed the delete rule for collections to read that if a delete in
a collection member fails then it is the ancestors, not the progeny,
who can not be deleted in order to maintain the namespace.
Updated our reference to the XML spec.
Added LOCK and UNLOCK to the list of methods covered by the write
lock. This is necessary so that a lock-token will have to be
submitted in order to make changes, otherwise we defeat the whole
purpose of requiring the lock-token.
Changed the title of section 6.6 from Re-Issuing Write Locks to
Refreshing Write Locks, made it illegal to make the same lock
request twice (you know you are making the same request because you
had to include the lock-token to make it!) and instead made it legal
to submit a LOCK method with no body but with a lock-token header.
I also added a refresh example.
Put in a note that an empty request body for PROPFIND means to
return all names and values of properties on the resources.
I have added a section on XML processing errors. I know, I know, it
shouldn't be in the standard. I will move it to our compliance draft
as soon as we prepare the first version.
Removed addlocks and replaced with the depth header and the depth
element.
Changed all the as in namespace elements to all lower case.
Moved all XML element declarations to the same section. Removed the
parent description.
Updated the depth section to make it more generic, changed the
wording for how COPY/MOVE are handled with write locks, require that
ALL propfind responses include href, require that if a property is
not found in a propfind then a 404 Not Found must be returned, and
made explicit that PROPFIND responses on resources with internal
members are returned as a flat list with no significance to its
ordering.
Removed reference to efficient update in the introduction since
PATCH is now gone.
Rewrote the write lock and null resource section to deal with the
question of the state of the resource when it is locked and null.
Changed www.ietf.org to www.iana.org.
Changed the response element and added the new propstat element.
With the prohibition that an HREF can only appear once in a
multistatus response we can guarantee linear processing costs.
Added Intellectual Property section, as required by RFC 2026.
Added IANA Considerations section.
Added Authorization headers to LOCK and UNLOCK examples.
Changed lock tokens in examples to use string format of UUID.
Since the latest HTTP revision defines a 418 and 419 status code,
the 418 status code has been changed to 422, 419 to 423, 422 to 424,
and 423 to 425.
Changed implementation of the get* (e.g., getcontentlength)
properties to strength MUST.
Changed definition of XML elements and DAV properties to use XML
element definitions, rather than BNF.
Renumbered all sections
Contents Contents
STATUS OF THIS MEMO..................................................1 STATUS OF THIS MEMO..................................................1
ABSTRACT.............................................................1 ABSTRACT.............................................................1
CHANGES..............................................................1 CONTENTS.............................................................2
Changes since draft-ietf-webdav-protocol-06.txt......................1 1 INTRODUCTION.......................................................7
CONTENTS.............................................................5 2 NOTATIONAL CONVENTIONS.............................................8
1 INTRODUCTION.......................................................9 3 DATA MODEL FOR RESOURCE PROPERTIES.................................8
2 DATA MODEL FOR RESOURCE PROPERTIES................................10 3.1 The Resource Property Model.....................................8
2.1 The Resource Property Model....................................10 3.2 Existing Metadata Proposals.....................................9
2.2 Existing Metadata Proposals....................................10 3.3 Properties and HTTP Headers....................................10
2.3 Properties and HTTP Headers....................................11 3.4 Property Values................................................10
2.4 Property Values................................................11 3.5 Property Names.................................................10
2.5 Property Names.................................................12 3.6 Media Independent Links........................................11
3 COLLECTIONS OF WEB RESOURCES......................................12 4 COLLECTIONS OF WEB RESOURCES......................................11
3.1 Collection Resources...........................................12 4.1 Collection Resources...........................................11
3.2 Creation and Retrieval of Collection Resources.................13 4.2 Creation and Retrieval of Collection Resources.................12
3.3 HTTP URL Namespace Model.......................................13 4.3 HTTP URL Namespace Model.......................................12
3.4 Source Resources and Output Resources..........................14 4.4 Source Resources and Output Resources..........................12
4 LOCKING...........................................................15 5 LOCKING...........................................................13
4.1 Exclusive Vs. Shared Locks.....................................15 5.1 Exclusive Vs. Shared Locks.....................................14
4.2 Required Support...............................................16 5.2 Required Support...............................................15
4.3 Lock Tokens....................................................16 5.3 Lock Tokens....................................................15
4.4 opaquelocktoken Lock Token URI Scheme..........................17 5.4 opaquelocktoken Lock Token URI Scheme..........................15
4.5 Lock Capability Discovery......................................17 5.5 Lock Capability Discovery......................................16
4.6 Active Lock Discovery..........................................18 5.6 Active Lock Discovery..........................................16
5 WRITE LOCK........................................................18 5.7 Usage Considerations...........................................16
5.1 Methods Restricted by Write Locks..............................18 6 WRITE LOCK........................................................17
5.2 Write Locks and Properties.....................................18 6.1 Methods Restricted by Write Locks..............................17
5.3 Write Locks and Null Resources.................................18 6.2 Write Locks and Properties.....................................18
5.4 Write Locks and Collections....................................19 6.3 Write Locks and Null Resources.................................18
5.5 Write Locks and COPY/MOVE......................................19 6.4 Write Locks and Collections....................................18
5.6 Refreshing Write Locks.........................................19 6.5 Write Locks and the If Request Header..........................19
5.7 Write Locks and The Lock-Token Request Header..................20 6.5.1Write Lock Example............................................19
5.7.1 Write Lock Token Example...................................20 6.6 Write Locks and COPY/MOVE......................................19
6 NOTATIONAL CONVENTIONS............................................21 6.7 Refreshing Write Locks.........................................20
7 HTTP METHODS FOR DISTRIBUTED AUTHORING............................21 7 HTTP METHODS FOR DISTRIBUTED AUTHORING............................20
7.1 PROPFIND.......................................................21 7.1 PROPFIND.......................................................21
7.1.1 Example: Retrieving Named Properties.......................22 7.1.1 Example: Retrieving Named Properties.........................22
7.1.2 Example: Using allprop to Retrieve All Properties..........23 7.1.2 Example: Using allprop to Retrieve All Properties............23
7.1.3 Example: Using propname to Retrieve all Property Names.....26 7.1.3 Example: Using propname to Retrieve all Property Names.......26
7.2 PROPPATCH......................................................28 7.2 PROPPATCH......................................................27
7.2.1 Status Codes...............................................28 7.2.1 Status Codes for use with Multi-Status.......................28
7.2.2 Example....................................................28 7.2.2 Example......................................................28
7.3 MKCOL Method...................................................30 7.3 MKCOL Method...................................................29
7.3.1 Request....................................................30 7.3.1 Request......................................................29
7.3.2 Response Codes.............................................30 7.3.2 Response Codes...............................................30
7.3.3 Example....................................................31 7.3.3 Example......................................................30
7.4 ADDREF Method..................................................31 7.4 GET, HEAD for Collections......................................31
7.4.1 The Request................................................31 7.5 POST for Collections...........................................31
7.4.2 Example....................................................31 7.6 DELETE.........................................................31
7.5 DELREF Method..................................................32 7.6.1 DELETE for Non-Collection Resources..........................31
7.5.1 The Request................................................32 7.6.2 DELETE for Collections.......................................31
7.5.2 Example....................................................32 7.7 PUT............................................................32
7.6 GET, HEAD for Collections......................................32 7.7.1 PUT for Non-Collection Resources.............................32
7.7 POST for Collections...........................................33 7.7.2 PUT for Collections..........................................33
7.8 DELETE.........................................................33 7.8 COPY Method....................................................33
7.8.1 DELETE for Non-Collection Resources........................33 7.8.1 COPY for HTTP/1.1 resources..................................33
7.8.2 DELETE for Collections.....................................33 7.8.2 COPY for Properties..........................................34
7.9 PUT............................................................34 7.8.3 COPY for Collections.........................................34
7.9.1 PUT for Non-Collection Resources...........................34 7.8.4 COPY and the Overwrite Header................................35
7.9.2 PUT for Collections........................................35 7.8.5 Status Codes.................................................35
7.10 COPY Method....................................................35 7.8.6 Overwrite Example............................................35
7.10.1 COPY for HTTP/1.1 resources................................35 7.8.7 No Overwrite Example.........................................36
7.10.2 COPY for Properties........................................35 7.8.8 Collection Example...........................................36
7.10.3 COPY for Collections.......................................36 7.9 MOVE Method....................................................37
7.10.4 Type Interactions..........................................37 7.9.1 MOVE for Properties..........................................37
7.10.5 Status Codes...............................................37 7.9.2 MOVE for Collections.........................................38
7.10.6 Overwrite Example..........................................38 7.9.3 MOVE and the Overwrite Header................................38
7.10.7 No Overwrite Example.......................................38 7.9.4 Status Codes.................................................39
7.10.8 Collection Example.........................................38 7.9.5 Non-Collection Example.......................................39
7.11 MOVE Method....................................................39 7.9.6 Collection Example...........................................39
7.11.1 MOVE for Collections.......................................40 7.10 LOCK Method....................................................40
7.11.2 Status Codes...............................................40 7.10.1 Operation...................................................40
7.11.3 Non-Collection Example.....................................41 7.10.2 The Effect of Locks on Properties and Collections...........41
7.11.4 Collection Example.........................................41 7.10.3 Locking Replicated Resources................................41
7.12 LOCK Method....................................................42 7.10.4 Depth and Locking...........................................41
7.12.1 Operation..................................................43 7.10.5 Interaction with other Methods..............................42
7.12.2 The Effect of Locks on Properties and Collections..........43 7.10.6 Lock Compatibility Table....................................42
7.12.3 Locking Replicated Resources...............................43 7.10.7 Status Codes................................................42
7.12.4 Depth and Locking..........................................43 7.10.8 Example - Simple Lock Request...............................43
7.12.5 Interaction with other Methods.............................44 7.10.9 Example - Refreshing a Write Lock...........................44
7.12.6 Lock Compatibility Table...................................44 7.10.10 Example - Multi-Resource Lock Request......................45
7.12.7 Lock Response..............................................44 7.11 UNLOCK Method..................................................46
7.12.8 Status Codes...............................................44 7.11.1 Example.....................................................46
7.12.9 Example - Simple Lock Request..............................45 8 HTTP HEADERS FOR DISTRIBUTED AUTHORING............................47
7.12.10 Example - Refreshing a Write Lock.........................46 8.1 DAV Header.....................................................47
7.12.11 Example - Multi-Resource Lock Request.....................47 8.2 Depth Header...................................................47
7.13 UNLOCK Method..................................................48 8.3 Destination Header.............................................48
7.13.1 Example....................................................48 8.4 If Header......................................................48
8 HTTP HEADERS FOR DISTRIBUTED AUTHORING............................49 8.4.1 No-tag-list Production.......................................49
8.4.2 Tagged-list Production.......................................49
8.1 Collection-Member Header.......................................49 8.4.3 not Production...............................................50
8.2 DAV Header.....................................................49 8.4.4 Matching Function............................................50
8.3 Depth Header...................................................49 8.4.5 If Header and Non-DAV Compliant Proxies......................50
8.4 Destination Header.............................................50 8.5 Lock-Token Request Header......................................51
8.5 If-None-State-Match............................................50 8.6 Overwrite Header...............................................51
8.6 If-State-Match.................................................51 8.7 Status-URI Response Header.....................................51
8.7 Lock-Token Request Header......................................51 8.8 Timeout Request Header.........................................52
8.8 Lock-Token Response Header.....................................52 9 STATUS CODE EXTENSIONS TO HTTP/1.1................................53
8.9 Overwrite Header...............................................53 9.1 102 Processing.................................................53
8.10 Status-URI Response Header.....................................53 9.2 207 Multi-Status...............................................53
8.11 Timeout Header.................................................53 9.3 422 Unprocessable Entity.......................................53
9 STATUS CODE EXTENSIONS TO HTTP/1.1................................54 9.4 423 Locked.....................................................53
9.1 102 Processing.................................................54 9.5 424 Method Failure.............................................53
9.2 207 Multi-Status...............................................55 9.6 425 Insufficient Space on Resource.............................53
9.3 422 Unprocessable Entity.......................................55 10 MULTI-STATUS RESPONSE............................................53
9.4 423 Insufficient Space on Resource.............................55 11 XML ELEMENT DEFINITIONS..........................................54
9.5 424 Method Failure.............................................55 11.1 activelock XML Element.........................................54
9.6 425 Locked.....................................................55 11.1.1 depth XML Element...........................................54
10 MULTI-STATUS RESPONSE...........................................55 11.1.2 locktoken XML Element.......................................54
11 XML ELEMENT DEFINITIONS.........................................55 11.1.3 timeout XML Element.........................................54
11.1 activelock XML Element.........................................56 11.2 collection XML Element.........................................55
11.1.1 depth XML Element..........................................56 11.3 href XML Element...............................................55
11.1.2 locktoken XML Element......................................56 11.4 link XML Element...............................................55
11.1.3 timeout XML Element........................................56 11.4.1 dst XML Element.............................................55
11.2 collection XML Element.........................................56 11.4.2 src XML Element.............................................55
11.3 href XML Element...............................................56 11.5 lockentry XML Element..........................................56
11.4 link XML Element...............................................57 11.6 lockinfo XML Element...........................................56
11.4.1 dst XML Element............................................57 11.7 lockscope XML Element..........................................56
11.4.2 src XML Element............................................57 11.7.1 exclusive XML Element.......................................56
11.5 lockentry XML Element..........................................57 11.7.2 shared XML Element..........................................56
11.6 lockinfo XML Element...........................................57 11.8 locktype XML Element...........................................56
11.7 lockscope XML Element..........................................58 11.8.1 write XML Element...........................................57
11.7.1 exclusive XML Element......................................58 11.9 multistatus XML Element........................................57
11.7.2 shared XML Element.........................................58 11.9.1 response XML Element........................................57
11.8 locktype XML Element...........................................58 11.9.2 responsedescription XML Element.............................58
11.8.1 write XML Element..........................................58 11.10 owner XML Element.............................................58
11.9 multistatus XML Element........................................58 11.11 prop XML element..............................................58
11.9.1 response XML Element.......................................59 11.12 propertybehavior XML element..................................58
11.9.2 responsedescription XML Element............................59 11.12.1 keepalive XML element......................................59
11.10 owner XML Element.............................................60 11.12.2 omit XML element...........................................59
11.11 prop XML element..............................................60 11.13 propertyupdate XML element....................................59
11.12 propertybehavior XML element..................................60 11.13.1 remove XML element.........................................60
11.12.1 keepalive XML element.....................................60 11.13.2 set XML element............................................60
11.12.2 omit XML element..........................................61 11.14 propfind XML Element..........................................60
11.13 propertyupdate XML element....................................61 11.14.1 allprop XML Element........................................60
11.13.1 remove XML element........................................61 11.14.2 propname XML Element.......................................61
11.13.2 set XML element...........................................62 12 DAV PROPERTIES...................................................61
11.14 propfind XML Element..........................................62 12.1 creationdate Property..........................................61
11.14.1 allprop XML Element.......................................62 12.2 displayname Property...........................................61
11.14.2 propname XML Element......................................62 12.3 getcontentlanguage Property....................................61
12 DAV PROPERTIES..................................................62 12.4 getcontentlength Property......................................62
12.1 creationdate Property..........................................63 12.5 getcontenttype Property........................................62
12.2 displayname Property...........................................63 12.6 getetag Property...............................................62
12.3 externalmembers Property.......................................63 12.7 getlastmodified Property.......................................63
12.4 getcontentlanguage Property....................................63 12.8 lockdiscovery Property.........................................63
12.5 getcontentlength Property......................................64 12.8.1 Example.....................................................63
12.6 getcontenttype Property........................................64 12.9 resourcetype Property..........................................64
12.7 getetag Property...............................................64 12.10 source Property...............................................64
12.8 getlastmodified Property.......................................64 12.10.1 Example....................................................65
12.9 lockdiscovery Property.........................................65 12.11 supportedlock Property........................................66
12.9.1 Example....................................................65 12.11.1 Example....................................................66
12.10 resourcetype Property.........................................66 13 DAV XML PROCESSING INSTRUCTIONS..................................67
12.11 source Property...............................................66 14 DAV COMPLIANCE CLASSES...........................................67
12.11.1 Example...................................................67 14.1 Class 1........................................................67
12.12 supportedlock Property........................................67 14.2 Class 2........................................................68
12.12.1 Example...................................................68 15 INTERNATIONALIZATION CONSIDERATIONS..............................68
13 DAV COMPLIANCE CLASSES..........................................68 16 SECURITY CONSIDERATIONS..........................................69
13.1 Class 1........................................................69 16.1 Authentication of Clients......................................69
13.2 Class 2........................................................69 16.2 Denial of Service..............................................70
14 INTERNATIONALIZATION CONSIDERATIONS.............................69 16.3 Security through Obscurity.....................................70
15 SECURITY CONSIDERATIONS.........................................70 16.4 Privacy Issues Connected to Locks..............................70
15.1 Authentication of Clients......................................71 16.5 Privacy Issues Connected to Properties.........................70
15.2 Denial of Service..............................................71 16.6 Reduction of Security due to Source Link.......................71
15.3 Security through Obscurity.....................................72 17 IANA CONSIDERATIONS..............................................71
15.4 Privacy Issues Connected to Locks..............................72 18 TERMINOLOGY......................................................72
15.5 Privacy Issues Connected to Properties.........................72 19 COPYRIGHT........................................................72
15.6 Reduction of Security due to Source Link.......................72 20 INTELLECTUAL PROPERTY............................................73
16 IANA CONSIDERATIONS.............................................73 21 ACKNOWLEDGEMENTS.................................................73
17 TERMINOLOGY.....................................................73 22 REFERENCES.......................................................75
18 COPYRIGHT.......................................................74 23 AUTHORS' ADDRESSES...............................................77
19 INTELLECTUAL PROPERTY...........................................74 24 APPENDICES.......................................................78
20 ACKNOWLEDGEMENTS................................................75 24.1 Appendix 1 - WebDAV Document Type Definition...................78
21 REFERENCES......................................................76 24.2 Appendix 2 - ISO 8601 Date and Time Profile....................79
22 AUTHORS' ADDRESSES..............................................78 24.3 Appendix 3 - Notes on Processing XML Elements..................80
23 APPENDICES......................................................79 24.3.1 XML Syntax Error Example....................................80
23.1 Appendix 1 - WebDAV Document Type Definition...................79 24.3.2 Unknown XML Element Example.................................81
23.2 Appendix 2 - ISO 8601 Date and Time Profile....................80 24.4 Appendix 4 -- XML Namespaces for WebDAV........................82
23.3 Appendix 3 - Notes on Processing XML Elements..................81 24.4.1 Introduction................................................82
23.3.1 XML Syntax Error Example...................................81 24.4.2 Namespace Declaration PI....................................83
23.3.2 Unknown XML Element Example................................81 24.4.3 Prolog with Namespace Declarations..........................83
24.4.4 Well-Formedness Constraint - Unique Namespace Names.........83
24.4.5 Qualified Names.............................................83
24.4.6 Well-Formedness Constraint - Namespace Name Declared........83
24.4.7 Using Qualified Names.......................................84
24.4.8 Element Names...............................................84
24.4.9 Scope and Meaning of Qualified Names........................84
1 Introduction 1 Introduction
This document describes an extension to the HTTP/1.1 protocol that This document describes an extension to the HTTP/1.1 protocol that
allows clients to perform remote web content authoring operations. allows clients to perform remote web content authoring operations.
This extension provides a coherent set of methods, headers, request This extension provides a coherent set of methods, headers, request
entity body formats, and response entity body formats that provide entity body formats, and response entity body formats that provide
operations for: operations for:
Properties: The ability to create, remove, and query information Properties: The ability to create, remove, and query information
about Web pages, such as their authors, creation dates, etc. Also, about Web pages, such as their authors, creation dates, etc. Also,
the ability to link pages of any media type to related pages. the ability to link pages of any media type to related pages.
Collections: The ability to create sets of related documents, and to Collections: The ability to create sets of related documents and to
receive a listing of pages at a particular hierarchy level (like a retrieve a hierarchical membership listing (like a directory listing
directory listing in a file system). in a file system).
Locking: The ability to keep more than one person from working on a Locking: The ability to keep more than one person from working on a
document at the same time. This prevents the "lost update problem," document at the same time. This prevents the "lost update problem,"
in which modifications are lost as first one author, then another in which modifications are lost as first one author then another
writes changes without merging the other author's changes writes changes without merging the other author's changes.
Namespace Operations: The ability to copy and move Web resources Namespace Operations: The ability to instruct the server to copy and
move Web resources.
Requirements and rationale for these operations are described in a Requirements and rationale for these operations are described in a
companion document, "Requirements for a Distributed Authoring and companion document, "Requirements for a Distributed Authoring and
Versioning Protocol for the World Wide Web" [Slein et al., 1997]. Versioning Protocol for the World Wide Web" [Slein et al., 1998].
The sections below provide a detailed introduction to resource The sections below provide a detailed introduction to resource
properties (Section 2), collections of resources (Section 3), and properties (section 3), collections of resources (section 4), and
locking operations (Section 4). These sections introduce the locking operations (section 5). These sections introduce the
abstractions manipulated by the WebDAV-specific HTTP methods abstractions manipulated by the WebDAV-specific HTTP methods
described in Section 7, "HTTP Methods for Distributed Authoring". described in section 7, "HTTP Methods for Distributed Authoring".
In HTTP/1.1, method parameter information was exclusively encoded in In HTTP/1.1, method parameter information was exclusively encoded in
HTTP headers. Unlike HTTP/1.1, WebDAV, encodes method parameter HTTP headers. Unlike HTTP/1.1, WebDAV, encodes method parameter
information either in an Extensible Markup Language (XML) [Bray, information either in an Extensible Markup Language (XML) [Bray,
Paoli, Sperberg-McQueen, 1998] request entity body, or in an HTTP Paoli, Sperberg-McQueen, 1998] request entity body, or in an HTTP
header. The use of XML to encode method parameters was motivated by header. The use of XML to encode method parameters was motivated by
the ability to add extra XML elements to existing structures, the ability to add extra XML elements to existing structures,
providing extensibility, and by XML's ability to encode information providing extensibility, and by XML's ability to encode information
in ISO 10646 character sets, providing internationalization support. in ISO 10646 character sets, providing internationalization support.
As a rule of thumb, parameters are encoded in XML entity bodies when As a rule of thumb, parameters are encoded in XML entity bodies when
they have unbounded length, or when they may be shown to a human they have unbounded length, or when they may be shown to a human
user and hence require encoding in an ISO 10646 character set. user and hence require encoding in an ISO 10646 character set.
Otherwise, parameters are encoded within HTTP headers. Section 8 Otherwise, parameters are encoded within HTTP headers. Section 8
describes the new HTTP headers used with WebDAV methods. describes the new HTTP headers used with WebDAV methods.
In addition to encoding method parameters, XML is used in WebDAV to In addition to encoding method parameters, XML is used in WebDAV to
encode the responses from methods, providing the extensibility and encode the responses from methods, providing the extensibility and
internationalization advantages of XML for method output, as well as internationalization advantages of XML for method output, as well as
input. XML elements used in this specification are defined in input.
Section 11.
XML elements used in this specification are defined in section 11.
The XML namespace extension (Appendix 4) is also used in this
specification in order to allow for new XML elements to be added
without fear of colliding with other element names.
While the status codes provided by HTTP/1.1 are sufficient to While the status codes provided by HTTP/1.1 are sufficient to
describe most error conditions encountered by WebDAV methods, there describe most error conditions encountered by WebDAV methods, there
are some errors that do not fall neatly into the existing are some errors that do not fall neatly into the existing
categories. New status codes developed for the WebDAV methods are categories. New status codes developed for the WebDAV methods are
defined in Section 9. Since some WebDAV methods may operate over defined in section 9. Since some WebDAV methods may operate over
many resources, the Multi-Status status type has been introduced to many resources, the Multi-Status response has been introduced to
return status information for multiple resources. Multi-Status return status information for multiple resources. The Multi-Status
response is described in Section 10. response is described in section 10.
WebDAV employs the property mechanism to store information about the WebDAV employs the property mechanism to store information about the
current state of the resource. For example, when a lock is taken current state of the resource. For example, when a lock is taken
out on a resource, a lock information property describes the current out on a resource, a lock information property describes the current
state of the lock. Section 12 defines the properties used within the state of the lock. Section 12 defines the properties used within the
WebDAV specification. WebDAV specification.
Finishing off the specification are sections on what it means to be Finishing off the specification are sections on what it means to be
compliant with this specification (Section 13), on compliant with this specification (section 14), on
internationalization support (Section 14), and on security (Section internationalization support (section 15), and on security (section
15). 16).
2 Data Model for Resource Properties 2 Notational Conventions
2.1 The Resource Property Model Since this document describes a set of extensions to the HTTP/1.1
protocol, the augmented BNF used herein to describe protocol
elements is exactly the same as described in section 2.1 of
[Fielding et al., 1997]. Since this augmented BNF uses the basic
production rules provided in section 2.2 of [Fielding et al., 1997],
these rules apply to this document as well.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [Bradner,
1997].
3 Data Model for Resource Properties
3.1 The Resource Property Model
Properties are pieces of data that describe the state of a resource. Properties are pieces of data that describe the state of a resource.
Properties are data about data. Properties are data about data.
Properties are used in distributed authoring environments to provide Properties are used in distributed authoring environments to provide
for efficient discovery and management of resources. For example, a for efficient discovery and management of resources. For example, a
'subject' property might allow for the indexing of all resources by 'subject' property might allow for the indexing of all resources by
their subject, and an 'author' property might allow for the their subject, and an 'author' property might allow for the
discovery of what authors have written which documents. discovery of what authors have written which documents.
The DAV property model consists of name/value pairs. The name of a The DAV property model consists of name/value pairs. The name of a
property identifies the property's syntax and semantics, and property identifies the property's syntax and semantics, and
provides an address by which to refer to that syntax and semantics. provides an address by which to refer to its syntax and semantics.
There are two categories of properties: "live" and "dead". A live There are two categories of properties: "live" and "dead". A live
property has its syntax and semantics enforced by the server. Live property has its syntax and semantics enforced by the server. Live
properties include cases where a) the value of a property is read- properties include cases where a) the value of a property is read-
only, maintained by the server, and b) the value of the property is only, maintained by the server, and b) the value of the property is
maintained by the client, but the server performs syntax checking on maintained by the client, but the server performs syntax checking on
submitted values. A dead property has its syntax and semantics submitted values. A dead property has its syntax and semantics
enforced by the client; the server merely records the value of the enforced by the client; the server merely records the value of the
property verbatim. property verbatim.
2.2 Existing Metadata Proposals 3.2 Existing Metadata Proposals
Properties have long played an essential role in the maintenance of Properties have long played an essential role in the maintenance of
large document repositories, and many current proposals contain some large document repositories, and many current proposals contain some
notion of a property, or discuss web metadata more generally. These notion of a property, or discuss web metadata more generally. These
include PICS [Miller et al., 1996], PICS-NG, XML [Bray, Paoli, include PICS [Miller et al., 1996], PICS-NG, XML, Web Collections,
Sperberg-McQueen, 1998], Web Collections, and several proposals on and several proposals on representing relationships within HTML.
representing relationships within HTML. Work on PICS-NG and Web Work on PICS-NG and Web Collections has been subsumed by the
Collections has been subsumed by the Resource Definition Framework Resource Definition Framework (RDF) metadata activity of the World
(RDF) metadata activity of the World Wide Web Consortium. RDF Wide Web Consortium. RDF consists of a network-based data model and
consists of a network-based data model and an XML representation of an XML representation of that model.
that model.
Some proposals come from a digital library perspective. These Some proposals come from a digital library perspective. These
include the Dublin Core [Weibel et al., 1995] metadata set and the include the Dublin Core [Weibel et al., 1995] metadata set and the
Warwick Framework [Lagoze, 1996], a container architecture for Warwick Framework [Lagoze, 1996], a container architecture for
different metadata schemas. The literature includes many examples different metadata schemas. The literature includes many examples
of metadata, including MARC [MARC, 1994], a bibliographic metadata of metadata, including MARC [MARC, 1994], a bibliographic metadata
format, and RFC 1807 [Lasher, Cohen, 1995], a technical report format, and RFC 1807 [Lasher, Cohen, 1995], a technical report
bibliographic format employed by the Dienst system. Additionally, bibliographic format employed by the Dienst system. Additionally,
the proceedings from the first IEEE Metadata conference describe the proceedings from the first IEEE Metadata conference describe
many community-specific metadata sets. many community-specific metadata sets.
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the proceedings from the first IEEE Metadata conference describe the proceedings from the first IEEE Metadata conference describe
many community-specific metadata sets. many community-specific metadata sets.
Participants of the 1996 Metadata II Workshop in Warwick, UK Participants of the 1996 Metadata II Workshop in Warwick, UK
[Lagoze, 1996], noted that "new metadata sets will develop as the [Lagoze, 1996], noted that "new metadata sets will develop as the
networked infrastructure matures" and "different communities will networked infrastructure matures" and "different communities will
propose, design, and be responsible for different types of propose, design, and be responsible for different types of
metadata." These observations can be corroborated by noting that metadata." These observations can be corroborated by noting that
many community-specific sets of metadata already exist, and there is many community-specific sets of metadata already exist, and there is
significant motivation for the development of new forms of metadata significant motivation for the development of new forms of metadata
as many communities increasingly make their data available in as many communities increasingly make their data available in
digital form, requiring a metadata format to assist data location digital form, requiring a metadata format to assist data location
and cataloging. and cataloging.
2.3 Properties and HTTP Headers 3.3 Properties and HTTP Headers
Properties already exist, in a limited sense, in HTTP message Properties already exist, in a limited sense, in HTTP message
headers. However, in distributed authoring environments a headers. However, in distributed authoring environments a
relatively large number of properties are needed to describe the relatively large number of properties are needed to describe the
state of a resource, and setting/returning them all through HTTP state of a resource, and setting/returning them all through HTTP
headers is inefficient. Thus a mechanism is needed which allows a headers is inefficient. Thus a mechanism is needed which allows a
principal to identify a set of properties in which the principal is principal to identify a set of properties in which the principal is
interested and to set or retrieve just those properties. interested and to set or retrieve just those properties.
2.4 Property Values 3.4 Property Values
The value of a property is expressed as a well-formed XML document. The value of a property is, at minimum, well formed XML.
XML has been chosen because it is a flexible, self-describing, XML has been chosen because it is a flexible, self-describing,
structured data format that supports rich schema definitions, and structured data format that supports rich schema definitions, and
because of its support for multiple character sets. XML's self- because of its support for multiple character sets. XML's self-
describing nature allows any property's value to be extended by describing nature allows any property's value to be extended by
adding new elements. Older clients will not break when they adding new elements. Older clients will not break when they
encounter extensions because they will still have the data specified encounter extensions because they will still have the data specified
in the original schema and will ignore elements they do not in the original schema and will ignore elements they do not
understand. XML's support for multiple character sets allows any understand. XML's support for multiple character sets allows any
human-readable property to be encoded and read in a character set human-readable property to be encoded and read in a character set
familiar to the user. familiar to the user.
2.5 Property Names 3.5 Property Names
A property name is a universally unique identifier that is A property name is a universally unique identifier that is
associated with a schema that provides information about the syntax associated with a schema that provides information about the syntax
and semantics of the property. and semantics of the property.
Because a property's name is universally unique, clients can depend Because a property's name is universally unique, clients can depend
upon consistent behavior for a particular property across multiple upon consistent behavior for a particular property across multiple
resources, so long as that property is "live" on the resources in resources, so long as that property is "live" on the resources in
question. question.
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is explicitly recognized. Thus, if a property A and a property A/B is explicitly recognized. Thus, if a property A and a property A/B
exist on a resource, there is no recognition of any relationship exist on a resource, there is no recognition of any relationship
between the two properties. It is expected that a separate between the two properties. It is expected that a separate
specification will eventually be produced which will address issues specification will eventually be produced which will address issues
relating to hierarchical properties. relating to hierarchical properties.
Finally, it is not possible to define the same property twice on a Finally, it is not possible to define the same property twice on a
single resource, as this would cause a collision in the resource's single resource, as this would cause a collision in the resource's
property namespace. property namespace.
3 Collections of Web Resources 3.6 Media Independent Links
Although HTML resources support links to other resources, the Web
needs more general support for links between resources of any media
type. WebDAV provides such links. A WebDAV link is a special type
of property value, formally defined in section 11.4, that allows
typed connections to be established between resources of any media
type. The property value consists of source and destination Uniform
Resource Locators (URLs); the property name identifies the link
type.
4 Collections of Web Resources
This section provides a description of a new type of Web resource, This section provides a description of a new type of Web resource,
the collection, and discusses its interactions with the HTTP Uniform the collection, and discusses its interactions with the HTTP URL
Resource Locator (URL) namespace. The purpose of a collection namespace. The purpose of a collection resource is to model
resource is to model collection-like objects (e.g., filesystem collection-like objects (e.g., file system directories) within a
directories) within a server's namespace. server's namespace.
All DAV compliant resources MUST support the HTTP URL namespace All DAV compliant resources MUST support the HTTP URL namespace
model specified herein. model specified herein.
3.1 Collection Resources 4.1 Collection Resources
A collection is a resource whose state consists of an unordered list A collection is a resource whose state consists of an unordered list
of internal members, an unordered list of external members, and a of internal members and a set of properties. An internal member
set of properties. An internal member resource MUST have a URI that resource MUST have a URI that is immediately relative to the base
is immediately relative to the base URI of the collection. That is, URI of the collection. That is, the internal member's URI is equal
the internal member's URI is equal to the parent collection's URI to the parent collection's URI plus an additional segment where
plus an additional segment where segment is defined in Section 3.2.1 segment is defined in section 3.2.1 of RFC 2068 [Fielding et al.,
of RFC 2068 [Fielding et al., 1996]. 1996].
An external member resource is a resource that could not be an Any given internal member MUST only belong to the collection once,
internal member resource. Any given internal or external Member MUST i.e., it is illegal to have multiple instances of the same URI in a
only belong to the collection once, i.e., it is illegal to have collection. Properties defined on collections behave exactly as do
multiple instances of the same URI in a collection. Properties properties on non-collection resources.
defined on collections behave exactly as do properties on non-
collection resources. WebDAV servers MUST treat HTTP URL namespaces as collections,
regardless of whether they were created with the MKCOL method
described in section 7.3.
There is a standing convention that when a collection is referred to There is a standing convention that when a collection is referred to
by its name without a trailing slash, the trailing slash is by its name without a trailing slash, the trailing slash is
automatically appended. Due to this, a resource MAY accept a URI automatically appended. Due to this, a resource may accept a URI
without a trailing "/" to point to a collection. In this case it without a trailing "/" to point to a collection. In this case it
SHOULD return a location header in the response pointing to the URL SHOULD return a location header in the response pointing to the URL
ending with the "/". For example, if a client invokes a method on ending with the "/". For example, if a client invokes a method on
http://foo.bar/blah (no trailing slash), the resource http://foo.bar/blah (no trailing slash), the resource
http://foo.bar/blah/ (trailing slash) MAY respond as if the http://foo.bar/blah/ (trailing slash) may respond as if the
operation were invoked on it, and SHOULD return a location header operation were invoked on it, and should return a location header
with http://foo.bar/blah/ in it. In general clients SHOULD use the with http://foo.bar/blah/ in it. In general clients SHOULD use the
"/" form of collection names. "/" form of collection names.
3.2 Creation and Retrieval of Collection Resources 4.2 Creation and Retrieval of Collection Resources
This document specifies the MKCOL method to create new collection This document specifies the MKCOL method to create new collection
resources, rather than using the existing HTTP/1.1 PUT or POST resources, rather than using the existing HTTP/1.1 PUT or POST
method, for the following reasons method, for the following reasons:
In HTTP/1.1, the PUT method is defined to store the request body at In HTTP/1.1, the PUT method is defined to store the request body at
the location specified by the Request-URI. While a description the location specified by the Request-URI. While a description
format for a collection can readily be constructed for use with PUT, format for a collection can readily be constructed for use with PUT,
the implications of sending such a description to the server are the implications of sending such a description to the server are
undesirable. For example, if a description of a collection that undesirable. For example, if a description of a collection that
omitted some existing resources were PUT to a server, this might be omitted some existing resources were PUT to a server, this might be
interpreted as a command to remove those members. This would extend interpreted as a command to remove those members. This would extend
PUT to perform DELETE functionality, which is undesirable since it PUT to perform DELETE functionality, which is undesirable since it
changes the semantics of PUT, and makes it difficult to control changes the semantics of PUT, and makes it difficult to control
DELETE functionality with an access control scheme based on methods. DELETE functionality with an access control scheme based on methods.
While the POST method is sufficiently open-ended that a "create a While the POST method is sufficiently open-ended that a "create a
collection" POST command could be constructed, this is undesirable collection" POST command could be constructed, this is undesirable
because it would be difficult to separate access control for because it would be difficult to separate access control for
collection creation from other uses of POST. collection creation from other uses of POST.
The exact definition of the behavior of GET and PUT on collections The exact definition of the behavior of GET and PUT on collections
is defined later in this document. is defined later in this document.
3.3 HTTP URL Namespace Model 4.3 HTTP URL Namespace Model
The HTTP URL Namespace is a hierarchical namespace where the The HTTP URL Namespace is a hierarchical namespace where the
hierarchy is delimited with the "/" character. DAV compliant hierarchy is delimited with the "/" character. DAV compliant
resources MUST maintain the consistency of the HTTP URL namespace. resources MUST maintain the consistency of the HTTP URL namespace.
Any attempt to create a resource (excepting the root member of a For example, if the collection http://www.foo.bar.org/a/ exists, but
namespace) that would not be the internal member of a collection http://www.foo.bar.org/a/b/ does not exist, an attempt to create
MUST fail. For example, if the collection http://www.foo.bar.org/a/ http://www.foo.bar.org/a/b/c must fail.
exists, but http://www.foo.bar.org/a/b/does not exist, an attempt to
create http://www.foo.bar.org/a/b/c must fail.
3.4 Source Resources and Output Resources 4.4 Source Resources and Output Resources
For many resources, the entity returned by a GET method exactly For many resources, the entity returned by a GET method exactly
matches the persistent state of the resource, for example, a GIF matches the persistent state of the resource, for example, a GIF
file stored on a disk. For this simple case, the URL at which a file stored on a disk. For this simple case, the URL at which a
resource is accessed is identical to the URL at which the source resource is accessed is identical to the URL at which the source
(the persistent state) of the resource is accessed. This is also (the persistent state) of the resource is accessed. This is also
the case for HTML source files that are not processed by the server the case for HTML source files that are not processed by the server
prior to transmission. prior to transmission.
However, the server can sometimes process HTML resources before they However, the server can sometimes process HTML resources before they
are transmitted as a return entity body. For example, server-side- are transmitted as a return entity body. For example, a server-
include directives within an HTML file instruct a server to replace side-include directive within an HTML file might instruct a server
the directive with another value, such as the current date. In this to replace the directive with another value, such as the current
case, what is returned by GET (HTML plus date) differs from the date. In this case, what is returned by GET (HTML plus date)
persistent state of the resource (HTML plus directive). Typically differs from the persistent state of the resource (HTML plus
there is no way to access the HTML resource containing the directive). Typically there is no way to access the HTML resource
unprocessed directive. containing the unprocessed directive.
Sometimes the entity returned by GET is the output of a data- Sometimes the entity returned by GET is the output of a data-
producing process that is described by one or more source resources producing process that is described by one or more source resources
(that may not even have a location in the URL namespace). A single (that may not even have a location in the URL namespace). A single
data-producing process may dynamically generate the state of a data-producing process may dynamically generate the state of a
potentially large number of output resources. An example of this is potentially large number of output resources. An example of this is
a CGI script that describes a "finger" gateway process that maps a CGI script that describes a "finger" gateway process that maps
part of the namespace of a server into finger requests, such as part of the namespace of a server into finger requests, such as
http://www.foo.bar.org/finger_gateway/user@host. http://www.foo.bar.org/finger_gateway/user@host.
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source resource(s) is desired, the source resource(s) should be source resource(s) is desired, the source resource(s) should be
given a location in the URI namespace. This source location should given a location in the URI namespace. This source location should
not be one of the locations at which the generated output is not be one of the locations at which the generated output is
retrievable, since in general it is impossible for the server to retrievable, since in general it is impossible for the server to
differentiate requests for source resources from requests for differentiate requests for source resources from requests for
process output resources. There is often a many-to-many process output resources. There is often a many-to-many
relationship between source resources and output resources. relationship between source resources and output resources.
On WebDAV compliant servers, for all output resources which have a On WebDAV compliant servers, for all output resources which have a
single source resource (and that source resource has a URI), the URI single source resource (and that source resource has a URI), the URI
of the source resource SHOULD be stored in a link on the output of the source resource may be stored in a link on the output
resource with type http://www.iana.org/standards/dav/source (see resource with type DAV:source (see section 12.10 for a description
Section 12.11 for a description of the source link). Note that by of the source link property). Storing the source URIs in links on
storing the source URIs in links on the output resources, the burden the output resources places the burden of discovering the source on
of discovering the source is placed on the authoring client. the authoring client. Note that the value of a source link is not
guaranteed to point to the correct source. Source links may break
or incorrect values may be entered. Also note that not all servers
will allow the client to set the source link value. For example a
server which generates source links on the fly for its CGI files
will most likely not allow a client to set the source link value.
4 Locking 5 Locking
The ability to lock a resource provides a mechanism for serializing The ability to lock a resource provides a mechanism for serializing
access to that resource. Using a lock, an authoring client can access to that resource. Using a lock, an authoring client can
provide a reasonable guarantee that another principal will not provide a reasonable guarantee that another principal will not
modify a resource while it is being edited. In this way, a client modify a resource while it is being edited. In this way, a client
can prevent the "lost update" problem. can prevent the "lost update" problem.
This specification allows locks to vary over two client-specified This specification allows locks to vary over two client-specified
parameters, the number of principals involved (exclusive vs. shared) parameters, the number of principals involved (exclusive vs. shared)
and the type of access to be granted. This document defines locking and the type of access to be granted. This document defines locking
for only one access type, write. However, the syntax is extensible, for only one access type, write. However, the syntax is extensible,
and permits the eventual specification of locking for other access and permits the eventual specification of locking for other access
types. types.
4.1 Exclusive Vs. Shared Locks 5.1 Exclusive Vs. Shared Locks
The most basic form of lock is an exclusive lock. This is a lock The most basic form of lock is an exclusive lock. This is a lock
where the access right in question is only granted to a single where the access right in question is only granted to a single
principal. The need for this arbitration results from a desire to principal. The need for this arbitration results from a desire to
avoid having to constantly merge results. avoid having to merge results.
However, there are times when the goal of a lock is not to exclude However, there are times when the goal of a lock is not to exclude
others from exercising an access right but rather to provide a others from exercising an access right but rather to provide a
mechanism for principals to indicate that they intend to exercise mechanism for principals to indicate that they intend to exercise
their access right. Shared locks are provided for this case. A their access rights. Shared locks are provided for this case. A
shared lock allows multiple principals to receive a lock. Hence any shared lock allows multiple principals to receive a lock. Hence any
principal with appropriate access can get the lock. principal with appropriate access can get the lock.
With shared locks there are two trust sets that affect a resource. With shared locks there are two trust sets that affect a resource.
The first trust set is created by access permissions. Principals The first trust set is created by access permissions. Principals
who are trusted, for example, may have permission to write the who are trusted, for example, may have permission to write to the
resource. Those who are not, don't. Among those who have access resource. Among those who have access permission to write to the
permission to write the resource, the set of principals who have resource, the set of principals who have taken out a shared lock
taken out a shared lock also must trust each other, creating a also must trust each other, creating a (typically) smaller trust set
(typically) smaller trust set within the access permission write within the access permission write set.
set.
Starting with every possible principal on the Internet, in most Starting with every possible principal on the Internet, in most
situations the vast majority of these principals will not have write situations the vast majority of these principals will not have write
access to a given resource. Of the small number who do have write access to a given resource. Of the small number who do have write
access, some principals may decide to guarantee their edits are free access, some principals may decide to guarantee their edits are free
from overwrite conflicts by using exclusive write locks. Others may from overwrite conflicts by using exclusive write locks. Others may
decide they trust their collaborators will not overwrite their work decide they trust their collaborators will not overwrite their work
(the potential set of collaborators being the set of principals who (the potential set of collaborators being the set of principals who
have write permission) and use a shared lock, which informs their have write permission) and use a shared lock, which informs their
collaborators that a principal may be working on the resource. collaborators that a principal may be working on the resource.
The WebDAV extensions to HTTP do not need to provide all of the The WebDAV extensions to HTTP do not need to provide all of the
communications paths necessary for principals to coordinate their communications paths necessary for principals to coordinate their
activities. When using shared locks, principals may use any out of activities. When using shared locks, principals may use any out of
band communication channel to coordinate their work (e.g., face-to- band communication channel to coordinate their work (e.g., face-to-
face interaction, written notes, post-it notes on the screen, face interaction, written notes, post-it notes on the screen,
telephone conversation, Email, etc.) The intent of a shared lock is telephone conversation, Email, etc.) The intent of a shared lock is
to let collaborators know who else may be working on a resource. to let collaborators know who else may be working on a resource.
Shared locks are included because experience from web distributed Shared locks are included because experience from web distributed
authoring systems has indicated that exclusive write locks are often authoring systems has indicated that exclusive locks are often too
too rigid. An exclusive write lock is used to enforce a particular rigid. An exclusive lock is used to enforce a particular editing
editing process: take out exclusive write lock, read the resource, process: take out an exclusive lock, read the resource, perform
perform edits, write the resource, release the lock. This editing edits, write the resource, release the lock. This editing process
process has the problem that locks are not always properly released, has the problem that locks are not always properly released, for
for example when a program crashes, or when a lock owner leaves example when a program crashes, or when a lock owner leaves without
without unlocking a resource. While both timeouts and unlocking a resource. While both timeouts and administrative action
administrative action can be used to remove an offending lock, can be used to remove an offending lock, neither mechanism may be
neither mechanism may be available when needed; the timeout may be available when needed; the timeout may be long or the administrator
long or the administrator may not be available. may not be available.
Despite their potential problems, exclusive write locks are
extremely useful, since often a guarantee of freedom from overwrite
conflicts is what is needed. This specification provides both
exclusive write locks and the less strict mechanism of shared locks.
4.2 Required Support 5.2 Required Support
A WebDAV compliant server is not required to support locking in any A WebDAV compliant server is not required to support locking in any
form. If the server does support locking it MAY choose to support form. If the server does support locking it may choose to support
any combination of exclusive and shared locks for any access types. any combination of exclusive and shared locks for any access types.
The reason for this flexibility is that locking policy strikes to The reason for this flexibility is that locking policy strikes to
the very heart of the resource management and versioning systems the very heart of the resource management and versioning systems
employed by various storage repositories. These repositories employed by various storage repositories. These repositories
require control over what sort of locking will be made available. require control over what sort of locking will be made available.
For example, some repositories only support shared write locks while For example, some repositories only support shared write locks while
others only provide support for exclusive write locks while yet others only provide support for exclusive write locks while yet
others use no locking at all. As each system is sufficiently others use no locking at all. As each system is sufficiently
different to merit exclusion of certain locking features, this different to merit exclusion of certain locking features, this
specification leaves locking as the sole axis of negotiation within specification leaves locking as the sole axis of negotiation within
WebDAV. WebDAV.
4.3 Lock Tokens 5.3 Lock Tokens
A lock token is a URI that identifies a particular lock. A lock A lock token is a type of state token, represented as a URI, which
token is returned by every successful LOCK operation in the Lock- identifies a particular lock. A lock token is returned by every
Token response header, and can also be discovered through lock successful LOCK operation in the Lock-Token response header, and can
discovery on a resource. also be discovered through lock discovery on a resource.
Lock token URIs are required to be unique across all resources for Lock token URIs MUST be unique across all resources for all time.
all time. This uniqueness constraint allows lock tokens to be This uniqueness constraint allows lock tokens to be submitted across
submitted across resources and servers without fear of confusion. resources and servers without fear of confusion.
This specification provides a lock token URI scheme called This specification provides a lock token URI scheme called
opaquelocktoken that meets the uniqueness requirements. However opaquelocktoken that meets the uniqueness requirements. However
resources are free to return any URI scheme so long as it meets the resources are free to return any URI scheme so long as it meets the
uniqueness requirements. uniqueness requirements.
4.4 opaquelocktoken Lock Token URI Scheme Having a lock token provides no special access rights. Anyone can
find out anyone else's lock token by performing lock discovery.
Locks MUST be enforced based upon whatever authentication mechanism
is used by the server, not based on the secrecy of the token values.
5.4 opaquelocktoken Lock Token URI Scheme
The opaquelocktoken URI scheme is designed to be unique across all The opaquelocktoken URI scheme is designed to be unique across all
resources for all time. Due to this uniqueness quality, a client resources for all time. Due to this uniqueness quality, a client
MAY submit an opaque lock token in a Lock-Token request header and may submit an opaque lock token in an If header on a resource other
an If-[None]-State-Match header on a resource other than the one than the one that returned it.
that returned it.
All resources MUST recognize the opaquelocktoken scheme and, at All resources MUST recognize the opaquelocktoken scheme and, at
minimum, recognize that the lock token was not generated by the minimum, recognize that the lock token does not refer to an
resource. Note, however, that resources are not required to outstanding lock on the resource.
generate opaquelocktokens in LOCK method responses.
In order to guarantee uniqueness across all resources for all time In order to guarantee uniqueness across all resources for all time
the opaquelocktoken requires the use of the Universally Unique the opaquelocktoken requires the use of the Universally Unique
Identifier (UUID, also known as a Globally Unique Identifier, or Identifier (UUID, also known as a Globally Unique Identifier, or
GUID) mechanism, as described in [Leach, Salz, 1998]. GUID) mechanism, as described in [Leach, Salz, 1998].
Opaquelocktoken generators, however, have a choice of how they Opaquelocktoken generators, however, have a choice of how they
create these tokens. They can either generate a new UUID for every create these tokens. They can either generate a new UUID for every
lock token they create, which is potentially very expensive, or they lock token they create or they can create a single UUID and then add
can create a single UUID and then add extension characters. If the extension characters. If the second method is selected then the
second method is selected then the program generating the extensions program generating the extensions MUST guarantee that the same
MUST guarantee that the same extension will never be used twice with extension will never be used twice with the associated UUID.
the associated UUID.
OpaqueLockToken-URI = "opaquelocktoken:" UUID [Extension] ; The OpaqueLockToken-URI = "opaquelocktoken:" UUID [Extension] ; The
UUID production is the string form of a UUID, as defined in [Leach, UUID production is the string form of a UUID, as defined in [Leach,
Salz, 1998]. Note that white space (LWS) is not allowed between Salz, 1998]. Note that white space (LWS) is not allowed between
elements of this production. elements of this production.
Extension = path ; path is defined in Section 3.2.1 of RFC 2068 Extension = path ; path is defined in section 3.2.1 of RFC 2068
[Fielding et al., 1996] [Fielding et al., 1996]
4.5 Lock Capability Discovery 5.5 Lock Capability Discovery
Since server lock support is optional, a client trying to lock a Since server lock support is optional, a client trying to lock a
resource on a server can either try the lock and hope for the best, resource on a server can either try the lock and hope for the best,
or perform some form of discovery to determine what lock or perform some form of discovery to determine what lock
capabilities the server supports. This is known as lock capability capabilities the server supports. This is known as lock capability
discovery. Lock capability discovery differs from discovery of discovery. Lock capability discovery differs from discovery of
supported access control types, since there may be access control supported access control types, since there may be access control
types without corresponding lock types. A client can determine what types without corresponding lock types. A client can determine what
lock types the server supports by retrieving the supportedlock lock types the server supports by retrieving the supportedlock
property. property.
Any DAV compliant resource that supports the LOCK method MUST Any DAV compliant resource that supports the LOCK method MUST
support the supportedlock property. support the supportedlock property.
4.6 Active Lock Discovery 5.6 Active Lock Discovery
If another principal locks a resource that a principal wishes to If another principal locks a resource that a principal wishes to
access, it is useful for the second principal to be able to find out access, it is useful for the second principal to be able to find out
who the first principal is. For this purpose the lockdiscovery who the first principal is. For this purpose the lockdiscovery
property is provided. This property lists all outstanding locks, property is provided. This property lists all outstanding locks,
describes their type, and provides their lock token. describes their type, and where available, provides their lock
token.
Any DAV compliant resource that supports the LOCK method MUST Any DAV compliant resource that supports the LOCK method MUST
support the lockdiscovery property. support the lockdiscovery property.
5 Write Lock 5.7 Usage Considerations
This section describes the semantics specific to the write access Although the locking mechanisms specified here provide some help in
type for locks. The write lock is a specific instance of a lock preventing lost updates, they cannot guarantee that updates will
type, and is the only lock type described in this specification. A never be lost. Consider the following scenario:
DAV compliant resource MAY support the write lock.
5.1 Methods Restricted by Write Locks Two clients A and B are interested in editing the resource
'index.html'. Client A is an HTTP client rather than a WebDAV
client, and so does not know how to perform locking.
A write lock prevents a principal without the lock from successfully Client A doesn't lock the document, but does a GET and begins
executing a PUT, POST, PROPPATCH, LOCK, UNLOCK, MOVE, DELETE, MKCOL, editing.
ADDREF or DELREF on the locked resource. All other current methods, Client B does LOCK, performs a GET and begins editing.
Client B finishes editing, performs a PUT, then an UNLOCK.
Client A performs a PUT, overwriting and losing all of B's changes.
There are several reasons why the WebDAV protocol itself cannot
prevent this situation. First, it cannot force all clients to use
locking because it must be compatible with HTTP clients that do not
comprehend locking. Second, it cannot require servers to support
locking because of the variety of repository implementations, some
of which rely on reservations and merging rather than on locking.
Finally, being stateless, it cannot enforce a sequence of operations
like LOCK / GET / PUT / UNLOCK.
WebDAV servers that support locking can reduce the likelihood that
clients will accidentally overwrite each other's changes by
requiring clients to lock resources before modifying them. Such
servers would effectively prevent HTTP 1.0 and HTTP 1.1 clients from
modifying resources.
WebDAV clients can be good citizens by using a lock / retrieve /
write /unlock sequence of operations (at least by default) whenever
they interact with a WebDAV server that supports locking.
HTTP 1.1 clients can be good citizens, avoiding overwriting other
clients' changes, by using entity tags in If-Match headers with any
requests that would modify resources.
Information managers may attempt to prevent overwrites by
implementing client-side procedures requiring locking before
modifying WebDAV resources.
6 Write Lock
This section describes the semantics specific to the write lock
type. The write lock is a specific instance of a lock type, and is
the only lock type described in this specification.
6.1 Methods Restricted by Write Locks
A write lock MUST prevent a principal without the lock from
successfully executing a PUT, POST, PROPPATCH, LOCK, UNLOCK, MOVE,
DELETE, or MKCOL on the locked resource. All other current methods,
GET in particular, function independent of the lock. GET in particular, function independent of the lock.
Note, however, that as new methods are created it will be necessary Note, however, that as new methods are created it will be necessary
to specify how they interact with a write lock. to specify how they interact with a write lock.
5.2 Write Locks and Properties 6.2 Write Locks and Properties
While those without a write lock may not alter a property on a While those without a write lock may not alter a property on a
resource it is still possible for the values of live properties to resource it is still possible for the values of live properties to
change, even while locked, due to the requirements of their schemas. change, even while locked, due to the requirements of their schemas.
Only dead properties and live properties defined to respect locks Only dead properties and live properties defined to respect locks
are guaranteed not to change while write locked. are guaranteed not to change while write locked.
5.3 Write Locks and Null Resources 6.3 Write Locks and Null Resources
It is possible to assert a write lock on a null resource in order to It is possible to assert a write lock on a null resource in order to
lock the name. A write locked null resource acts in all ways as a lock the name. A write locked null resource acts in all ways as a
null resource other than it MUST respond to a PROPFIND request and null resource, except that it MUST respond to a PROPFIND request and
MUST support the lockdiscovery and supportedlock properties. MUST support the lockdiscovery and supportedlock properties.
Until a method such as PUT or MKCOL is executed, the resource stays Until a method such as PUT or MKCOL is executed, the resource MUST
in the null state with the exception of the behavior stated above. stay in the null state with the exception of the behavior described
above.
If the resource is unlocked without a PUT, MKCOL, or similar method If the resource is unlocked without a PUT, MKCOL, or similar method
having been executed, the resource is no longer required to support having been executed then the resource MUST return to its original
the PROPFIND method or the lockdiscovery and supportedlock NULL state.
properties.
5.4 Write Locks and Collections A return to a full NULL state is generally interpreted as meaning
that any attempt to execute a method on the resource will result in
a 404 Not Found.
6.4 Write Locks and Collections
A write lock on a collection prevents the addition or removal of A write lock on a collection prevents the addition or removal of
members of the collection by non-lock owners. As a consequence, members of the collection by non-lock owners. As a consequence,
when a principal issues a request to create a new internal member of when a principal issues a request to create a new internal member of
a write locked collection using PUT or POST, or to remove an a write locked collection using PUT or POST, or to remove an
existing internal member of a write locked collection using DELETE, existing internal member of a write locked collection using DELETE,
this request MUST fail if the principal does not have a write lock this request MUST fail if the principal does not have a write lock
on the collection. on the collection.
However, if a write lock request is issued to a collection However, if a write lock request is issued to a collection
containing internal member resources that are currently locked in a containing internal member resources that are currently locked in a
manner which conflicts with the write lock, the request MUST fail manner which conflicts with the write lock, the request MUST fail
with a 425 Locked status code. with a 423 Locked status code.
If a lock owner causes a resource to be added as an internal member If a lock owner causes a resource to be added as an internal member
of a locked collection then the new resource is automatically added of a locked collection then the new resource MUST be automatically
to the lock. This is the only mechanism that allows a resource to added to the lock. This is the only mechanism that allows a
resource to be added to a write lock. Thus, for example, if the
be added to a write lock. Thus, for example, if the collection collection /a/b/ is write locked and the resource /c is moved to
/a/b/ is write locked and the resource /c is moved to /a/b/c then /a/b/c then /a/b/c will be added to the write lock.
/a/b/c will be added to the write lock.
5.5 Write Locks and COPY/MOVE
A COPY method invocation MUST NOT duplicate any write locks active
on the source. However, as previously noted, if the COPY copies the
resource into a collection that is depth locked then the resource
will be added to the lock.
A MOVE does not move the write lock with the resource. There are two
exceptions to this rule. First, as noted in section 5.4, if the MOVE
makes the resource a child of a collection that is depth locked then
the resource will be under the same lock. Second, if a depth locked
resource is moved to a destination that is within the scope of the
same depth lock (e.g., within the namespace tree covered by the
lock), the moved resource is still a member of the lock. In both
cases a Lock-Token header MUST be submitted containing a lock token
for the lock on the source, if locked, and on the destination.
5.6 Refreshing Write Locks
A client MUST NOT submit the same write lock request twice. Note
that a client is always aware it is resubmitting the same lock
request because it must include the Lock-Token header in order to
make the request for a resource that is already locked.
However, a client MAY submit a LOCK method with a Lock-Token header
but without a body. This form of LOCK MAY only be used to "refresh"
a lock. Currently, refreshing a lock only means that any timers
associated with the lock are re-set.
A server MAY return a Timeout header with a lock refresh that is
different than the Timeout header returned when the lock was
originally requested. Additionally clients MAY submit Timeout
headers of arbitrary value with their lock refresh requests.
Servers, as always, MAY ignore Timeout headers submitted by the
client.
If an error is received in response to a refresh LOCK request the
client MUST assume that the lock was not refreshed.
5.7 Write Locks and The Lock-Token Request Header 6.5 Write Locks and the If Request Header
If a user agent is not required to have knowledge about a lock when If a user agent is not required to have knowledge about a lock when
requesting an operation on a locked resource, the following scenario requesting an operation on a locked resource, the following scenario
might occur. Program A, run by User A, takes out a write lock on a might occur. Program A, run by User A, takes out a write lock on a
resource. Program B, also run by User A, has no knowledge of the resource. Program B, also run by User A, has no knowledge of the
lock taken out by Program A, yet performs a PUT to the locked lock taken out by Program A, yet performs a PUT to the locked
resource. In this scenario, the PUT succeeds because locks are resource. In this scenario, the PUT succeeds because locks are
associated with a principal, not a program, and thus program B, associated with a principal, not a program, and thus program B,
because it is acting with principal A's credential, is allowed to because it is acting with principal A's credential, is allowed to
perform the PUT. However, had program B known about the lock, it perform the PUT. However, had program B known about the lock, it
would not have overwritten the resource, preferring instead to would not have overwritten the resource, preferring instead to
present a dialog box describing the conflict to the user. Due to present a dialog box describing the conflict to the user. Due to
this scenario, a mechanism is needed to prevent different programs this scenario, a mechanism is needed to prevent different programs
from accidentally ignoring locks taken out by other programs with from accidentally ignoring locks taken out by other programs with
the same authorization. the same authorization.
In order to prevent these collisions the Lock-Token request header, In order to prevent these collisions a lock token MUST be submitted
defined in Section 8.7, is introduced. by an authorized principal in the If header for all locked resources
that a method may interact with or the method MUST fail. For
example, if a resource is to be moved and both the source and
destination are locked then two lock tokens must be submitted, one
for the source and the other for the destination.
5.7.1 Write Lock Token Example 6.5.1 Write Lock Example
>>Request >>Request
COPY /~fielding/index.html HTTP/1.1 COPY /~fielding/index.html HTTP/1.1
Host: www.ics.uci.edu Host: www.ics.uci.edu
Destination: http://www.ics.uci.edu/users/f/fielding/index.html Destination: http://www.ics.uci.edu/users/f/fielding/index.html
Lock-Token: <opaquelocktoken:f81d4fae-7dec-11d0-a765-00a0c91e6bf6> If: <http://www.ics.uci.edu/users/f/fielding/index.html>
Authorization: Digest username="fielding", (<opaquelocktoken:f81d4fae-7dec-11d0-a765-00a0c91e6bf6>)
realm="fielding@ics.uci.edu", nonce="...",
uri="/~fielding/index.html", response="...",
opaque="..."
>>Response >>Response
HTTP/1.1 204 No Content HTTP/1.1 204 No Content
In this example, even though both the source and destination are In this example, even though both the source and destination are
locked, only one lock token must be submitted, for the lock on the locked, only one lock token must be submitted, for the lock on the
destination. This is due to the source resource not being modified destination. This is because the source resource is not modified by
during a COPY, and hence unaffected by the write lock. The a COPY, and hence unaffected by the write lock. In this example,
Authorization header provides the Digest authentication credentials user agent authentication has previously occurred via a mechanism
for the principal making the request (note that the nonce, response, outside the scope of the HTTP protocol, in the underlying transport
and opaque fields have not been calculated for this example). The layer.
source and the destination resources are both located within the
same authentication realm, therefore only one set of Authorization
credentials needs to be submitted.
6 Notational Conventions 6.6 Write Locks and COPY/MOVE
Since this document describes a set of extensions to the HTTP/1.1 A COPY method invocation MUST NOT duplicate any write locks active
protocol, the augmented BNF used herein to describe protocol on the source. However, as previously noted, if the COPY copies the
elements is exactly the same as described in Section 2.1 of resource into a collection that is depth locked then the resource
[Fielding et al., 1997]. Since this augmented BNF uses the basic will be added to the lock.
production rules provided in Section 2.2 of [Fielding et al., 1997],
these rules apply to this document as well.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", A MOVE MUST NOT move the write lock with the resource although the
"SHOULD", SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this resource is subject to being added to an existing lock as specified
document are to be interpreted as described in RFC 2119 [Bradner, in section 6.4. For example, if the MOVE makes the resource a child
1997]. of a collection that is depth locked then the resource will be under
that collection's lock. Additionally, if a depth locked resource is
moved to a destination that is within the scope of the same depth
lock (e.g., within the namespace tree covered by the lock), the
moved resource will again be a member of the lock. In both these
examples, as specified in section 6.5, an If header must be
submitted containing a lock token for both the source and
destination.
6.7 Refreshing Write Locks
A client MUST NOT submit the same write lock request twice. Note
that a client is always aware it is resubmitting the same lock
request because it must include the lock token in the If header in
order to make the request for a resource that is already locked.
However, a client may submit a LOCK method with an If header but
without a body. This form of LOCK MUST only be used to "refresh" a
lock. Meaning, at minimum, that any timers associated with the lock
MUST be re-set.
A server may return a Timeout header with a lock refresh that is
different than the Timeout header returned when the lock was
originally requested. Additionally clients may submit Timeout
headers of arbitrary value with their lock refresh requests.
Servers, as always, may ignore Timeout headers submitted by the
client.
If an error is received in response to a refresh LOCK request the
client SHOULD assume that the lock was not refreshed.
7 HTTP Methods for Distributed Authoring 7 HTTP Methods for Distributed Authoring
The following new HTTP methods use XML as a request and response
format. All DAV compliant clients and resources MUST use XML
parsers that are compliant with [Bray, Paoli, Sperberg-McQueen,
1998]. All XML used in either requests or responses MUST be, at
minimum, well formed. If a server receives ill-formed XML in a
request it MUST reject the entire request with a 400 Bad Request.
If a client receives ill-formed XML in a response then it MUST NOT
assume anything about the outcome of the executed method and SHOULD
treat the server as malfunctioning.
7.1 PROPFIND 7.1 PROPFIND
The PROPFIND method retrieves properties defined on the Request-URI, The PROPFIND method retrieves properties defined on the Request-URI,
if the resource does not have any internal members, or on the if the resource does not have any internal members, or on the
Request-URI and potentially its member resources, if the resource Request-URI and potentially its member resources, if the resource
does have internal members. All DAV compliant resources MUST does have internal members. All DAV compliant resources MUST
support the PROPFIND method. support the PROPFIND method and the propfind XML element (section
11.14) along with all XML elements defined for use with that
element.
A client MAY submit a Depth header with a value of "0", "1", or A client may submit a Depth header with a value of "0", "1", or
"infinity" with a PROPFIND on a resource with internal members. DAV "infinity" with a PROPFIND on a resource with internal members. DAV
compliant servers MUST support the "0", "1" and "infinity" compliant servers MUST support the "0", "1" and "infinity"
behaviors. By default, the PROPFIND method without a Depth header behaviors. By default, the PROPFIND method without a Depth header
MUST act as if a "Depth: infinity" header was included. MUST act as if a "Depth: infinity" header was included.
A client MAY submit a propfind XML element in the body of the A client may submit a propfind XML element in the body of the
request method describing what information is being requested. It request method describing what information is being requested. It
is possible to request particular property values, all property is possible to request particular property values, all property
values, or a list of the names of the resource's properties. A values, or a list of the names of the resource's properties. A
client MAY choose not to submit a request body. An empty request client may choose not to submit a request body. An empty PROPFIND
body MUST be treated as a request for the names and values of all request body MUST be treated as a request for the names and values
properties. of all properties.
The response is a text/xml message body that contains a multistatus All servers MUST support returning a response of content type
XML element that describes the results of the attempts to retrieve text/xml that contains a multistatus XML element that describes the
the various properties. If a property was successfully retrieved results of the attempts to retrieve the various properties.
then its value MUST be returned in a prop XML element.
If there is an error retrieving a property then a proper error If there is an error retrieving a property then a proper error
result must be included. Requests to retrieve the value of a result MUST be included in the response. A request to retrieve the
property which does not exist is an error and MUST be noted with a value of a property which does not exist is an error and MUST be
noted, if the response uses a multistatus XML element, with a
response XML element which contains a 404 Not Found status value. response XML element which contains a 404 Not Found status value.
Consequently, the multistatus XML element for a resource with Consequently, the multistatus XML element for a resource with
members MUST include a response XML element for each member of the members MUST include a response XML element for each member of the
resource, to whatever depth was requested. Each response XML element resource, to whatever depth was requested. Each response XML element
MUST contain an href XML element that identifies the resource on MUST contain an href XML element that identifies the resource on
which the properties in the prop XML element are defined. Results which the properties in the prop XML element are defined. Results
for a PROPFIND on a resource with internal members are returned as a for a PROPFIND on a resource with internal members are returned as a
flat list whose order of entries is not significant. flat list whose order of entries is not significant.
In the case of allprop and propname, if a principal does not have In the case of allprop and propname, if a principal does not have
the right to know if a particular property exists then a 404 Not the right to know whether a particular property exists then the
Found MUST be returned. property should be silently excluded from the response.
The results of this method SHOULD NOT be cached. The results of this method SHOULD NOT be cached.
7.1.1 Example: Retrieving Named Properties 7.1.1 Example: Retrieving Named Properties
>>Request >>Request
PROPFIND /files/ HTTP/1.1 PROPFIND /files/ HTTP/1.1
Host: www.foo.bar Host: www.foo.bar
Depth: 0 Depth: 0
Content-type: text/xml Content-type: text/xml
Content-Length: xyz Content-Length: xyz
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href ="http://www.iana.org/standards/dav/" as="D"?> <?xml:namespace name="DAV:" as="D"?>
<?xml:namespace name="http://www.foo.bar/boxschema/" as="R"?>
<D:propfind> <D:propfind>
<D:href>http://www.foo.bar/boxschema/bigbox</D:href> <D:prop>
<D:href>http://www.foo.bar/boxschema/author</D:href> <R:bigbox/>
<D:href>http://www.foo.bar/boxschema/DingALing</D:href> <R:author/>
<D:href>http://www.foo.bar/boxschema/Random</D:href> <R:DingALing/>
<R:Random/>
</D:prop>
</D:propfind> </D:propfind>
>>Response >>Response
HTTP/1.1 207 Multi-Status HTTP/1.1 207 Multi-Status
Content-Type: text/xml Content-Type: text/xml
Content-Length: xxxxx Content-Length: xxxxx
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href ="http://www.iana.org/standards/dav/" as="D"?> <?xml:namespace name="DAV:" as="D"?>
<?namespace href="http://www.foo.bar/boxschema" as="R"?> <?xml:namespace name="http://www.foo.bar/boxschema/" as="R"?>
<D:multistatus> <D:multistatus>
<D:response> <D:response>
<D:href>http://www.foo.bar/files/</D:href> <D:href>http://www.foo.bar/files/</D:href>
<D:propstat> <D:propstat>
<D:prop> <D:prop>
<R:bigbox> <R:bigbox>
<R:BoxType>Box type A</R:BoxType> <R:BoxType>Box type A</R:BoxType>
</R:bigbox> </R:bigbox>
<R:author> <R:author>
<R:Name>J.J. Johnson</R:Name> <R:Name>J.J. Johnson</R:Name>
skipping to change at page 23, line 45 skipping to change at page 23, line 29
>>Request >>Request
PROPFIND /container/ HTTP/1.1 PROPFIND /container/ HTTP/1.1
Host: www.foo.bar Host: www.foo.bar
Depth: 1 Depth: 1
Content-Type: text/xml Content-Type: text/xml
Content-Length: xxxxx Content-Length: xxxxx
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href ="http://www.iana.org/standards/dav/" as="D"?> <?xml:namespace name="DAV:" as="D"?>
<D:propfind> <D:propfind>
<D:allprop/> <D:allprop/>
</D:propfind> </D:propfind>
>>Response >>Response
HTTP/1.1 207 Multi-Status HTTP/1.1 207 Multi-Status
Content-Type: text/xml Content-Type: text/xml
Content-Length: xxxxx Content-Length: xxxxx
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href="http://www.iana.org/standards/dav/" as="S"?> <?xml:namespace name="DAV:" as="D"?>
<?namespace href="http://www.foo.bar/boxschema/" as="R"?> <?xml:namespace name="http://www.foo.bar/boxschema/" as="R"?>
<S:multistatus> <D:multistatus>
<S:response> <D:response>
<S:href>http://www.foo.bar/container/</S:href> <D:href>http://www.foo.bar/container/</D:href>
<S:propstat> <D:propstat>
<S:prop> <D:prop>
<R:bigbox> <R:bigbox>
<R:BoxType>Box type A</R:BoxType> <R:BoxType>Box type A</R:BoxType>
</R:bigbox> </R:bigbox>
<R:author> <R:author>
<R:Name>Hadrian</R:Name> <R:Name>Hadrian</R:Name>
</R:author> </R:author>
<S:creationdate> <D:creationdate>
1997-12-01T17:42:21-08:00 1997-12-01T17:42:21-08:00
</S:creationdate> </D:creationdate>
<S:displayname> <D:displayname>
Example collection Example collection
</S:displayname> </D:displayname>
<S:externalmembers> <D:resourcetype><D:collection/></D:resourcetype>
<S:href>http://www.acme.com/front/</S:href> <D:supportedlock>
</S:externalmembers> <D:lockentry>
<S:resourcetype><S:collection/></S:resourcetype> <D:exclusive/><D:write/>
<S:supportedlock> </D:lockentry>
<S:lockentry> <D:lockentry>
<S:exclusive/><S:write/> <D:shared/><D:write/>
</S:lockentry> </D:lockentry>
<S:lockentry> </D:supportedlock>
<S:shared/><S:write/> </D:prop>
</S:lockentry> <D:status>HTTP/1.1 200 OK</D:status>
</S:supportedlock> </D:propstat>
</S:prop> </D:response>
<S:status>HTTP 1.1 200 OK</S:status> <D:response>
</S:propstat> <D:href>http://www.foo.bar/container/front.html</D:href>
</S:response> <D:propstat>
<S:response> <D:prop>
<S:href>http://www.foo.bar/container/front.html</S:href>
<S:propstat>
<S:prop>
<R:bigbox> <R:bigbox>
<R:BoxType>Box type B</R:BoxType> <R:BoxType>Box type B</R:BoxType>
</R:bigbox> </R:bigbox>
<S:creationdate> <D:creationdate>
1997-12-01T18:27:21-08:00 1997-12-01T18:27:21-08:00
</S:creationdate> </D:creationdate>
<S:displayname> <D:displayname>
Example HTML resource Example HTML resource
</S:displayname> </D:displayname>
<S:getcontentlength> <D:getcontentlength>
4525 4525
</S:getcontentlength> </D:getcontentlength>
<S:getcontenttype> <D:getcontenttype>
text/html text/html
</S:getcontenttype> </D:getcontenttype>
<S:getetag> <D:getetag>
zzyzx zzyzx
</S:getetag> </D:getetag>
<S:getlastmodified> <D:getlastmodified>
Monday, 12-Jan-98 09:25:56 GMT Monday, 12-Jan-98 09:25:56 GMT
</S:getlastmodified> </D:getlastmodified>
<S:resourcetype/> <D:resourcetype/>
<S:supportedlock> <D:supportedlock>
<S:lockentry> <D:lockentry>
<S:exclusive/><S:write/> <D:exclusive/><D:write/>
</S:lockentry> </D:lockentry>
<S:lockentry> <D:lockentry>
<S:shared/><S:write/> <D:shared/><D:write/>
</S:lockentry> </D:lockentry>
</S:supportedlock> </D:supportedlock>
</S:prop> </D:prop>
<S:status>HTTP 1.1 200 OK</S:status> <D:status>HTTP/1.1 200 OK</D:status>
</S:propstat> </D:propstat>
</S:response> </D:response>
</S:multistatus> </D:multistatus>
In this example, PROPFIND was invoked on the resource In this example, PROPFIND was invoked on the resource
http://www.foo.bar/container/ with a Depth header of 1, meaning the http://www.foo.bar/container/ with a Depth header of 1, meaning the
request applies to the resource and its children, and a propfind XML request applies to the resource and its children, and a propfind XML
element containing the allprop XML element, meaning the request element containing the allprop XML element, meaning the request
should return the name and value of all properties defined on each should return the name and value of all properties defined on each
resource. resource.
The resource http://www.foo.bar/container/ has seven properties The resource http://www.foo.bar/container/ has six properties
defined on it, named http://www.foo.bar/boxschema/bigbox, defined on it:
http://www.foo.bar/boxschema/author,
http://www.iana.org/standards/dav/creationdate, http://www.foo.bar/boxschema/bigbox,
http://www.iana.org/standards/dav/displayname, http://www.foo.bar/boxschema/author, DAV:creationdate,
http://www.iana.org/standards/dav/externalmembers, DAV:displayname, DAV:resourcetype, and DAV:supportedlock.
http://www.iana.org/standards/dav/resourcetype, and
http://www.iana.org/standards/dav/supportedlock. The last five The last four properties are WebDAV-specific, defined in section 12.
properties are WebDAV-specific, defined in Section 12. Since GET is Since GET is not supported on this resource, the get* properties
not supported on this resource, the get-* properties (e.g., get- (e.g., getcontentlength) are not defined on this resource. The DAV-
content-length) are not defined on this resource. The DAV-specific specific properties assert that "container" was created on December
properties assert that "container" was created on December 1, 1997, 1, 1997, at 5:42:21PM, in a time zone 8 hours west of GMT
at 5:42:21PM, in a time zone 8 hours west of GMT (creationdate), has (creationdate), has a name of "Example collection" (displayname), a
a name of "Example collection" (displayname), a single external
member resource, http://www.acme.com/front/ (externalmembers), a
collection resource type (resourcetype), and supports exclusive collection resource type (resourcetype), and supports exclusive
write and shared write locks (supportedlock). write and shared write locks (supportedlock).
The resource http://www.foo.bar/container/front.html has nine The resource http://www.foo.bar/container/front.html has nine
properties defined on it, named http://www.foo.bar/boxschema/bigbox properties defined on it:
(another instance of the "bigbox" property type),
http://www.iana.org/standards/dav/creationdate, http://www.foo.bar/boxschema/bigbox (another instance of the
http://www.iana.org/standards/dav/displayname, "bigbox" property type), DAV:creationdate, DAV:displayname,
http://www.iana.org/standards/dav/getcontentlength, DAV:getcontentlength, DAV:getcontenttype, DAV:getetag,
http://www.iana.org/standards/dav/getcontenttype, DAV:getlastmodified, DAV:resourcetype, and DAV:supportedlock.
http://www.iana.org/standards/dav/getetag,
http://www.iana.org/standards/dav/getlastmodified, The DAV-specific properties assert that "front.html" was created on
http://www.iana.org/standards/dav/resourcetype, and December 1, 1997, at 6:27:21PM, in a time zone 8 hours west of GMT
http://www.iana.org/standards/dav/supportedlock. The DAV-specific (creationdate), has a name of "Example HTML resource" (displayname),
properties assert that "front.html" was created on December 1, 1997, a content length of 4525 bytes (getcontentlength), a MIME type of
at 6:27:21PM, in a time zone 8 hours west of GMT (creationdate), has "text/html" (getcontenttype), an entity tag of "zzyzx" (getetag),
a name of "Example HTML resource" (displayname), a content length of was last modified on Monday, January 12, 1998, at 09:25:56 GMT
4525 (getcontentlength), a MIME type of "text/html"
(getcontenttype), an entity tag of "zzyzx" (getetag), was last
modified on Monday, January 12, 1998, at 09:25:56 GMT
(getlastmodified), has an undefined resource type, meaning that it (getlastmodified), has an undefined resource type, meaning that it
is not a collection (resourcetype), and supports both exclusive is not a collection (resourcetype), and supports both exclusive
write and shared write locks (supportedlock). write and shared write locks (supportedlock).
7.1.3 Example: Using propname to Retrieve all Property Names 7.1.3 Example: Using propname to Retrieve all Property Names
>>Request >>Request
PROPFIND /container/ HTTP/1.1 PROPFIND /container/ HTTP/1.1
Host: www.foo.bar Host: www.foo.bar
Content-Type: text/xml Content-Type: text/xml
Content-Length: xxxxx Content-Length: xxxxx
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href ="http://www.iana.org/standards/dav/" as="D"?> <?xml:namespace name="DAV:" as="D"?>
<D:propfind> <D:propfind>
<D:propname/> <D:propname/>
</D:propfind> </D:propfind>
>>Response >>Response
HTTP/1.1 207 Multi-Status HTTP/1.1 207 Multi-Status
Content-Type: text/xml Content-Type: text/xml
Content-Length: xxxx Content-Length: xxxx
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href="http://www.iana.org/standards/dav/" as="D"?> <?xml:namespace name="DAV:" as="D"?>
<?namespace href="http://www.foo.bar/boxschema/" as="R"?> <?xml:namespace name="http://www.foo.bar/boxschema/" as="R"?>
<D:multistatus> <D:multistatus>
<D:response> <D:response>
<D:href>http://www.foo.bar/container/</D:href> <D:href>http://www.foo.bar/container/</D:href>
<D:propstat> <D:propstat>
<D:prop> <D:prop>
<R:bigbox/> <R:bigbox/>
<R:author/> <R:author/>
<D:creationdate/> <D:creationdate/>
<D:displayname/> <D:displayname/>
<D:externalmembers/>
<D:resourcetype/> <D:resourcetype/>
<D:supportedlock/> <D:supportedlock/>
</D:prop> </D:prop>
<D:status>HTTP 1.1 200 OK</D:status> <D:status>HTTP/1.1 200 OK</D:status>
</D:propstat> </D:propstat>
</D:response> </D:response>
<D:response> <D:response>
<D:href>http://www.foo.bar/container/front.html</D:href> <D:href>http://www.foo.bar/container/front.html</D:href>
<D:propstat> <D:propstat>
<D:prop> <D:prop>
<R:bigbox/> <R:bigbox/>
<D:creationdate/> <D:creationdate/>
<D:displayname/> <D:displayname/>
<D:get-content-length/> <D:getcontentlength/>
<D:get-content-type/> <D:getcontenttype/>
<D:get-etag/> <D:getetag/>
<D:get-last-modified/> <D:getlastmodified/>
<D:resourcetype/> <D:resourcetype/>
<D:supportedlock/> <D:supportedlock/>
</D:prop> </D:prop>
<D:status>HTTP 1.1 200 OK</D:status> <D:status>HTTP/1.1 200 OK</D:status>
</D:propstat> </D:propstat>
</D:response> </D:response>
</D:multistatus> </D:multistatus>
In this example, PROPFIND is invoked on the collection resource In this example, PROPFIND is invoked on the collection resource
http://www.foo.bar/container/, with a propfind XML element http://www.foo.bar/container/, with a propfind XML element
containing the propname XML element, meaning the name of all containing the propname XML element, meaning the name of all
properties should be returned. Since no depth header is present, it properties should be returned. Since no depth header is present, it
assumes its default value of "infinity", meaning the name of the assumes its default value of "infinity", meaning the name of the
properties on the collection and all its progeny should be returned. properties on the collection and all its progeny should be returned.
Consistent with the previous example, resource Consistent with the previous example, resource
http://www.foo.bar/container/ has seven properties defined on it, http://www.foo.bar/container/ has six properties defined on it,
http://www.foo.bar/boxschema/bigbox, and
http://www.foo.bar/boxschema/author,
http://www.iana.org/standards/dav/creationdate,
http://www.iana.org/standards/dav/displayname,
http://www.iana.org/standards/dav/externalmembers,
http://www.iana.org/standards/dav/resourcetype, and
http://www.iana.org/standards/dav/supportedlock. The resource
http://www.foo.bar/container/index.html, a member of the "container"
collection, has nine properties defined on it,
http://www.foo.bar/boxschema/bigbox, http://www.foo.bar/boxschema/bigbox,
http://www.iana.org/standards/dav/creationdate, http://www.foo.bar/boxschema/author, DAV:creationdate,
http://www.iana.org/standards/dav/displayname, DAV:displayname, DAV:resourcetype, and DAV:supportedlock.
http://www.iana.org/standards/dav/get-content-length,
http://www.iana.org/standards/dav/get-content-type, The resource http://www.foo.bar/container/index.html, a member of
http://www.iana.org/standards/dav/get-etag, the "container" collection, has nine properties defined on it,
http://www.iana.org/standards/dav/get-last-modified, http://www.foo.bar/boxschema/bigbox, DAV:creationdate,
http://www.iana.org/standards/dav/resourcetype, and DAV:displayname, DAV:getcontentlength, DAV:getcontenttype,
http://www.iana.org/standards/dav/supportedlock. DAV:getetag, DAV:getlastmodified, DAV:resourcetype, and
DAV:supportedlock.
7.2 PROPPATCH 7.2 PROPPATCH
The PROPPATCH method processes instructions specified in the request The PROPPATCH method processes instructions specified in the request
body to set and/or remove properties defined on the resource body to set and/or remove properties defined on the resource
identified by Request-URI. identified by the Request-URI.
All DAV compliant resources MUST support the PROPPATCH method and All DAV compliant resources MUST support the PROPPATCH method and
MUST process instructions that are specified using the MUST process instructions that are specified using the
propertyupdate, set, and remove XML elements of the DAV schema. propertyupdate, set, and remove XML elements of the DAV schema.
Execution of the directives in this method is, of course, subject to Execution of the directives in this method is, of course, subject to
access control constraints. DAV compliant resources SHOULD support access control constraints. DAV compliant resources SHOULD support
the setting of arbitrary dead properties. the setting of arbitrary dead properties.
The request message body of a PROPPATCH method MUST contain at least The request message body of a PROPPATCH method MUST contain at least
one propertyupdate XML element. Instruction processing MUST occur in one propertyupdate XML element. Instruction processing MUST occur in
skipping to change at page 28, line 26 skipping to change at page 27, line 49
Execution of the directives in this method is, of course, subject to Execution of the directives in this method is, of course, subject to
access control constraints. DAV compliant resources SHOULD support access control constraints. DAV compliant resources SHOULD support
the setting of arbitrary dead properties. the setting of arbitrary dead properties.
The request message body of a PROPPATCH method MUST contain at least The request message body of a PROPPATCH method MUST contain at least
one propertyupdate XML element. Instruction processing MUST occur in one propertyupdate XML element. Instruction processing MUST occur in
the order instructions are received (i.e., from top to bottom). the order instructions are received (i.e., from top to bottom).
Instructions MUST either all be executed or none executed. Thus if Instructions MUST either all be executed or none executed. Thus if
any error occurs during processing all executed instructions MUST be any error occurs during processing all executed instructions MUST be
undone and a proper error result returned. Instruction processing undone and a proper error result returned. Instruction processing
details can be found in the definition of the set and remove details can be found in the definition of the set and remove
instructions in Section 11.13. instructions in section 11.13.
If PROPPATCH is invoked on a null resource (e.g., a deleted 7.2.1 Status Codes for use with Multi-Status
resource), an empty resource is created, and the PROPPATCH
directives are performed on this new resource.
7.2.1 Status Codes The following are examples of response codes one would expect to be
used in a Multi-Status response for this method. Note, however,
that unless explicitly prohibited any 2/3/4/5xx series response code
may be used in a Multi-Status response.
200 OK - The command succeeded. As there can be a mixture of sets 200 OK - The command succeeded. As there can be a mixture of sets
and removes in a body, a 201 Created seems inappropriate. and removes in a body, a 201 Created seems inappropriate.
403 Forbidden - The client, for reasons the server chooses not to 403 Forbidden - The client, for reasons the server chooses not to
specify, cannot alter one of the properties. specify, cannot alter one of the properties.
409 Conflict - The client has provided a value whose semantics are 409 Conflict - The client has provided a value whose semantics are
not appropriate for the property. This includes trying to set read- not appropriate for the property. This includes trying to set read-
only properties. only properties.
413 Request Entity Too Long - If a particular property is too long 423 Locked - The specified resource is locked and the client either
to be recorded then a composite XML error will be returned is not a lock owner or the lock type requires a lock token to be
indicating the offending property. submitted and the client did not submit it.
425 Insufficient Space on Resource - The server did not have
sufficient space to record the property.
7.2.2 Example 7.2.2 Example
>>Request >>Request
PROPPATCH /bar.html HTTP/1.1 PROPPATCH /bar.html HTTP/1.1
Host: www.foo.com Host: www.foo.com
Content-Type: text/xml Content-Type: text/xml
Content-Length: xxxx Content-Length: xxxx
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href="http://www.iana.org/standards/dav/" as="D"?> <?xml:namespace name="DAV:" as="D"?>
<?namespace href="http://www.w3.com/standards/z39.50/" as="Z"?> <?xml:namespace name="http://www.w3.com/standards/z39.50/" as="Z"?>
<D:propertyupdate> <D:propertyupdate>
<D:set> <D:set>
<D:prop> <D:prop>
<Z:authors> <Z:authors>
<Z:Author>Jim Whitehead</Z:Author> <Z:Author>Jim Whitehead</Z:Author>
<Z:Author>Roy Fielding</Z:Author> <Z:Author>Roy Fielding</Z:Author>
</Z:authors> </Z:authors>
</D:prop> </D:prop>
</D:set> </D:set>
<D:remove> <D:remove>
skipping to change at page 29, line 23 skipping to change at page 29, line 4
<Z:authors> <Z:authors>
<Z:Author>Jim Whitehead</Z:Author> <Z:Author>Jim Whitehead</Z:Author>
<Z:Author>Roy Fielding</Z:Author> <Z:Author>Roy Fielding</Z:Author>
</Z:authors> </Z:authors>
</D:prop> </D:prop>
</D:set> </D:set>
<D:remove> <D:remove>
<D:prop><Z:Copyright-Owner/></D:prop> <D:prop><Z:Copyright-Owner/></D:prop>
</D:remove> </D:remove>
</D:propertyupdate> </D:propertyupdate>
>>Response >>Response
HTTP/1.1 207 Multi-Status HTTP/1.1 207 Multi-Status
Content-Type: text/xml Content-Type: text/xml
Content-Length: xxxxx Content-Length: xxxxx
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href="http://www.iana.org/standards/dav/" as="D"?> <?xml:namespace name="DAV:" as="D"?>
<?namespace href="http://www.w3.com/standards/z39.50/" as="Z"?> <?xml:namespace name="http://www.w3.com/standards/z39.50/" as="Z"?>
<D:multistatus> <D:multistatus>
<D:response> <D:response>
<D:href>http://www.foo.com/bar</D:href> <D:href>http://www.foo.com/bar.html</D:href>
<D:propstat> <D:propstat>
<D:prop><Z:Authors/></D:prop> <D:prop><Z:Authors/></D:prop>
<D:status>HTTP/1.1 424 Method Failure</D:status> <D:status>HTTP/1.1 424 Method Failure</D:status>
</D:propstat> </D:propstat>
<D:propstat> <D:propstat>
<D:prop><Z:Copyright-Owner/></D:prop> <D:prop><Z:Copyright-Owner/></D:prop>
<D:status>HTTP/1.1 409 Conflict</D:status> <D:status>HTTP/1.1 409 Conflict</D:status>
</D:propstat> </D:propstat>
<D:responsedescription> Copyright Owner can not be deleted or <D:responsedescription> Copyright Owner can not be deleted or
altered.</D:responsedescription> altered.</D:responsedescription>
<D:response> </D:response>
</D:multistatus> </D:multistatus>
In this example, the client requests the server to set the value of In this example, the client requests the server to set the value of
the http://www.w3.com/standards/z39.50/Authors property, and to the http://www.w3.com/standards/z39.50/Authors property, and to
remove the property http://www.w3.com/standards/z39.50/Copyright- remove the property http://www.w3.com/standards/z39.50/Copyright-
Owner. Since the Copyright-Owner property could not be removed, no Owner. Since the Copyright-Owner property could not be removed, no
property modifications occur. The Method Failure status code for property modifications occur. The Method Failure status code for
the Authors property indicates this action would have succeeded if the Authors property indicates this action would have succeeded if
it were not for the conflict with removing the Copyright-Owner it were not for the conflict with removing the Copyright-Owner
property. property.
7.3 MKCOL Method 7.3 MKCOL Method
The MKCOL method is used to create a new collection. All DAV The MKCOL method is used to create a new collection. All DAV
compliant resources MUST support the MKCOL method. compliant resources MUST support the MKCOL method.
7.3.1 Request 7.3.1 Request
MKCOL creates a new collection resource at the location specified by MKCOL creates a new collection resource at the location specified by
the Request-URI. If the resource identified by the Request-URI is the Request-URI. If the resource identified by the Request-URI is
non-null then the MKCOL must fail. During MKCOL processing, a non-null then the MKCOL MUST fail. During MKCOL processing, a
server MUST make the Request-URI a member of its parent collection. server MUST make the Request-URI a member of its parent collection,
If no such ancestor exists, the method MUST fail. When the MKCOL unless the Request-URI is "/". If no such ancestor exists, the
operation creates a new collection resource, all ancestors MUST method MUST fail. When the MKCOL operation creates a new collection
already exist, or the method MUST fail with a 409 Conflict status resource, all ancestors MUST already exist, or the method MUST fail
code. For example, if a request to create collection /a/b/c/d/ is with a 409 Conflict status code. For example, if a request to
made, and neither /a/b/ nor /a/b/c/ exists, the request MUST fail. create collection /a/b/c/d/ is made, and neither /a/b/ nor /a/b/c/
exists, the request must fail.
When MKCOL is invoked without a request body, the newly created When MKCOL is invoked without a request body, the newly created
collection has no members. collection SHOULD have no members.
A MKCOL request message MAY contain a message body. The behavior of A MKCOL request message may contain a message body. The behavior of
a MKCOL request when the body is present is limited to creating a MKCOL request when the body is present is limited to creating
collections, members of a collection, bodies of members and collections, members of a collection, bodies of members and
properties on the collections or members. If the server receives a properties on the collections or members. If the server receives a
MKCOL request entity type it does not support or understand it MUST MKCOL request entity type it does not support or understand it MUST
respond with a 415 Unsupported Media Type status code. The exact respond with a 415 Unsupported Media Type status code. The exact
behavior of MKCOL for various request media types is undefined in behavior of MKCOL for various request media types is undefined in
this document, and will be specified in separate documents. this document, and will be specified in separate documents.
7.3.2 Response Codes 7.3.2 Response Codes
Responses from a MKCOL request are not cacheable, since MKCOL has Responses from a MKCOL request MUST NOT be cached as MKCOL has non-
non-idempotent semantics. idempotent semantics.
201 Created - The collection or structured resource was created in 201 Created - The collection or structured resource was created in
its entirety. its entirety.
403 Forbidden - This indicates at least one of two conditions: 1) 403 Forbidden - This indicates at least one of two conditions: 1)
The server does not allow the creation of collections at the given the server does not allow the creation of collections at the given
location in its namespace, and 2) The parent collection of the location in its namespace, or 2) the parent collection of the
Request-URI exists but cannot accept members. Request-URI exists but cannot accept members.
405 Method Not Allowed - MKCOL can only be executed on a 405 Method Not Allowed - MKCOL can only be executed on a
deleted/non-existent resource. deleted/non-existent resource.
409 Conflict - A collection cannot be made at the Request-URI until 409 Conflict - A collection cannot be made at the Request-URI until
one or more intermediate collections have been created. one or more intermediate collections have been created.
415 Unsupported Media Type- The server does not support the request 415 Unsupported Media Type- The server does not support the request
type of the body. type of the body.
423 Insufficient Space on Resource - The resource does not have 425 Insufficient Space on Resource - The resource does not have
sufficient space to record the state of the resource after the sufficient space to record the state of the resource after the
execution of this method. execution of this method.
7.3.3 Example 7.3.3 Example
This example creates a collection called /webdisc/xfiles/ on the This example creates a collection called /webdisc/xfiles/ on the
server www.server.org. server www.server.org.
>>Request >>Request
MKCOL /webdisc/xfiles/ HTTP/1.1 MKCOL /webdisc/xfiles/ HTTP/1.1
Host: www.server.org Host: www.server.org
>>Response >>Response
HTTP/1.1 201 Created HTTP/1.1 201 Created
7.4 ADDREF Method 7.4 GET, HEAD for Collections
The ADDREF method is used to add external members to a resource.
All DAV compliant collection resources MUST support the ADDREF
method. All other DAV compliant resources MAY support the ADDREF
method as appropriate.
7.4.1 The Request
The ADDREF method adds the URI specified in the Collection-Member
header as an external member to the collection specified by the
Request-URI.
It is not an error if the URI specified in the Collection-Member
header already exists as an external member of the collection.
However, after processing the ADDREF there MUST be only one instance
of the URI in the collection. If the URI specified in the
Collection-Member header already exists as an internal member of the
collection, the ADDREF method MUST fail with a 412 Precondition
Failed status code.
More than one Collection-Member request header MUST NOT be used with
the ADDREF method.
7.4.2 Example
>>Request
ADDREF /~ejw/dav/ HTTP/1.1
Host: www.ics.uci.edu
Collection-Member: http://www.iana.org/standards/dav/
>>Response
HTTP/1.1 204 No Content
This example adds the URI http://www.iana.org/standards/dav/ as an
external member resource of the collection
http://www.ics.uci.edu/~ejw/dav/.
7.5 DELREF Method
The DELREF method is used to remove external members from a
resource. All DAV compliant collection resources MUST support the
DELREF method. All other DAV compliant resources MUST support the
DELREF method only if they support the ADDREF method.
7.5.1 The Request
The DELREF method removes the URI specified in the Collection-Member
header from the collection specified by the Request-URI.
DELREFing a URI which is not a member of the collection is not an
error. DELREFing an internal member MUST fail with a 412
Precondition Failed status code.
More than one Collection-Member request header MUST NOT be used with
the DELREF method.
7.5.2 Example
>>Request
DELREF /~ejw/dav/ HTTP/1.1
Host: www.ics.udi.edu
Collection-Member: http://www.iana.org/standards/dav/
>>Response
HTTP/1.1 204 No Content
This example removes the URI http://www.iana.org/standards/dav/, an
external member resource, from the collection
http://www.ics.uci.edu/~ejw/dav/.
7.6 GET, HEAD for Collections
The semantics of GET are unchanged when applied to a collection, The semantics of GET are unchanged when applied to a collection,
since GET is defined as, "retrieve whatever information (in the form since GET is defined as, "retrieve whatever information (in the form
of an entity) is identified by the Request-URI" [Fielding et al., of an entity) is identified by the Request-URI" [Fielding et al.,
1997]. GET when applied to a collection MAY return the contents of 1997]. GET when applied to a collection may return the contents of
an "index.html" resource, a human-readable view of the contents of an "index.html" resource, a human-readable view of the contents of
the collection, or something else altogether. Hence it is possible the collection, or something else altogether. Hence it is possible
that the result of a GET on a collection will bear no correlation to that the result of a GET on a collection will bear no correlation to
the state of the collection. the membership of the collection.
Similarly, since the definition of HEAD is a GET without a response Similarly, since the definition of HEAD is a GET without a response
message body, the semantics of HEAD are unmodified when applied to message body, the semantics of HEAD are unmodified when applied to
collection resources. collection resources.
7.7 POST for Collections 7.5 POST for Collections
Since by definition the actual function performed by POST is Since by definition the actual function performed by POST is
determined by the server and often depends on the particular determined by the server and often depends on the particular
resource, the behavior of POST when applied to collections cannot be resource, the behavior of POST when applied to collections cannot be
meaningfully modified because it is largely undefined. Thus the meaningfully modified because it is largely undefined. Thus the
semantics of POST are unmodified when applied to a collection. semantics of POST are unmodified when applied to a collection.
7.8 DELETE 7.6 DELETE
7.8.1 DELETE for Non-Collection Resources 7.6.1 DELETE for Non-Collection Resources
If the DELETE method is issued to a non-collection resource which is If the DELETE method is issued to a non-collection resource which is
an internal member of a collection, then during DELETE processing a an internal member of a collection, then during DELETE processing a
server MUST remove the Request-URI from its parent collection. A server MUST remove the Request-URI from its parent collection.
server MAY remove the URI of a deleted resource from any collections
of which the resource is an external member.
7.8.2 DELETE for Collections 7.6.2 DELETE for Collections
The DELETE method on a collection MUST act as if a Depth = infinity The DELETE method on a collection MUST act as if a "Depth: infinity"
header was used on it. A client MUST NOT submit a Depth header on a header was used on it. A client MUST NOT submit a Depth header with
DELETE on a collection with any value but infinity. a DELETE on a collection with any value but infinity.
DELETE instructs that the collection specified in the request-URI, DELETE instructs that the collection specified in the request-URI
the records of its external member resources, and all its internal and all its internal member resources are to be deleted.
member resources, are to be deleted.
If any member cannot be deleted then all of the member's ancestors If any member cannot be deleted then all of the member's ancestors
MUST NOT be deleted, so as to maintain the namespace. MUST NOT be deleted, so as to maintain the namespace.
Any headers included with DELETE MUST be applied in processing every Any headers included with DELETE MUST be applied in processing every
resource to be deleted. resource to be deleted.
When the DELETE method has completed processing it MUST return a When the DELETE method has completed processing it MUST return a
consistent namespace. consistent namespace.
The response SHOULD be a Multi-Status response that describes the If an error occurs with a resource other than the resource
result of the DELETE on each affected resource. identified in the request URI then the response MUST be a 207 Multi-
Status. 424 Method Failure errors SHOULD NOT be in the 207 Multi-
Status. They can be safely left out because the client will know
that the ancestors of a resource could not be deleted when the
7.8.2.1 Example client receives an error for the ancestor's progeny. Additionally
204 No Content errors SHOULD NOT be returned in the 207 Multi-
Status. The reason for this prohibition is that 204 No Content is
the default success code.
7.6.2.1 Example
>>Request >>Request
DELETE /container/ HTTP/1.1 DELETE /container/ HTTP/1.1
Host: www.foo.bar Host: www.foo.bar
>>Response >>Response
HTTP/1.1 207 Multi-Status HTTP/1.1 207 Multi-Status
Content-Type: text/xml Content-Type: text/xml
Content-Length: xxxxx Content-Length: xxxxx
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href="http://www.iana.org/standards/dav/" as="d"?> <?xml:namespace name="DAV:" as="d"?>
<d:multistatus> <d:multistatus>
<d:response> <d:response>
<d:href>http://www.foo.bar/container/resource1</d:href>
<d:href>http://www.foo.bar/container/resource2</d:href>
<d:status>HTTP/1.1 200 OK</d:status>
</d:response>
<d:response>
<d:href>http://www.foo.bar/container/</d:href>
<d:status>HTTP/1.1 424 Method Failure</d:status>
</d:response>
<d:response>
<d:href>http://www.foo.bar/container/resource3</d:href> <d:href>http://www.foo.bar/container/resource3</d:href>
<d:status>HTTP/1.1 425 Locked</d:status> <d:status>HTTP/1.1 423 Locked</d:status>
</d:response> </d:response>
</d:multistatus> </d:multistatus>
In this example the attempt to delete In this example the attempt to delete
http://www.foo.bar/container/resource3 failed because it is locked, http://www.foo.bar/container/resource3 failed because it is locked,
and no lock token was submitted with the request. Consequently, the and no lock token was submitted with the request. Consequently, the
attempt to delete http://www.foo.bar/container/ also failed, but attempt to delete http://www.foo.bar/container/ also failed. Thus
resource1 and resource2 were deleted. Even though a Depth header has the client knows that the attempt to delete
not been included, a depth of infinity is assumed because the method http://ww.foo.bar/container/ must have also failed since the parent
is on a collection. As this example illustrates, DELETE processing can not be deleted unless its child has also been deleted. Even
need not be atomic. though a Depth header has not been included, a depth of infinity is
assumed because the method is on a collection.
7.9 PUT 7.7 PUT
7.9.1 PUT for Non-Collection Resources 7.7.1 PUT for Non-Collection Resources
A PUT performed on an existing resource replaces the GET response A PUT performed on an existing resource replaces the GET response
entity of the resource. Properties defined on the resource MAY be entity of the resource. Properties defined on the resource may be
recomputed during PUT processing but are not otherwise effected. recomputed during PUT processing but are not otherwise affected.
For example, if a server recognizes the content type of the request For example, if a server recognizes the content type of the request
body, it may be able to automatically extract information that could body, it may be able to automatically extract information that could
be profitably exposed as properties. be profitably exposed as properties.
A PUT that would result in the creation of a resource without an A PUT that would result in the creation of a resource without an
appropriately scoped parent collection MUST fail with a 409 appropriately scoped parent collection MUST fail with a 409
Conflict. Conflict.
7.9.2 PUT for Collections 7.7.2 PUT for Collections
As defined in the HTTP/1.1 specification [Fielding et al., 1997], As defined in the HTTP/1.1 specification [Fielding et al., 1997],
the "PUT method requests that the enclosed entity be stored under the "PUT method requests that the enclosed entity be stored under
the supplied Request-URI." Since submission of an entity the supplied Request-URI." Since submission of an entity
representing a collection would implicitly encode creation and representing a collection would implicitly encode creation and
deletion of resources, this specification intentionally does not deletion of resources, this specification intentionally does not
define a transmission format for creating a collection using PUT. define a transmission format for creating a collection using PUT.
Instead, the MKCOL method is defined to create collections. If a Instead, the MKCOL method is defined to create collections.
PUT is invoked on a collection resource it MUST fail.
When the PUT operation creates a new non-collection resource all When the PUT operation creates a new non-collection resource all
ancestors MUST already exist. If all ancestors do not exist, the ancestors MUST already exist. If all ancestors do not exist, the
method MUST fail with a 409 Conflict status code. For example, if method MUST fail with a 409 Conflict status code. For example, if
resource /a/b/c/d.html is to be created and /a/b/c/ does not exist, resource /a/b/c/d.html is to be created and /a/b/c/ does not exist,
then the request must fail. then the request must fail.
7.10 COPY Method 7.8 COPY Method
The COPY method creates a duplicate of the source resource, given by The COPY method creates a duplicate of the source resource, given by
the Request-URI, in the destination resource, given by the the Request-URI, in the destination resource, given by the
Destination header. The Destination header MUST be present. The Destination header. The Destination header MUST be present. The
exact behavior of the COPY method depends on the type of the source exact behavior of the COPY method depends on the type of the source
resource. resource.
Support for the COPY method does not guarantee the ability to copy a All WebDAV compliant resources MUST support the COPY method.
resource. For example, separate programs may control resources on However, support for the COPY method does not guarantee the ability
the same server. As a result, it may not even be possible to copy a to copy a resource. For example, separate programs may control
resource to a location that appears to be on the same server. resources on the same server. As a result, it may not be possible
to copy a resource to a location that appears to be on the same
server.
7.10.1 COPY for HTTP/1.1 resources 7.8.1 COPY for HTTP/1.1 resources
When the source resource is not a collection the body of the When the source resource is not a collection the result of the COPY
destination resource MUST be octet-for-octet identical to the body method is the creation of a new resource at the destination whose
of the source resource. Subsequent alterations to the destination state and behavior match that of the source resource as closely as
resource will not modify the source resource. Subsequent possible. However, the exact state and behavior of the destination
alterations to the source resource will not modify the destination resource depend on what information the source resource is able to
resource. Thus, all copies are performed "by-value". provide and what information the destination resource is able to
accept.
Subsequent alterations to the destination resource will not modify
the source resource. Subsequent alterations to the source resource
will not modify the destination resource.
All properties on the source resource MUST be duplicated on the All properties on the source resource MUST be duplicated on the
destination resource, subject to modifying headers and XML elements, destination resource, subject to modifying headers and XML elements,
following the definition for copying properties. following the definition for copying properties.
7.10.2 COPY for Properties 7.8.2 COPY for Properties
The following section defines how properties on a resource are The following section defines how properties on a resource are
handled during a COPY operation. handled during a COPY operation.
Live properties SHOULD be duplicated as identically behaving live Live properties SHOULD be duplicated as identically behaving live
properties at the destination resource. If a property cannot be properties at the destination resource. If a property cannot be
copied live, then its value MUST be duplicated, octet-for-octet, in copied live, then its value MUST be duplicated, octet-for-octet, in
an identically named, dead property on the destination resource.
The propertybehavior XML element can specify that properties are an identically named, dead property on the destination resource
copied on best effort, that all live properties MUST be successfully subject to the effects of the propertybehavior XML element.
copied or the method MUST fail, or that a specified list of live
properties MUST be successfully copied or the method must fail. The
propertybehavior XML element is defined in Section 11.12.
If a property on the source already exists on the destination The propertybehavior XML element can specify that properties are
resource and the Overwrite header is set to "T" then the property at copied on best effort, that all live properties must be successfully
the destination MUST be overwritten with the property from the copied or the method must fail, or that a specified list of live
source. If the Overwrite header is "F" and the previous situation properties must be successfully copied or the method must fail. The
exists, then the COPY MUST fail with a 412 Precondition Failed. propertybehavior XML element is defined in section 11.12.
7.10.3 COPY for Collections 7.8.3 COPY for Collections
The COPY method on a collection without a Depth header MUST act as The COPY method on a collection without a Depth header MUST act as
if a Depth header with value "infinity" was included. A client MAY if a Depth header with value "infinity" was included. A client may
submit a Depth header on a COPY on a collection with a value of "0" submit a Depth header on a COPY on a collection with a value of "0"
or "infinity". DAV compliant servers MUST support the "0" and or "infinity". DAV compliant servers MUST support the "0" and
"infinity" behaviors. "infinity" Depth header behaviors.
A COPY of depth infinity instructs that the collection specified in A COPY of depth infinity instructs that the collection specified in
the Request-URI and the records of its external member resources is the Request-URI is to be copied to the location specified in the
to be copied to the location specified in the Destination header, Destination header, and all its internal member resources are to be
and all its internal member resources are to be copied to a copied to a location relative to it, recursively through all levels
location relative to it, recursively through all levels of the of the collection hierarchy.
collection hierarchy.
A COPY of depth "0" only instructs that the collection, the A COPY of depth "0" only instructs that the collection and its
properties, and the records of its external members, not its properties but not its internal members, are to be copied.
internal members, are to be copied.
Any headers included with a COPY are to be applied in processing Any headers included with a COPY MUST be applied in processing every
every resource to be copied. resource to be copied with the exception of the Destination header.
The exception to this rule is the Destination header. This header The Destination header only specifies the destination for the
only specifies the destination for the Request-URI. When applied to Request-URI. When applied to members of the collection specified in
members of the collection specified in the request-URI the value of the request-URI the value of Destination is to be modified to
Destination is to be modified to reflect the current location in the reflect the current location in the hierarchy. So, if the request-
hierarchy. So, if the request-URI is "a" and the destination is "b" URI is /a/ and the destination is /b/ then when /a/c/d is processed
then when a/c/d is processed it MUST use a destination of b/c/d. it must use a destination of /b/c/d.
When the COPY method has completed processing it MUST have created a When the COPY method has completed processing it MUST have created a
consistent namespace at the destination. However, if an error consistent namespace at the destination. However, if an error
occurs while copying an internal member collection, all members of occurs while copying an internal member collection, the server MUST
this collection MUST NOT be copied. In this case, after detecting NOT copy any members of this collection. After detecting an error,
the error, the COPY operation SHOULD try to finish as much of the the COPY operation SHOULD try to finish as much of the original copy
original copy operation as possible. So, for example, if an operation as possible. So, for example, if an infinite depth copy
infinite depth copy operation is performed on collection /a/, which operation is performed on collection /a/, which contains collections
contains collections /a/b/ and /a/c/, and an error occurs copying /a/b/ and /a/c/, and an error occurs copying /a/b/, an attempt
/a/b/, an attempt should still be made to copy /a/c/. Similarly, should still be made to copy /a/c/. Similarly, after encountering an
after encountering an error copying a non-collection resource as error copying a non-collection resource as part of an infinite depth
part of an infinite depth copy, the server SHOULD try to finish as copy, the server SHOULD try to finish as much of the original copy
much of the original copy operation as possible. operation as possible.
The response is a Multi-Status status code with an entity body that If an error in executing the COPY method occurs with a resource
describes the result of the COPY on each affected resource. The other than the resource identified in the request URI then the
href XML element in the response refers to the resource that was to response MUST be a 207 Multi-Status.
be copied, not the resource that was created as a result of the
copy. In other words, each entry indicates whether the copy on the
resource specified in the href XML element succeeded or failed and
why.
The exception to this rule is for errors that occurred on the 424 Method Failure errors SHOULD NOT be returned in the 207 Multi-
destination. For example, if the destination was locked the Status from a COPY method. These responses can be safely omitted
response would indicate the destination URL and a 425 Locked error. because the client will know that the progeny of a resource could
not be copied when the client receives an error for the parent.
Additionally 201 Created/204 No Content response codes SHOULD NOT be
returned as values in 207 Multi-Status responses from COPY methods.
They, too, can be safely omitted because they are the default
success codes.
7.10.4 Type Interactions 7.8.4 COPY and the Overwrite Header
If the destination resource identifies a collection and the If a resource exists at the destination and the Overwrite header is
Overwrite header is "T", prior to performing the copy the server "T" then prior to performing the copy the server MUST perform a
MUST perform a DELETE operation on the collection. DELETE with Depth Infinity on the destination resource. If the
Overwrite header is set to "F" then the operation will fail.
7.10.5 Status Codes 7.8.5 Status Codes
201 Created - The source resource was successfully copied. The copy 201 Created - The source resource was successfully copied. The copy
operation resulted in the creation of a new resource. operation resulted in the creation of a new resource.
204 No Content - The source resource was successfully copied to a 204 No Content - The source resource was successfully copied to a
pre-existing destination resource. Since there is no entity body in pre-existing destination resource.
the response, 204 No Content is used instead of 200 OK.
412 Precondition Failed - This status code MUST be returned if the 412 Precondition Failed - The server was unable to maintain the
server was unable to maintain the liveness of the properties listed liveness of the properties listed in the propertybehavior XML
in the propertybehavior XML element, or if the Overwrite header is element or the Overwrite header is "F" and the state of the
"F", and the state of the destination resource is non-null. destination resource is non-null.
423 Insufficient Space on Resource - The destination resource does 423 Locked - The destination resource was locked.
425 Insufficient Space on Resource - The destination resource does
not have sufficient space to record the state of the resource after not have sufficient space to record the state of the resource after
the execution of this method. the execution of this method.
425 Locked - The destination resource was locked and either a valid
Lock-Token header was not submitted, or the Lock-Token header
identifies a lock held by another principal.
502 Bad Gateway - This may occur when the destination is on another 502 Bad Gateway - This may occur when the destination is on another
server and the destination server refuses to accept the resource. server and the destination server refuses to accept the resource.
7.10.6 Overwrite Example 7.8.6 Overwrite Example
This example shows resource This example shows resource
http://www.ics.uci.edu/~fielding/index.html being copied to the http://www.ics.uci.edu/~fielding/index.html being copied to the
location http://www.ics.uci.edu/users/f/fielding/index.html. The location http://www.ics.uci.edu/users/f/fielding/index.html. The
204 No Content status code indicates the existing resource at the 204 No Content status code indicates the existing resource at the
destination was overwritten. destination was overwritten.
>>Request >>Request
COPY /~fielding/index.html HTTP/1.1 COPY /~fielding/index.html HTTP/1.1
Host: www.ics.uci.edu Host: www.ics.uci.edu
Destination: http://www.ics.uci.edu/users/f/fielding/index.html Destination: http://www.ics.uci.edu/users/f/fielding/index.html
>>Response >>Response
HTTP/1.1 204 No Content HTTP/1.1 204 No Content
7.10.7 No Overwrite Example 7.8.7 No Overwrite Example
The following example shows the same copy operation being performed, The following example shows the same copy operation being performed,
except with the Overwrite header set to "F." A response of 412 but with the Overwrite header set to "F." A response of 412
Precondition Failed is returned because the destination resource has Precondition Failed is returned because the destination resource has
a non-null state. a non-null state.
>>Request >>Request
COPY /~fielding/index.html HTTP/1.1 COPY /~fielding/index.html HTTP/1.1
Host: www.ics.uci.edu Host: www.ics.uci.edu
Destination: http://www.ics.uci.edu/users/f/fielding/index.html Destination: http://www.ics.uci.edu/users/f/fielding/index.html
Overwrite: F Overwrite: F
>>Response >>Response
HTTP/1.1 412 Precondition Failed HTTP/1.1 412 Precondition Failed
7.10.8 Collection Example 7.8.8 Collection Example
>>Request >>Request
COPY /container/ HTTP/1.1 COPY /container/ HTTP/1.1
Host: www.foo.bar Host: www.foo.bar
Destination: http://www.foo.bar/othercontainer/ Destination: http://www.foo.bar/othercontainer/
Depth: infinity Depth: infinity
Content-Type: text/xml Content-Type: text/xml
Content-Length: xxxxx Content-Length: xxxxx
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href="http://www.iana.org/standards/dav/" as="d"?> <?xml:namespace name="DAV:" as="d"?>
<d:propertybehavior> <d:propertybehavior>
<d:keepalive>*</d:keepalive> <d:keepalive>*</d:keepalive>
</d:propertybehavior> </d:propertybehavior>
>>Response >>Response
HTTP/1.1 207 Multi-Status HTTP/1.1 207 Multi-Status
Content-Type: text/xml Content-Type: text/xml
Content-Length: xxxxx Content-Length: xxxxx
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href="http://www.iana.org/standards/dav/" as="d"?> <?xml:namespace name="DAV:" as="d"?>
<d:multistatus> <d:multistatus>
<d:response> <d:response>
<d:href>http://www.foo.bar/othercontainer/resource1</d:href>
<d:href>http://www.foo.bar/othercontainer/resource2</d:href>
<d:href>http://www.foo.bar/othercontainer/</d:href>
<d:status>HTTP/1.1 201 Created</d:status>
</d:response>
<d:response>
<d:href>http://www.foo.bar/othercontainer/R2/</d:href> <d:href>http://www.foo.bar/othercontainer/R2/</d:href>
<d:href>http://www.foo.bar/othercontainer/R2/D2</d:href>
<d:status>HTTP/1.1 412 Precondition Failed</d:status> <d:status>HTTP/1.1 412 Precondition Failed</d:status>
</d:response> </d:response>
</d:multistatus> </d:multistatus>
The Depth header is unnecessary as the default behavior of COPY on a The Depth header is unnecessary as the default behavior of COPY on a
collection is to act as if a "Depth: infinity" header had been collection is to act as if a "Depth: infinity" header had been
submitted. In this example most of the resources, along with the submitted. In this example most of the resources, along with the
collection, were copied successfully. However the collection R2 collection, were copied successfully. However the collection R2
failed, most likely due to a problem with maintaining the liveness failed, most likely due to a problem with maintaining the liveness
of properties (this is specified by the propertybehavior XML of properties (this is specified by the propertybehavior XML
element). Since an error occurred copying R2, R2's member D2 was not element). Because there was an error copying R2, none of R2's
copied. members were copied. However no errors were listed for those
members due to the error minimization rules given in section 7.8.3.
7.11 MOVE Method 7.9 MOVE Method
The MOVE operation on a non-collection resource is the logical The MOVE operation on a non-collection resource is the logical
equivalent of a copy (COPY) followed by a delete, where the actions equivalent of a copy (COPY) followed by a delete of the source,
are performed atomically. All DAV compliant resources MUST support where the actions are performed atomically. Consequently, the
the MOVE method. Destination header MUST be present on all MOVE methods and MUST
follow all COPY requirements for the COPY part of the MOVE method.
All DAV compliant resources MUST support the MOVE method. However,
support for the MOVE method does not guarantee the ability to move a
resource to a particular destination.
However, support for the MOVE method does not guarantee the ability For example, separate programs may actually control different sets
to move a resource to a particular destination. For example, of resources on the same server. Therefore, it may not be possible
separate programs may actually control different sets of resources to move a resource within a namespace that appears to belong to the
on the same server. Therefore, it may not even be possible to move same server.
a resource within a namespace that appears to belong to the same
server.
If a resource exists at the destination, the destination resource If a resource exists at the destination, the destination resource
will be DELETEd as a side effect of the MOVE operation, subject to will be DELETEd as a side-effect of the MOVE operation, subject to
the restrictions of the Overwrite header. the restrictions of the Overwrite header.
7.11.1 MOVE for Collections 7.9.1 MOVE for Properties
The behavior of properties on a MOVE, including the effects of the
propertybehavior XML element, MUST be the same as specified in
section 7.8.2.
7.9.2 MOVE for Collections
A MOVE of depth infinity instructs that the collection specified in A MOVE of depth infinity instructs that the collection specified in
the Request-URI, including the records of its external member the Request-URI be moved to the location specified in the
resources, is to be moved to the location specified in the
Destination header, and all its internal member resources are to be Destination header, and all its internal member resources are to be
moved to locations relative to it, recursively through all levels of moved to locations relative to it, recursively through all levels of
the collection hierarchy. the collection hierarchy.
The MOVE method on a collection MUST act as if a Depth "infinity" The MOVE method on a collection MUST act as if a Depth "infinity"
header was used on it. A client MUST NOT submit a Depth header on a header was used on it. A client MUST NOT submit a Depth header on a
MOVE on a collection with any value but "infinity". MOVE on a collection with any value but "infinity".
Any headers included with MOVE are to be applied in processing every Any headers included with MOVE MUST be applied in processing every
resource to be moved. resource to be moved with the exception of the Destination header.
The exception to this rule is the Destination header. The behavior The behavior of the Destination header is the same as given for COPY
of this header is the same as given for COPY on collections. on collections.
When the MOVE method has completed processing it MUST have created a When the MOVE method has completed processing it MUST have created a
consistent namespace on both the source and destination. However, if consistent namespace on both the source and destination. However, if
an error occurs while moving an internal member collection, all an error occurs while moving an internal member collection, the
members of the failed collection MUST NOT be moved. In this case, server MUST NOT move any members of the failed collection.. In this
after detecting the error, the move operation SHOULD try to finish case, after detecting the error, the move operation SHOULD try to
as much of the original move as possible. So, for example, if an finish as much of the original move as possible. So, for example,
infinite depth move is performed on collection /a/, which contains if an infinite depth move is performed on collection /a/, which
collections /a/b/ and /a/c/, and an error occurs moving /a/b/, an contains collections /a/b/ and /a/c/, and an error occurs moving
attempt should still be made to try moving /a/c/. Similarly, after /a/b/, an attempt should still be made to try moving /a/c/.
encountering an error moving a non-collection resource as part of an Similarly, after encountering an error moving a non-collection
infinite depth move, the server SHOULD try to finish as much of the resource as part of an infinite depth move, the server SHOULD try to
original move operation as possible. finish as much of the original move operation as possible.
As specified in the definition of MOVE, a MOVE of a collection over If an error occurs with a resource other than the resource
another collection causes the destination collection and all its identified in the request URI then the response MUST be a 207 Multi-
members to be deleted. Status.
The response is a Multi-Status response that describes the result of 424 Method Failure errors SHOULD NOT be returned as values in the
the MOVE on each affected resource. The href XML element in the 207 Multi-Status from a MOVE method. These errors can be safely
response refers to the resource that was to be moved, not the omitted because the client will know that the progeny of a resource
resource that was created as a result of the move. In other words, could not be moved when the client receives an error for the parent.
each entry indicates whether the move on the resource specified in Additionally 201 Created/204 No Content responses SHOULD NOT be
the href succeeded or failed and why. returned as values in 207 Multi-Status responses from MOVES. These
responses can be safely omitted because they are the default success
codes.
The exception to this rule is for errors that occurred on the 7.9.3 MOVE and the Overwrite Header
destination. For example, if the destination was locked the
response would indicate the destination URL and a 425 Locked error. If a resource exists at the destination and the Overwrite header is
"T" then prior to performing the move the server MUST perform a
DELETE with Depth infinity on the destination resource. If the
Overwrite header is set to "F" then the operation will fail.
7.9.4 Status Codes
7.11.2 Status Codes
201 Created - The source resource was successfully moved, and a new 201 Created - The source resource was successfully moved, and a new
resource was created at the destination. resource was created at the destination.
204 No Content - The move operation was successful, and the resource 204 No Content - The source resource was successfully moved to a
at the destination was overwritten. pre-existing destination resource.
412 Precondition Failed - This status code MUST be returned if the 412 Precondition Failed - The server was unable to maintain the
server was unable to maintain the liveness of the properties listed liveness of the properties listed in the propertybehavior XML
in the propertybehavior XML element, or if the Overwrite header is element or the Overwrite header is "F" and the state of the
"F", and the state of the destination resource is non-null. destination resource is non-null.
425 Locked - The source or the destination resource was locked and 423 Locked - The source or the destination resource was locked.
either a valid Lock-Token header was not submitted, or the Lock-
Token header identifies a lock held by another principal.
502 Bad Gateway - This may occur when the destination is on another 502 Bad Gateway - This may occur when the destination is on another
server and the destination server refuses to accept the resource. server and the destination server refuses to accept the resource.
7.11.3 Non-Collection Example 7.9.5 Non-Collection Example
This example shows resource This example shows resource
http://www.ics.uci.edu/~fielding/index.html being moved to the http://www.ics.uci.edu/~fielding/index.html being moved to the
location http://www.ics.uci.edu/users/f/fielding/index.html. The location http://www.ics.uci.edu/users/f/fielding/index.html. The
contents of the destination resource would have been overwritten if contents of the destination resource would have been overwritten if
the destination resource had been non-null. In this case, since the destination resource had been non-null. In this case, since
there was nothing at the destination resource, the response code is there was nothing at the destination resource, the response code is
201 Created. 201 Created.
>>Request >>Request
MOVE /~fielding/index.html HTTP/1.1 MOVE /~fielding/index.html HTTP/1.1
Host: www.ics.uci.edu Host: www.ics.uci.edu
Destination: http://www.ics.uci.edu/users/f/fielding/index.html Destination: http://www.ics.uci.edu/users/f/fielding/index.html
>>Response >>Response
HTTP/1.1 201 Created HTTP/1.1 201 Created
Location: http://www.ics.uci.edu/users/f/fielding/index.html Location: http://www.ics.uci.edu/users/f/fielding/index.html
7.11.4 Collection Example 7.9.6 Collection Example
>>Request >>Request
MOVE /container/ HTTP/1.1 MOVE /container/ HTTP/1.1
Host: www.foo.bar Host: www.foo.bar
Destination: http://www.foo.bar/othercontainer/ Destination: http://www.foo.bar/othercontainer/
Overwrite: F Overwrite: F
Lock-Token: <opaquelocktoken:fe184f2e-6eec-41d0-c765-01adc56e6bb4>, If: (<opaquelocktoken:fe184f2e-6eec-41d0-c765-01adc56e6bb4>)
<opaquelocktoken:e454f3f3-acdc-452a-56c7-00a5c91e4b77> (<opaquelocktoken:e454f3f3-acdc-452a-56c7-00a5c91e4b77>)
Content-Type: text/xml Content-Type: text/xml
Content-Length: xyz Content-Length: xyz
Authorization: Digest username="rohit",
realm="rohit@www.foo.bar", nonce="...",
uri="/container/", response="...",
opaque="..."
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href="http://www.iana.org/standards/dav/" as="d"?> <?xml:namespace name="DAV:" as="d"?>
<d:propertybehavior> <d:propertybehavior>
<d:keepalive>*</d:keepalive> <d:keepalive>*</d:keepalive>
</d:propertybehavior> </d:propertybehavior>
>>Response >>Response
HTTP/1.1 207 Multi-Status HTTP/1.1 207 Multi-Status
Content-Type: text/xml Content-Type: text/xml
Content-Length: zzz Content-Length: zzz
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href="http://www.iana.org/standards/dav/" as="d"?> <?xml:namespace name="DAV:" as="d"?>
<d:multistatus> <d:multistatus>
<d:response> <d:response>
<d:href>http://www.foo.bar/container/resource1</d:href>
<d:href>http://www.foo.bar/container/resource2</d:href>
<d:href>http://www.foo.bar/container/</d:href>
<d:status>HTTP/1.1 204 No Content</d:status>
</d:response>
<d:response>
<d:href>http://www.foo.bar/container/C2/R2</d:href>
<d:status>HTTP/1.1 424 Method Failure</d:status>
<d:response>
<d:href>http://www.foo.bar/othercontainer/C2/</d:href> <d:href>http://www.foo.bar/othercontainer/C2/</d:href>
<d:status>HTTP/1.1 425 Locked</d:status> <d:status>HTTP/1.1 423 Locked</d:status>
</d:response> </d:response>
</d:multistatus> </d:multistatus>
In this example the client has submitted a number of lock tokens In this example the client has submitted a number of lock tokens
with the request. A lock token will need to be submitted for every with the request. A lock token will need to be submitted for every
resource, both source and destination, anywhere in the scope of the resource, both source and destination, anywhere in the scope of the
method, that is locked. In this case the proper lock token was not method, that is locked. In this case the proper lock token was not
submitted for the destination http://www.foo.bar/othercontainer/C2/. submitted for the destination http://www.foo.bar/othercontainer/C2/.
This means that the resource /container/C2/ could not be moved. As This means that the resource /container/C2/ could not be moved.
the attempt to move /container/C2/ failed then the resource Because there was an error copying /container/C2/, none of
/container/C2/R2 MUST also fail since it is a child of /container/C2's members were copied. However no errors were listed
/container/C2/. for those members due to the error minimization rules given in
section 7.8.3. User agent authentication has previously occurred
via a mechanism outside the scope of the HTTP protocol, in an
underlying transport layer.
7.12 LOCK Method 7.10 LOCK Method
The following sections describe the LOCK method, which is used to The following sections describe the LOCK method, which is used to
take out a lock of any access type. These sections on the LOCK take out a lock of any access type. These sections on the LOCK
method describe only those semantics that are specific to the LOCK method describe only those semantics that are specific to the LOCK
method and are independent of the access type of the lock being method and are independent of the access type of the lock being
requested. requested.
7.12.1 Operation Any resource which supports the LOCK method MUST, at minimum,
support the XML request and response formats defined herein.
7.10.1 Operation
A LOCK method invocation creates the lock specified by the lockinfo A LOCK method invocation creates the lock specified by the lockinfo
XML element on the Request-URI. Lock method requests SHOULD have a XML element on the Request-URI. Lock method requests SHOULD have a
XML request body which contains an owner XML element for this lock XML request body which contains an owner XML element for this lock
request, unless this is a refresh request. The LOCK request MAY have request, unless this is a refresh request. The LOCK request may have
a Timeout header. a Timeout header.
A successful response to a lock invocation MUST include Lock-Token Clients MUST assume that locks may arbitrarily disappear at any
and Timeout headers. Clients MUST assume that locks may arbitrarily time, regardless of the value given in the Timeout header. The
disappear at any time, regardless of the value given in the Timeout Timeout header only indicates the behavior of the server if
header. The Timeout header only indicates the behavior of the "extraordinary" circumstances do not occur. For example, an
server if "extraordinary" circumstances do not occur. For example, administrator may remove a lock at any time or the system may crash
an administrator may remove a lock at any time or the system may in such a way that it loses the record of the lock's existence. The
crash in such a way that it loses the record of the lock's response MUST contain the value of the lockdiscovery property in a
existence. The response MUST also contain the value of the prop XML element.
lockdiscovery property in a prop XML element.
7.12.2 The Effect of Locks on Properties and Collections 7.10.2 The Effect of Locks on Properties and Collections
The scope of a lock is the entire state of the resource, including The scope of a lock is the entire state of the resource, including
its body and associated properties. As a result, a lock on a its body and associated properties. As a result, a lock on a
resource also locks the resource's properties. resource MUST also lock the resource's properties.
For collections, a lock also affects the ability to add or remove For collections, a lock also affects the ability to add or remove
members. The nature of the effect depends upon the type of access members. The nature of the effect depends upon the type of access
control involved. control involved.
7.12.3 Locking Replicated Resources 7.10.3 Locking Replicated Resources
Some servers automatically replicate resources across multiple URLs. Some servers automatically replicate resources across multiple URLs.
In such a circumstance the server MAY only accept a lock on one of In such a circumstance the server MUST only accept a lock on one of
the URLs if the server can guarantee that the lock will be honored the URLs if the server can guarantee that the lock will be honored
across all the URLs. across all the URLs.
7.12.4 Depth and Locking 7.10.4 Depth and Locking
The Depth header MAY be used with the LOCK method. Values other The Depth header may be used with the LOCK method. Values other
than 0 or infinity MUST NOT be used with the Depth header. than 0 or infinity MUST NOT be used with the Depth header on a LOCK
method. All resources that support the LOCK method MUST support the
Depth header.
A Depth header of value 0 means to just lock the resource specified A Depth header of value 0 means to just lock the resource specified
by the request-URI. by the request-URI.
If the Depth header is set to infinity then the resource specified If the Depth header is set to infinity then the resource specified
in the request-URI along with all its internal members, all the way in the request-URI along with all its internal members, all the way
down the hierarchy, are to be locked. A successful result will down the hierarchy, are to be locked. A successful result MUST
return a single lock token which represents all the resources that return a single lock token which represents all the resources that
have been locked. If an UNLOCK is executed on this token, all have been locked. If an UNLOCK is successfully executed on this
associated resources are unlocked. If the lock cannot be granted to token, all associated resources are unlocked. If the lock cannot be
all resources, a 409 Conflict status code MUST be returned with a granted to all resources, a 409 Conflict status code MUST be
response entity body containing a multistatus XML element describing returned with a response entity body containing a multistatus XML
which resource(s) prevented the lock from being granted. Hence, element describing which resource(s) prevented the lock from being
partial success is not an option. Either the entire hierarchy is granted. Hence, partial success is not an option. Either the
locked or no resources are locked. entire hierarchy is locked or no resources are locked.
7.12.5 Interaction with other Methods If no depth header is submitted on a LOCK request then the request
MUST act as if a Depth of infinity had been submitted.
7.10.5 Interaction with other Methods
The interaction of a LOCK with various methods is dependent upon the The interaction of a LOCK with various methods is dependent upon the
lock type. However, independent of lock type, a successful DELETE lock type. However, independent of lock type, a successful DELETE
of a resource MUST cause all of its locks to be removed. of a resource MUST cause all of its locks to be removed.
7.12.6 Lock Compatibility Table 7.10.6 Lock Compatibility Table
The table below describes the behavior that occurs when a lock The table below describes the behavior that occurs when a lock
request is made on a resource. request is made on a resource.
Current lock state/ Shared Lock Exclusive Current lock state/ Shared Lock Exclusive
Lock request Lock Lock request Lock
None True True None True True
Shared Lock True False Shared Lock True False
Exclusive Lock False False* Exclusive Lock False False*
Legend: True = lock MAY be granted. False = lock MUST NOT be Legend: True = lock may be granted. False = lock MUST NOT be
granted. *=if the principal requesting the lock is the owner of the granted. *=if the principal requesting the lock is the owner of the
lock, the lock MUST be regranted. lock, the lock must be refreshed.
The current lock state of a resource is given in the leftmost The current lock state of a resource is given in the leftmost
column, and lock requests are listed in the first row. The column, and lock requests are listed in the first row. The
intersection of a row and column gives the result of a lock request. intersection of a row and column gives the result of a lock request.
For example, if a shared lock is held on a resource, and an For example, if a shared lock is held on a resource, and an
exclusive lock is requested, the table entry is "false", indicating exclusive lock is requested, the table entry is "false", indicating
the lock must not be granted. the lock must not be granted.
If an exclusive or shared lock is re-requested by the principal who If an exclusive or shared lock is re-requested by the principal who
owns the lock, the lock MUST be regranted. If the lock is owns the lock, the lock MUST be refreshed.
regranted, the same lock token that was previously issued MUST be
returned.
7.12.7 Lock Response 7.10.7 Status Codes
A successful lock response MUST contain a Lock-Token response 200 Success - The lock request succeeded and the value of the
header, a Timeout header and a prop XML element in the response body lockdiscovery property is included in the body.
which contains the value of the lockdiscovery property.
7.12.8 Status Codes 412 Precondition Failed - The included lock token was not
412 Precondition Failed - The included Lock-Token was not
enforceable on this resource or the server could not satisfy the enforceable on this resource or the server could not satisfy the
request in the lockinfo XML element. request in the lockinfo XML element.
425 Locked - The resource is locked, so the method has been 423 Locked - The resource is locked, so the method has been
rejected. rejected.
7.12.9 Example - Simple Lock Request 7.10.8 Example - Simple Lock Request
>>Request >>Request
LOCK /workspace/webdav/proposal.doc HTTP/1.1 LOCK /workspace/webdav/proposal.doc HTTP/1.1
Host: webdav.sb.aol.com Host: webdav.sb.aol.com
Timeout: Infinite, Second-4100000000 Timeout: Infinite, Second-4100000000
Content-Type: text/xml Content-Type: text/xml
Content-Length: xyz Content-Length: xyz
Authorization: Digest username="ejw", Authorization: Digest username="ejw",
realm="ejw@webdav.sb.aol.com", nonce="...", realm="ejw@webdav.sb.aol.com", nonce="...",
uri="/workspace/webdav/proposal.doc", uri="/workspace/webdav/proposal.doc",
response="...", opaque="..." response="...", opaque="..."
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href="http://www.iana.org/standards/dav/" as="D"?> <?xml:namespace name="DAV:" as="D"?>
<D:lockinfo> <D:lockinfo>
<D:locktype><D:write/></D:locktype>
<D:lockscope><D:exclusive/></D:lockscope> <D:lockscope><D:exclusive/></D:lockscope>
<D:locktype><D:write/></D:locktype>
<D:owner> <D:owner>
<D:href>http://www.ics.uci.edu/~ejw/contact.html</D:href> <D:href>http://www.ics.uci.edu/~ejw/contact.html</D:href>
</D:owner> </D:owner>
</D:lockinfo> </D:lockinfo>
>>Response >>Response
HTTP/1.1 200 OK HTTP/1.1 200 OK
Lock-Token: <opaquelocktoken:e71d4fae-5dec-22d6-fea5-00a0c91e6be4>
Timeout: Second-604800
Content-Type: text/xml Content-Type: text/xml
Content-Length: xxxxx Content-Length: xxxxx
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href ="http://www.iana.org/standards/dav/" as="D"?> <?xml:namespace name ="DAV:" as="D"?>
<D:prop> <D:prop>
<D:lockdiscovery> <D:lockdiscovery>
<D:activelock> <D:activelock>
<D:locktype><D:write/></D:locktype> <D:locktype><D:write/></D:locktype>
<D:lockscope><D:exclusive/></D:lockscope> <D:lockscope><D:exclusive/></D:lockscope>
<D:depth>Infinity</D:depth>
<D:owner> <D:owner>
<D:href>http://www.ics.uci.edu/~ejw/contact.html</D:href> <D:href>
http://www.ics.uci.edu/~ejw/contact.html
</D:href>
</D:owner> </D:owner>
<D:timeout>Second-604800</D:timeout> <D:timeout>Second-604800</D:timeout>
<D:locktoken> <D:locktoken>
<D:href> <D:href>
opaquelocktoken:e71d4fae-5dec-22d6-fea5-00a0c91e6be4 opaquelocktoken:e71d4fae-5dec-22d6-fea5-00a0c91e6be4
</D:href> </D:href>
</D:locktoken> </D:locktoken>
</D:activelock> </D:activelock>
</D:lockdiscovery> </D:lockdiscovery>
</D:prop> </D:prop>
skipping to change at page 46, line 11 skipping to change at page 44, line 4
</D:owner> </D:owner>
<D:timeout>Second-604800</D:timeout> <D:timeout>Second-604800</D:timeout>
<D:locktoken> <D:locktoken>
<D:href> <D:href>
opaquelocktoken:e71d4fae-5dec-22d6-fea5-00a0c91e6be4 opaquelocktoken:e71d4fae-5dec-22d6-fea5-00a0c91e6be4
</D:href> </D:href>
</D:locktoken> </D:locktoken>
</D:activelock> </D:activelock>
</D:lockdiscovery> </D:lockdiscovery>
</D:prop> </D:prop>
This example shows the successful creation of an exclusive write This example shows the successful creation of an exclusive write
lock on resource lock on resource
http://webdav.sb.aol.com/workspace/webdav/proposal.doc. The http://webdav.sb.aol.com/workspace/webdav/proposal.doc. The
resource http://www.ics.uci.edu/~ejw/contact.html contains contact resource http://www.ics.uci.edu/~ejw/contact.html contains contact
information for the owner of the lock. The server has an activity- information for the owner of the lock. The server has an activity-
based timeout policy in place on this resource, which causes the based timeout policy in place on this resource, which causes the
lock to automatically be removed after 1 week (604800 seconds). The lock to automatically be removed after 1 week (604800 seconds).
response has a Lock-Token header that gives the lock token URL that Note that the nonce, response, and opaque fields have not been
uniquely identifies the lock created by this lock request. Note calculated in the Authorization request header.
that the nonce, response, and opaque fields have not been calculated
in the Authorization request header.
7.12.10 Example - Refreshing a Write Lock 7.10.9 Example - Refreshing a Write Lock
>>Request >>Request
LOCK /workspace/webdav/proposal.doc HTTP/1.1 LOCK /workspace/webdav/proposal.doc HTTP/1.1
Host: webdav.sb.aol.com Host: webdav.sb.aol.com
Timeout: Infinite, Second-4100000000 Timeout: Infinite, Second-4100000000
Lock-Token: <opaquelocktoken:e71d4fae-5dec-22d6-fea5-00a0c91e6be4> If: (<opaquelocktoken:e71d4fae-5dec-22d6-fea5-00a0c91e6be4>)
Authorization: Digest username="ejw", Authorization: Digest username="ejw",
realm="ejw@webdav.sb.aol.com", nonce="...", realm="ejw@webdav.sb.aol.com", nonce="...",
uri="/workspace/webdav/proposal.doc", uri="/workspace/webdav/proposal.doc",
response="...", opaque="..." response="...", opaque="..."
>>Response >>Response
HTTP/1.1 200 OK HTTP/1.1 200 OK
Lock-Token: <opaquelocktoken:e71d4fae-5dec-22d6-fea5-00a0c91e6be4>
Timeout: Second-604800
Content-Type: text/xml Content-Type: text/xml
Content-Length: xxxxx Content-Length: xxxxx
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href ="http://www.iana.org/standards/dav/" as="D"?> <?xml:namespace name="DAV:" as="D"?>
<D:prop> <D:prop>
<D:lockdiscovery> <D:lockdiscovery>
<D:activelock> <D:activelock>
<D:locktype><D:write/></D:locktype> <D:locktype><D:write/></D:locktype>
<D:lockscope><D:exclusive/></D:lockscope> <D:lockscope><D:exclusive/></D:lockscope>
<D:depth>Infinity</D:depth>
<D:owner> <D:owner>
<D:href>http://www.ics.uci.edu/~ejw/contact.html</D:href> <D:href>
http://www.ics.uci.edu/~ejw/contact.html
</D:href>
</D:owner> </D:owner>
<D:timeout>Second-604800</D:timeout> <D:timeout>Second-604800</D:timeout>
<D:locktoken> <D:locktoken>
<D:href> <D:href>
opaquelocktoken:e71d4fae-5dec-22d6-fea5-00a0c91e6be4 opaquelocktoken:e71d4fae-5dec-22d6-fea5-00a0c91e6be4
</D:href> </D:href>
</D:locktoken> </D:locktoken>
</D:activelock> </D:activelock>
</D:lockdiscovery> </D:lockdiscovery>
</D:prop> </D:prop>
skipping to change at page 47, line 12 skipping to change at page 45, line 4
</D:owner> </D:owner>
<D:timeout>Second-604800</D:timeout> <D:timeout>Second-604800</D:timeout>
<D:locktoken> <D:locktoken>
<D:href> <D:href>
opaquelocktoken:e71d4fae-5dec-22d6-fea5-00a0c91e6be4 opaquelocktoken:e71d4fae-5dec-22d6-fea5-00a0c91e6be4
</D:href> </D:href>
</D:locktoken> </D:locktoken>
</D:activelock> </D:activelock>
</D:lockdiscovery> </D:lockdiscovery>
</D:prop> </D:prop>
This request would refresh the lock, resetting any time outs. This request would refresh the lock, resetting any time outs.
Notice that the client asked for an infinite time out but the server Notice that the client asked for an infinite time out but the server
choose to ignore the request. In this example, the nonce, response, choose to ignore the request. In this example, the nonce, response,
and opaque fields have not been calculated in the Authorization and opaque fields have not been calculated in the Authorization
request header. request header.
7.12.11 Example - Multi-Resource Lock Request 7.10.10 Example - Multi-Resource Lock Request
>>Request >>Request
LOCK /webdav/ HTTP/1.1 LOCK /webdav/ HTTP/1.1
Host: webdav.sb.aol.com Host: webdav.sb.aol.com
Timeout: Infinite, Second-4100000000 Timeout: Infinite, Second-4100000000
Depth: infinity Depth: infinity
Authorization: Digest username="ejw", Authorization: Digest username="ejw",
realm="ejw@webdav.sb.aol.com", nonce="...", realm="ejw@webdav.sb.aol.com", nonce="...",
uri="/workspace/webdav/proposal.doc", uri="/workspace/webdav/proposal.doc",
response="...", opaque="..." response="...", opaque="..."
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href="http://www.iana.org/standards/dav/" as="D"?> <?xml:namespace name="DAV:" as="D"?>
<D:lockinfo> <D:lockinfo>
<D:locktype><D:write/></D:locktype> <D:locktype><D:write/></D:locktype>
<D:lockscope><D:exclusive/></D:lockscope> <D:lockscope><D:exclusive/></D:lockscope>
<D:owner> <D:owner>
<D:href>http://www.ics.uci.edu/~ejw/contact.html</D:href> <D:href>http://www.ics.uci.edu/~ejw/contact.html</D:href>
</D:owner> </D:owner>
</D:lockinfo> </D:lockinfo>
>>Response >>Response
HTTP/1.1 207 Multistatus HTTP/1.1 207 Multi-Status
Content-Type: text/xml Content-Type: text/xml
Content-Length: xxxxx Content-Length: xxxxx
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href="http://www.iana.org/standards/dav/" as="D"?> <?xml:namespace name="DAV:" as="D"?>
<D:multistatus> <D:multistatus>
<D:response> <D:response>
<D:href>http://webdav.sb.aol.com/webdav/proposal.doc</D:href>
<D:href>http://webdav.sb.aol.com/webdav/</D:href>
<D:status>HTTP/1.1 424 Method Failure</D:status>
</D:response>
<D:response>
<D:href>http://webdav.sb.aol.com/webdav/secret</D:href> <D:href>http://webdav.sb.aol.com/webdav/secret</D:href>
<D:status>HTTP/1.1 403 Forbidden</D:status> <D:status>HTTP/1.1 403 Forbidden</D:status>
</D:response> </D:response>
</D:multistatus> </D:multistatus>
This example shows a request for an exclusive write lock on a This example shows a request for an exclusive write lock on a
collection and all its children. In this request, the client has collection and all its children. In this request, the client has
specified that it desires an infinite length lock, if available, specified that it desires an infinite length lock, if available,
otherwise a timeout of 4.1 billion seconds, if available. The otherwise a timeout of 4.1 billion seconds, if available. The
request entity body contains the contact information for the request entity body contains the contact information for the
principal taking out the lock, in this case a web page URL. principal taking out the lock, in this case a web page URL.
The 424 Method Failure indicates that a lock was not taken out on The error is a 403 Forbidden response on the resource
these resources due to an error elsewhere. Note that this does not
mean that a lock would have succeeded on these resources had the
other error not occurred. It only means that another error has
occurred and so the entire method has been aborted. The error is a
403 Forbidden response on the resource
http://webdav.sb.aol.com/webdav/secret. Because this resource could http://webdav.sb.aol.com/webdav/secret. Because this resource could
not be locked, none of the resources were locked. not be locked, none of the resources were locked.
In this example, the nonce, response, and opaque fields have not In this example, the nonce, response, and opaque fields have not
been calculated in the Authorization request header. been calculated in the Authorization request header.
7.13 UNLOCK Method 7.11 UNLOCK Method
The UNLOCK method removes the lock identified by the lock token in The UNLOCK method removes the lock identified by the lock token in
the Lock-Token header from the Request-URI, and all other resources the Lock-Token request header from the Request-URI, and all other
included in the lock. resources included in the lock. If all resources which have been
locked under the submitted lock token can not be unlocked then the
UNLOCK request MUST fail.
Any DAV compliant resource which supports the LOCK method MUST Any DAV compliant resource which supports the LOCK method MUST
support the UNLOCK method. support the UNLOCK method.
7.13.1 Example 7.11.1 Example
>>Request >>Request
UNLOCK /workspace/webdav/info.doc HTTP/1.1 UNLOCK /workspace/webdav/info.doc HTTP/1.1
Host: webdav.sb.aol.com Host: webdav.sb.aol.com
Lock-Token:<opaquelocktoken:a515cfa4-5da4-22e1-f5b5-00a0451e6bf7> Lock-Token: (<opaquelocktoken:a515cfa4-5da4-22e1-f5b5-00a0451e6bf7>)
Authorization: Digest username="ejw", Authorization: Digest username="ejw",
realm="ejw@webdav.sb.aol.com", nonce="...", realm="ejw@webdav.sb.aol.com", nonce="...",
uri="/workspace/webdav/proposal.doc", uri="/workspace/webdav/proposal.doc",
response="...", opaque="..." response="...", opaque="..."
>>Response >>Response
HTTP/1.1 204 No Content HTTP/1.1 204 No Content
In this example, the lock identified by the lock token In this example, the lock identified by the lock token
"opaquelocktoken:a515cfa4-5da4-22e1-f5b5-00a0451e6bf7" is "opaquelocktoken:a515cfa4-5da4-22e1-f5b5-00a0451e6bf7" is
successfully removed from the resource successfully removed from the resource
http://webdav.sb.aol.com/workspace/webdav/info.doc. If this lock http://webdav.sb.aol.com/workspace/webdav/info.doc. If this lock
included more than just one resource, the lock is removed from all included more than just one resource, the lock is removed from all
resources included in the lock. The 204 status code is used instead resources included in the lock. The 204 status code is used instead
of 200 OK because there is no response entity body. of 200 OK because there is no response entity body.
In this example, the nonce, response, and opaque fields have not In this example, the nonce, response, and opaque fields have not
been calculated in the Authorization request header. been calculated in the Authorization request header.
skipping to change at page 49, line 17 skipping to change at page 47, line 7
http://webdav.sb.aol.com/workspace/webdav/info.doc. If this lock http://webdav.sb.aol.com/workspace/webdav/info.doc. If this lock
included more than just one resource, the lock is removed from all included more than just one resource, the lock is removed from all
resources included in the lock. The 204 status code is used instead resources included in the lock. The 204 status code is used instead
of 200 OK because there is no response entity body. of 200 OK because there is no response entity body.
In this example, the nonce, response, and opaque fields have not In this example, the nonce, response, and opaque fields have not
been calculated in the Authorization request header. been calculated in the Authorization request header.
8 HTTP Headers for Distributed Authoring 8 HTTP Headers for Distributed Authoring
8.1 Collection-Member Header 8.1 DAV Header
CollectionMember = "Collection-Member" ":" absoluteURI ;
absoluteURI is defined in section 3.2.1 of [Fielding et al., 1997]
The Collection-Member header specifies the URI of an external
resource to be added/deleted to/from a collection.
8.2 DAV Header
DAV = "DAV" ":" ["1"] [",2"] ["," 1#extend] DAV = "DAV" ":" "1" [",2"] ["," 1#extend]
This header indicates that the resource supports the DAV schema and This header indicates that the resource supports the DAV schema and
protocol as specified. All DAV compliant resources MUST return the protocol as specified. All DAV compliant resources MUST return the
DAV header on all OPTIONS responses. DAV header on all OPTIONS responses.
The value is a list of all compliance classes that the resource The value is a list of all compliance classes that the resource
supports. Note that above a comma has already been added to the 2. supports. Note that above a comma has already been added to the 2.
This is because a resource can not be level 2 compliant unless it is This is because a resource can not be level 2 compliant unless it is
also level 1 compliant. Please refer to Section 13 for more details. also level 1 compliant. Please refer to section 14 for more details.
In general, however, support for one compliance class does not In general, however, support for one compliance class does not
entail support for any other. entail support for any other.
8.3 Depth Header 8.2 Depth Header
Depth = "Depth" ":" ("0" | "1" | "infinity") Depth = "Depth" ":" ("0" | "1" | "infinity")
The Depth header is used with methods executed on resources which The Depth header is used with methods executed on resources which
could potentially have internal members to indicate whether the could potentially have internal members to indicate whether the
method is to be applied only to the resource (Depth = 0), to the method is to be applied only to the resource (Depth = 0), to the
resource and its immediate children, (Depth = 1), or the resource resource and its immediate children, (Depth = 1), or the resource
and all its progeny (Depth = infinity). and all its progeny (Depth = infinity).
The Depth header is only supported if a method's definition The Depth header is only supported if a method's definition
explicitly provides for such support. explicitly provides for such support.
The following rules are the default behavior for any method that The following rules are the default behavior for any method that
supports the Depth header. A method MAY override these defaults by supports the Depth header. A method may override these defaults by
defining different behavior in its definition. defining different behavior in its definition.
Methods which support the Depth header MAY choose not to support all Methods which support the Depth header may choose not to support all
of the header's values and MAY define, on a case by case basis, the of the header's values and may define, on a case by case basis, the
behavior of the method if a Depth header is not present. For behavior of the method if a Depth header is not present. For
example, the MOVE method only supports Depth = infinity and if a example, the MOVE method only supports Depth = infinity and if a
Depth header is not present will act as if a Depth = infinity header Depth header is not present will act as if a Depth = infinity header
had been applied. had been applied.
Clients MUST NOT rely upon methods executing on members of their Clients MUST NOT rely upon methods executing on members of their
hierarchies in any particular order or on the execution being hierarchies in any particular order or on the execution being atomic
atomic. Note that methods MAY provide guarantees on ordering and unless the particular method explicitly provides such guarantees.
atomicity.
Upon execution, a method with a Depth header will perform as much of Upon execution, a method with a Depth header will perform as much of
its assigned task as possible and then return a response specifying its assigned task as possible and then return a response specifying
what it was able to accomplish and what it failed to do. what it was able to accomplish and what it failed to do.
So, for example, an attempt to COPY a hierarchy may result in some So, for example, an attempt to COPY a hierarchy may result in some
of the members being copied and some not. of the members being copied and some not.
Any headers on a method with a Depth header MUST be applied to all Any headers on a method that has a defined interaction with the
resources in the scope of the method. For example, an If-Match Depth header MUST be applied to all resources in the scope of the
header will have its value applied against every resource in the method except where alternative behavior is explicitly defined. For
method's scope and will cause the method to fail if the header fails example, an If-Match header will have its value applied against
to match. every resource in the method's scope and will cause the method to
fail if the header fails to match.
If a resource, source or destination, within the scope of the method If a resource, source or destination, within the scope of the method
is locked in such a way as to prevent the successful execution of with a depth header is locked in such a way as to prevent the
the method, then the lock token for that resource MUST be submitted successful execution of the method, then the lock token for that
with the request in the Lock-Token request header. resource MUST be submitted with the request in the If request
header.
The Depth header only specifies the behavior of the method with The Depth header only specifies the behavior of the method with
regards to internal children. If a resource does not have internal regards to internal children. If a resource does not have internal
children then the Depth header is ignored. children then the Depth header MUST be ignored.
Please note, however, that it is always an error to submit a value Please note, however, that it is always an error to submit a value
for the Depth header that is not allowed by the method's definition. for the Depth header that is not allowed by the method's definition.
Thus submitting a "Depth: 1" on a COPY, even if the resource does Thus submitting a "Depth: 1" on a COPY, even if the resource does
not have internal members, MUST result in a 400 Bad Request. The not have internal members, will result in a 400 Bad Request. The
method should fail not because the resource doesn't have internal method should fail not because the resource doesn't have internal
members, but because of the illegal value in the header. members, but because of the illegal value in the header.
8.4 Destination Header 8.3 Destination Header
Destination = "Destination" ":" URI Destination = "Destination" ":" URI
The Destination header specifies a destination resource for methods The Destination header specifies a destination resource for methods
such as COPY and MOVE, which take two URIs as parameters. such as COPY and MOVE, which take two URIs as parameters.
8.5 If-None-State-Match 8.4 If Header
If-None-State-Match = "If-None-State-Match" ":" 1#Coded-URL If = "If" ":" ( 1*No-tag-list | 1*Tagged-list)
Coded-URL = "<" URI ">" No-tag-list = List
Tagged-list = Resource 1*List
Resource = Coded-url
List = "(" 1*(["Not"](State-token | "[" entity-tag "]")) ")"
State-token = Coded-url
Coded-url = "<" URI ">"
The If-None-State-Match header is intended to have similar The If header is intended to have similar functionality to the If-
functionality to the If-None-Match header defined in section 14.26 Match header defined in section 14.25 of [Fielding et al., 1997].
of [Fielding et al., 1997]. However the If-None-State-Match header However the If header is intended for use with any URI which
is intended for use with any URI which represents state information represents state information, referred to as a state token, about a
about a resource, referred to as a state token. A typical example resource as well as e-tags. A typical example of a state token is a
is a lock token. lock token, and lock tokens are the only state tokens defined in
this specification.
If any of the state tokens identifies the current state of the All DAV compliant resources MUST honor the If header.
resource, the server MUST NOT perform the requested method.
Instead, if the request method was GET, HEAD, or PROPFIND, the
server SHOULD respond with a 304 Not Modified response, including
the cache-related entity-header fields (particularly ETag) of the
current state of the resource. For all other request methods, the
server MUST respond with a status of 412 Precondition Failed.
If none of the state tokens identifies the current state of the The If header's purpose is to describe a series of state lists. If
resource, the server MAY perform the requested method. the state of the resource to which the header is applied does not
match any of the specified state lists then the request MUST fail
with a 412 Precondition Failed. If one of the described state lists
matches the state of the resource then the request may succeed.
If any of the tokens is not recognized, the method MUST fail with a 8.4.1 No-tag-list Production
412 Precondition Failed.
Note that the "AND" and "OR" keywords specified with the If-State- The No-tag-list production describes a series of state tokens and e-
Match header are intentionally not defined for If-None-State-Match, tags. If multiple No-tag-list productions are used then only one
because this functionality is not required. needs to match the state of the resource for the method to be
allowed to continue.
8.6 If-State-Match If a method, due to the presence of a Depth or Destination header,
is applied to multiple resources then the No-tag-list production
MUST be applied to each resource the method is applied to.
If-State-Match = "If-State-Match" ":" ("AND" | "OR") 1#Coded-URL For example:
The If-State-Match header is intended to have similar functionality If: (<locktoken:a-write-lock-token> ["I am an e-tag"]) (["I am
to the If-Match header defined in section 14.25 of [Fielding et al., another e-tag"])
1997]. However the If-State-Match header is intended for use with
any URI which represents state information about a resource. A
typical example is a lock token.
If the AND keyword is used and all of the state tokens identify the The previous header would require that any resources within the
state of the resource, then the server MAY perform the requested scope of the method must either be locked with the specified lock
method. If the OR keyword is used and any of the state tokens token and in the state identified by the "I am an e-tag" e-tag or in
identifies the current state of the resource, then the server MAY the state identified by the second e-tag "I am another e-tag". To
perform the requested method. If the keyword requirement for the put the matter more plainly one can think of the previous If header
keyword used is not met, the server MUST NOT perform the requested as being in the form (or (and <locktoken:a-write-lock-token> ["I am
method, and MUST return a 412 Precondition Failed response. an e-tag"]) (and ["I am another e-tag"])).
If any of the tokens is not recognized, the method MUST fail with a 8.4.2 Tagged-list Production
412 Precondition Failed.
8.7 Lock-Token Request Header The tagged-list production scopes a list production. That is, it
Lock-Token = "Lock-Token" ":" 1#Coded-URL specifies that the lists following the resource specification only
apply to the specified resource. The scope of the resource
production begins with the list production immediately following the
resource production and ends with the next resource production, if
any.
The Lock-Token request header, containing a lock token owned by the When the If header is applied to a particular resource, the Tagged-
requesting principal, is used by the principal to indicate that the list productions MUST be searched to determine if any of the listed
principal is aware of the existence of the lock specified by the resources match the operand resource(s) for the current method. If
lock token. none of the resource productions match the current resource then the
header MUST be ignored. If one of the resource productions does
match the name of the resource under consideration then the list
productions following the resource production MUST be applied to the
resource in the manner specified in the previous section.
If the following conditions are met: The same URI MUST NOT appear more than once in a resource production
in an If header.
1) The method is restricted by a lock type that requires the For example:
submission of a lock token, such as a write lock,
2) The user-agent has authenticated itself as a given principal,
3) The user-agent is submitting a method request to a resource on
which the principal owns a write lock,
Then: COPY /resource1 HTTP/1.1
Host: www.foo.bar
Destination: http://www.foo.bar/resource2
If: <http://www.foo.bar/resource1> (<locktoken:a-write-lock-token>
[W/"A weak e-tag"]) (["strong e-tag"])
<http://www.bar.bar/random>(["another strong e-tag"])
1) The method request MUST include a Lock-Token header with the lock In this example http://www.foo.bar/resource1 is being copied to
token, or, http://www.foo.bar/resource2. When the method is first applied to
2) The method MUST fail with a 409 Conflict status code. http://www.foo.bar/resource1, resource1 must be in the state
specified by "(<locktoken:a-write-lock-token> [W/"A weak e-tag"])
(["strong e-tag"])", that is, it either must be locked with a lock
token of "locktoken:a-write-lock-token" and have a weak entity tag
W/"A weak e-tag" or it must have a strong entity tag "strong e-tag".
If multiple resources are involved with a method, such as the MOVE That is the only success condition since the resource
method, then the lock tokens, if any, for all affected resources, http://www.bar.bar/random never has the method applied to it (the
MUST be included in the Lock-Token request header. only other resource listed in the If header) and
For example, Program A, used by user A, takes out a write lock on a http://www.foo.bar/resource2 is not listed in the If header.
resource. Program A then makes a number of PUT requests on the
locked resource. All the requests contain a Lock-Token request
header that includes the write lock token. Program B, also run by
User A, then proceeds to perform a PUT to the locked resource.
However, program B was not aware of the existence of the lock and so
does not include the appropriate Lock-Token request header. The
method is rejected even though principal A is authorized to perform
the PUT. Program B can, if it so chooses, now perform lock
discovery and obtain the lock token. Note that programs A and B can
perform GETs without using the Lock-Token header because the ability
to perform a GET is not affected by a write lock.
Having a lock token provides no special access rights. Anyone can 8.4.3 not Production
find out anyone else's lock token by performing lock discovery.
Locks are to be enforced based upon whatever authentication
mechanism is used by the server, not based on the secrecy of the
token values.
8.8 Lock-Token Response Header Every state token or e-tag is either current, and hence describes
the state of a resource, or is not current, and does not describe
the state of a resource. The boolean operation of matching a state
token or e-tag to the current state of a resource thus resolves to a
true or false value. The not production is used to reverse that
value. The scope of the not production is the state-token or
Lock-Token = "Lock-Token" ":" 1#Coded-URL entity-tag immediately following it.
If a resource is successfully locked then a Lock-Token header will If: (Not <locktoken:write1> <locktoken:write2>)
be returned containing the lock token that represents the lock.
If multiple lock-tokens are returned then they MUST all refer to the When submitted with a request, this If header requires that all
same lock. As the lock tokens all refer to the same lock a client operand resources must not be locked with locktoken:write1 and must
need only record one of them. be locked with locktoken:write2.
8.9 Overwrite Header 8.4.4 Matching Function
When performing If header processing, the definition of a matching
state token or entity tag is as follows.
Matching entity tag: Where the entity tag matches an entity tag
associated with that resource.
Matching state token: Where there is an exact match between the
state token in the If header and any state token on the resource.
8.4.5 If Header and Non-DAV Compliant Proxies
Non-DAV compliant proxies will not honor the If header, since they
will not understand the If header, and HTTP requires non-understood
headers to be ignored. When communicating with HTTP/1.1 proxies,
the "Cache-Control: no-cache" request header MUST be used so as to
prevent the proxy from improperly trying to service the request from
its cache. When dealing with HTTP/1.0 proxies the "Pragma: no-
cache" request header MUST be used for the same reason.
8.5 Lock-Token Request Header
Lock-Token = "Lock-Token" ":" Coded-URL
The Lock-Token request header is used with the UNLOCK method to
identify the lock to be removed. The lock token in the Lock-Token
request header MUST identify a lock that contains the resource
identified by Request-URI as a member.
8.6 Overwrite Header
Overwrite = "Overwrite" ":" ("T" | "F") Overwrite = "Overwrite" ":" ("T" | "F")
The Overwrite header specifies whether the server should overwrite The Overwrite header specifies whether the server should overwrite
the state of a non-null destination resource during a COPY or MOVE. the state of a non-null destination resource during a COPY or MOVE.
A value of "F" states that the server MUST NOT perform the COPY or A value of "F" states that the server must not perform the COPY or
MOVE operation if the state of the destination resource is non-null. MOVE operation if the state of the destination resource is non-null.
By default, the value of Overwrite is "T" and a client MAY omit this If the overwrite header is not included in a COPY or MOVE request
header from a request when its value is "T". While the Overwrite then the resource MUST treat the request as if it has an overwrite
header appears to duplicate the functionality of the If-Match: * header of value "T". While the Overwrite header appears to duplicate
header of HTTP/1.1, If-Match applies only to the Request-URI, and the functionality of the If-Match: * header of HTTP/1.1, If-Match
not to the Destination of a COPY or MOVE. applies only to the Request-URI, and not to the Destination of a
COPY or MOVE.
If a COPY or MOVE is not performed due to the value of the Overwrite If a COPY or MOVE is not performed due to the value of the Overwrite
header, the method MUST fail with a 409 Conflict status code. header, the method MUST fail with a 409 Conflict status code.
8.10 Status-URI Response Header All DAV compliant resources MUST support the Overwrite header.
The Status-URI response header MAY be used with the 102 Processing 8.7 Status-URI Response Header
The Status-URI response header may be used with the 102 Processing
status code to inform the client as to the status of a method. status code to inform the client as to the status of a method.
Status-URI = "Status-URI" ":" *(Status-Code "<" URI ">") ; Status- Status-URI = "Status-URI" ":" *(Status-Code "<" URI ">") ; Status-
Code is defined in 6.1.1 of [Fielding et al., 1997] Code is defined in 6.1.1 of [Fielding et al., 1997]
The URIs listed in the header are source resources which have been The URIs listed in the header are source resources which have been
affected by the outstanding method. The status code indicates the affected by the outstanding method. The status code indicates the
resolution of the method on the identified resource. So, for resolution of the method on the identified resource. So, for
example, if a MOVE method on a collection is outstanding and a 102 example, if a MOVE method on a collection is outstanding and a 102
"Processing" response with a Status-URI response header is returned, "Processing" response with a Status-URI response header is returned,
the included URIs will indicate resources that have had move the included URIs will indicate resources that have had move
attempted on them and what the result was. attempted on them and what the result was.
8.11 Timeout Header 8.8 Timeout Request Header
TimeOut = "Timeout" ":" 1#TimeType TimeOut = "Timeout" ":" 1#TimeType
TimeType = ("Second-" DAVTimeOutVal | "Infinite" | Other) TimeType = ("Second-" DAVTimeOutVal | "Infinite" | Other)
DAVTimeOutVal = 1*digit DAVTimeOutVal = 1*digit
Other = Extend field-value ; See section 4.2 of [Fielding et al., Other = Extend field-value ; See section 4.2 of [Fielding et al.,
1997] 1997]
Clients MAY include Timeout headers in their LOCK requests. Clients may include Timeout headers in their LOCK requests.
However, the server is not required to honor or even consider these However, the server is not required to honor or even consider these
requests. Clients MUST NOT submit a Timeout request header with any requests. Clients MUST NOT submit a Timeout request header with any
method other than a LOCK method. method other than a LOCK method.
A Timeout request header MUST contain at least one TimeType and MAY A Timeout request header MUST contain at least one TimeType and may
contain multiple TimeType entries. The purpose of listing multiple contain multiple TimeType entries. The purpose of listing multiple
TimeType entries is to indicate multiple different values and value TimeType entries is to indicate multiple different values and value
types that are acceptable to the client. The client lists the types that are acceptable to the client. The client lists the
TimeType entries in order of preference. TimeType entries in order of preference.
The Timeout response header MUST use a Second value, Infinite, or a Timeout response valuse MUST use a Second value, Infinite, or a
TimeType the client has indicated familiarity with. The server MAY TimeType the client has indicated familiarity with. The server may
assume a client is familiar with any TimeType submitted in a Timeout assume a client is familiar with any TimeType submitted in a Timeout
header. header.
The "Second" TimeType specifies the number of seconds that MUST The "Second" TimeType specifies the number of seconds that will
elapse between granting of the lock at the server, and the automatic elapse between granting of the lock at the server, and the automatic
removal of the lock. A server MUST not generate a timeout value for removal of the lock. The timeout value for timetype "Second" MUST
"Second" greater than 2^32-1. NOT be greater than 2^32-1.
The timeout counter SHOULD be restarted any time an owner of the The timeout counter SHOULD be restarted any time an owner of the
lock sends a method to any member of the lock, including unsupported lock sends a method to any member of the lock, including unsupported
methods, or methods which are unsuccessful. However the lock MUST methods, or methods which are unsuccessful. However the lock MUST
be refreshed if a refresh LOCK method is successfully received. be refreshed if a refresh LOCK method is successfully received.
If the timeout expires then the lock is lost. Specifically the If the timeout expires then the lock may be lost. Specifically, if
server SHOULD act as if an UNLOCK method was executed by the server the server wishes to harvest the lock upon time-out, the server
on the resource using the lock token of the timed-out lock, SHOULD act as if an UNLOCK method was executed by the server on the
performed with its override authority. Thus logs should be updated resource using the lock token of the timed-out lock, performed with
with the disposition of the lock, notifications should be sent, its override authority. Thus logs should be updated with the
etc., just as they would be for an UNLOCK request. disposition of the lock, notifications should be sent, etc., just as
they would be for an UNLOCK request.
Servers are advised to pay close attention to the values submitted Servers are advised to pay close attention to the values submitted
by clients, as they will be indicative of the type of activity the by clients, as they will be indicative of the type of activity the
client intends to perform. For example, an applet running in a client intends to perform. For example, an applet running in a
browser may need to lock a resource, but because of the instability browser may need to lock a resource, but because of the instability
of the environment within which the applet is running, the applet of the environment within which the applet is running, the applet
may be turned off without warning. As a result, the applet is may be turned off without warning. As a result, the applet is
likely to ask for a relatively small timeout value so that if the likely to ask for a relatively small timeout value so that if the
applet dies, the lock can be quickly harvested. However, a document applet dies, the lock can be quickly harvested. However, a document
management system is likely to ask for an extremely long timeout management system is likely to ask for an extremely long timeout
because its user may be planning on going off-line. because its user may be planning on going off-line.
A client MUST NOT assume that just because the time-out has expired
the lock has been lost.
9 Status Code Extensions to HTTP/1.1 9 Status Code Extensions to HTTP/1.1
The following status codes are added to those defined in HTTP/1.1 The following status codes are added to those defined in HTTP/1.1
[Fielding et al., 1997]. [Fielding et al., 1997].
9.1 102 Processing 9.1 102 Processing
Methods can potentially take a long period of time to process, Methods can potentially take a long period of time to process,
especially methods that support the Depth header. In such cases the especially methods that support the Depth header. In such cases the
client may time-out the connection while waiting for a response. To client may time-out the connection while waiting for a response. To
prevent this the server MAY return a 102 status code to indicate to prevent this the server may return a 102 status code to indicate to
the client that the server is still processing the method. the client that the server is still processing the method.
If a method is taking longer than 20 seconds (a reasonable, but If a method is taking longer than 20 seconds (a reasonable, but
arbitrary value) to process the server SHOULD return a 102 arbitrary value) to process the server SHOULD return a 102
"Processing" response. "Processing" response.
9.2 207 Multi-Status 9.2 207 Multi-Status
The response provides status for multiple independent operations. The response provides status for multiple independent operations.
9.3 422 Unprocessable Entity 9.3 422 Unprocessable Entity
The server understands the content type of the request entity, but The server understands the content type of the request entity, but
was unable to process the contained instructions. was unable to process the contained instructions.
9.4 423 Insufficient Space on Resource 9.4 423 Locked
The resource does not have sufficient space to record the state of The source or destination resource of a method is locked.
the resource after the execution of this method.
9.5 424 Method Failure 9.5 424 Method Failure
The method was not executed on a particular resource within its The method was not executed on a particular resource within its
scope because some part of the method's execution failed causing the scope because some part of the method's execution failed causing the
entire method to be aborted. For example, if a resource could not entire method to be aborted. For example, if a resource could not
be moved as part of a MOVE method, all the other resources would be moved as part of a MOVE method, all the other resources would
fail with a 424 Method Failure. fail with a 424 Method Failure.
9.6 425 Locked 9.6 425 Insufficient Space on Resource
The source or destination resource of a method is locked, and either The resource does not have sufficient space to record the state of
the request did not contain a valid Lock-Token header, or the lock the resource after the execution of this method.
token in the Lock-Token header identifies a lock held by another
principal.
10 Multi-Status Response 10 Multi-Status Response
The default 207 Multi-Status response body is a text/xml HTTP entity The default 207 Multi-Status response body is a text/xml HTTP entity
that contains a single XML element called multistatus, which that contains a single XML element called multistatus, which
contains a set of XML elements called response, one for each 200, contains a set of XML elements called response which contain 200,
300, 400, and 500 series status code generated during the method 300, 400, and 500 series status codes generated during the method
invocation. 100 series status codes MUST NOT be recorded in a invocation. 100 series status codes SHOULD NOT be recorded in a
response XML element. response XML element.
11 XML Element Definitions 11 XML Element Definitions
In the section below, the final line of each section gives the In the section below, the final line of each section gives the
element type declaration using the format defined in [Bray, Paoli, element type declaration using the format defined in [Bray, Paoli,
Sperberg-McQueen, 1998]. The "Value" field, where present, specifies Sperberg-McQueen, 1998]. The "Value" field, where present, specifies
futher restrictions on the allowable contents of the XML element futher restrictions on the allowable contents of the XML element
using BNF (i.e., to further restrict the values of a PCDATA using BNF (i.e., to further restrict the values of a PCDATA
element). element).
11.1 activelock XML Element 11.1 activelock XML Element
Name: activelock Name: activelock
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Describes a lock on a resource. Purpose: Describes a lock on a resource.
<!ELEMENT activelock (locktype, lockscope, depth?, owner, timeout, <!ELEMENT activelock (lockscope, locktype, depth, owner?, timeout?,
locktoken) > locktoken?) >
11.1.1 depth XML Element 11.1.1 depth XML Element
Name: depth Name: depth
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: The value of the depth header used to create a lock. Purpose: The value of the depth header used to create a lock.
Description: If this element is not included in a lockinfo element
then the client MUST assume that the lock is of depth 0.
Value: "0" | "infinity" Value: "0" | "infinity"
<!ELEMENT depth (#PCDATA) > <!ELEMENT depth (#PCDATA) >
11.1.2 locktoken XML Element 11.1.2 locktoken XML Element
Name: locktoken Name: locktoken
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: The lock token associated with a lock. Purpose: The lock token associated with a lock.
Description: The href contains an opaque lock token URI (i.e., the Description: The href contains one or more opaque lock token URIs
OpaqueLockToken-URI production in Section 4.4). which all refer to the same lock (i.e., the OpaqueLockToken-URI
production in section 5.4).
<!ELEMENT locktoken (href) > <!ELEMENT locktoken (href*) >
11.1.3 timeout XML Element 11.1.3 timeout XML Element
Name: timeout Name: timeout
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: The timeout associated with a lock Purpose: The timeout associated with a lock
Value: TimeType Value: TimeType ;Defined in section 8.8
<!ELEMENT timeout (#PCDATA) > <!ELEMENT timeout (#PCDATA) >
11.2 collection XML Element 11.2 collection XML Element
Name: collection Name: collection
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Identifies the associated resource as a collection. The Purpose: Identifies the associated resource as a collection. The
resourcetype property of a collection resource MUST have this value. resourcetype property of a collection resource MUST have this value.
<!ELEMENT collection EMPTY > <!ELEMENT collection EMPTY >
11.3 href XML Element 11.3 href XML Element
Name: href Name: href
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Identifies the content of the element as a URI. Purpose: Identifies the content of the element as a URI.
Value: URI ; See section 3.2.1 of [Fielding et al., 1997] Value: URI ; See section 3.2.1 of [Fielding et al., 1997]
<!ELEMENT href (#PCDATA)> <!ELEMENT href (#PCDATA)>
11.4 link XML Element 11.4 link XML Element
Name: link Name: link
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Identifies the property as a link and contains the Purpose: Identifies the property as a link and contains the
source and destination of that link. source and destination of that link.
Description: The link XML element is used to provide the sources and Description: The link XML element is used to provide the sources and
destinations of a link. The name of the property containing the destinations of a link. The name of the property containing the
link XML element provides the type of the link. Link is a multi- link XML element provides the type of the link. Link is a multi-
valued element, so multiple links may be used together to indicate valued element, so multiple links may be used together to indicate
multiple links with the same type. multiple links with the same type. The values in the href XML
elements inside the src and dst XML elements of the link XML element
MUST NOT be rejected if they point to resources which do not exist.
<!ELEMENT link (src+, dst+) > <!ELEMENT link (src+, dst+) >
11.4.1 dst XML Element 11.4.1 dst XML Element
Name: dst Name: dst
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Indicates the destination of a link Purpose: Indicates the destination of a link
Value: URI Value: URI
<!ELEMENT dst (#PCDATA) > <!ELEMENT dst (#PCDATA) >
11.4.2 src XML Element 11.4.2 src XML Element
Name: src Name: src
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Indicates the source of a link. Purpose: Indicates the source of a link.
Value: URI Value: URI
<!ELEMENT src (#PCDATA) > <!ELEMENT src (#PCDATA) >
11.5 lockentry XML Element 11.5 lockentry XML Element
Name: lockentry Name: lockentry
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Defines the types of locks that can be used with the Purpose: Defines the types of locks that can be used with the
resource. resource.
<!ELEMENT lockentry (lockscope, locktype) > <!ELEMENT lockentry (lockscope, locktype) >
11.6 lockinfo XML Element 11.6 lockinfo XML Element
Name: lockinfo Name: lockinfo
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: The lockinfo XML element is used with a LOCK method to Purpose: The lockinfo XML element is used with a LOCK method to
specify the type of lock the client wishes to have created. specify the type of lock the client wishes to have created.
<!ELEMENT lockinfo (lockscope, locktype, owner?) > <!ELEMENT lockinfo (lockscope, locktype, owner?) >
11.7 lockscope XML Element 11.7 lockscope XML Element
Name: lockscope Name: lockscope
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Specifies whether a lock is an exclusive lock, or a Purpose: Specifies whether a lock is an exclusive lock, or a
shared lock. shared lock.
<!ELEMENT lockscope (exclusive | shared) > <!ELEMENT lockscope (exclusive | shared) >
11.7.1 exclusive XML Element 11.7.1 exclusive XML Element
Name: exclusive Name: exclusive
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Specifies an exclusive lock Purpose: Specifies an exclusive lock
<!ELEMENT exclusive EMPTY > <!ELEMENT exclusive EMPTY >
11.7.2 shared XML Element 11.7.2 shared XML Element
Name: shared Name: shared
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Specifies a shared lock Purpose: Specifies a shared lock
<!ELEMENT shared EMPTY > <!ELEMENT shared EMPTY >
11.8 locktype XML Element 11.8 locktype XML Element
Name: locktype Name: locktype
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Specifies the access type of a lock. At present, this Purpose: Specifies the access type of a lock. At present, this
specification only defines one lock type, the write lock. specification only defines one lock type, the write lock.
<!ELEMENT locktype (write) > <!ELEMENT locktype (write) >
11.8.1 write XML Element 11.8.1 write XML Element
Name: write Name: write
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Specifies a write lock. Purpose: Specifies a write lock.
<!ELEMENT write EMPTY > <!ELEMENT write EMPTY >
11.9 multistatus XML Element 11.9 multistatus XML Element
Name: multistatus Name: multistatus
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Contains multiple response messages. Purpose: Contains multiple response messages.
Description: The responsedescription at the top level is used to Description: The responsedescription at the top level is used to
provide a general message describing the overarching nature of the provide a general message describing the overarching nature of the
response. If this value is available an application MAY use it response. If this value is available an application may use it
instead of presenting the individual response descriptions contained instead of presenting the individual response descriptions contained
within the responses. within the responses.
<!ELEMENT multistatus (response+, responsedescription?) > <!ELEMENT multistatus (response+, responsedescription?) >
11.9.1 response XML Element 11.9.1 response XML Element
Name: response Name: response
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Holds a single response describing the effect of a Purpose: Holds a single response describing the effect of a
method on resource and/or its properties. method on resource and/or its properties.
Description: A particular href MUST NOT appear more than once as the Description: A particular href MUST NOT appear more than once as the
child of a response XML element under a multistatus XML element. child of a response XML element under a multistatus XML element.
This requirement is necessary in order to keep processing costs for This requirement is necessary in order to keep processing costs for
a response to linear time. Essentially, this prevents having to a response to linear time. Essentially, this prevents having to
search in order to group together all the responses by href. There search in order to group together all the responses by href. There
are, however, no requirements regarding ordering based on href are, however, no requirements regarding ordering based on href
values. values.
<!ELEMENT response (href, ((href*, status)|(propstat+)), <!ELEMENT response (href, ((href*, status)|(propstat+)),
responsedescription?) > responsedescription?) >
11.9.1.1 propstat XML Element 11.9.1.1 propstat XML Element
Name: propstat Name: propstat
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Groups together a prop and status element that is Purpose: Groups together a prop and status element that is
associated with a particular href element. associated with a particular href element.
Description: Prop MUST contain one or more empty XML elements Description: The propstat XML element MUST contain one or more empty
representing the names of properties. Multiple properties may be prop XML elements representing the names of properties. Multiple
included if the same response applies to them all. properties may be included if the same response applies to them all.
<!ELEMENT propstat (prop, status) > <!ELEMENT propstat (prop*, status) >
11.9.1.2 status XML Element 11.9.1.2 status XML Element
Name: status Name: status
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Holds a single HTTP status-line Purpose: Holds a single HTTP status-line
Value: status-line ;status-line defined in [Fielding et al., Value: status-line ;status-line defined in [Fielding et al.,
1997] 1997]
<!ELEMENT status (#PCDATA) > <!ELEMENT status (#PCDATA) >
11.9.2 responsedescription XML Element 11.9.2 responsedescription XML Element
Name: responsedescription Name: responsedescription
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Contains a message that can be displayed to the user Purpose: Contains a message that can be displayed to the user
explaining the nature of the response. explaining the nature of the response.
Description: This XML element provides information suitable to be Description: This XML element provides information suitable to be
presented to a user. presented to a user.
<!ELEMENT responsedescription (#PCDATA) > <!ELEMENT responsedescription (#PCDATA) >
11.10 owner XML Element 11.10 owner XML Element
Name: owner Name: owner
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Provides information about the principal taking out a Purpose: Provides information about the principal taking out a
lock. lock.
Description: The owner XML element provides information sufficient Description: The owner XML element provides information sufficient
for either directly contacting a principal (such as a telephone for either directly contacting a principal (such as a telephone
number or Email URI), or for discovering the principal (such as the number or Email URI), or for discovering the principal (such as the
URL of a homepage) who owns a lock. URL of a homepage) who owns a lock.
<!ELEMENT owner (#PCDATA, ANY)* > <!ELEMENT owner ANY>
11.11 prop XML element 11.11 prop XML element
Name: prop Name: prop
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Contains properties related to a resource. Purpose: Contains properties related to a resource.
Description: The prop XML element is a generic container for Description: The prop XML element is a generic container for
properties defined on resources. All elements inside prop MUST properties defined on resources. All elements inside a prop XML
define properties related to the resource. No other elements may be element MUST define properties related to the resource. No other
used inside of a prop element. elements may be used inside of a prop element.
<!ELEMENT prop ANY> <!ELEMENT prop ANY>
11.12 propertybehavior XML element 11.12 propertybehavior XML element
Name: propertybehavior Name: propertybehavior
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Specifies how properties are handled during a COPY or Purpose: Specifies how properties are handled during a COPY or
MOVE. MOVE.
Description: The propertybehavior XML element specifies how Description: The propertybehavior XML element specifies how
properties are handled during a COPY or MOVE. If this XML element properties are handled during a COPY or MOVE. If this XML element
is not included in the request body then the server is expected to is not included in the request body then the server is expected to
act as defined by the default property handling behavior of the act as defined by the default property handling behavior of the
associated method. associated method. All WebDAV compliant resources MUST support the
propertybehavior XML element.
<!ELEMENT propertybehavior (omit | keepalive) > <!ELEMENT propertybehavior (omit | keepalive) >
11.12.1 keepalive XML element 11.12.1 keepalive XML element
Name: keepalive Name: keepalive
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Specifies requirements for the copying/moving of live Purpose: Specifies requirements for the copying/moving of live
properties. properties.
Description: If a list of URIs is included as the value of keepalive Description: If a list of URIs is included as the value of keepalive
then the named properties MUST be "live" after they are copied then the named properties MUST be "live" after they are copied
(moved) to the destination resource of a COPY (or MOVE). If the (moved) to the destination resource of a COPY (or MOVE). If the
value "*" is given for the keepalive XML element, this designates value "*" is given for the keepalive XML element, this designates
that all live properties on the source resource MUST be live on the that all live properties on the source resource MUST be live on the
destination. destination. If the requirements specified by the keepalive element
can not be honored then the method MUST fail with a 412 Precondition
Failed. All DAV compliant resources MUST support the keepalive XML
element for use with the COPY and MOVE methods.
Value: "*" ; #PCDATA value can only be "*" Value: "*" ; #PCDATA value can only be "*"
<!ELEMENT keepalive (#PCDATA | href+) > <!ELEMENT keepalive (#PCDATA | href+) >
11.12.2 omit XML element 11.12.2 omit XML element
Name: omit Name: omit
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Indicates that the associated method MAY succeed even if Purpose: The omit XML element instructs the server that it should
the server is not able to copy/move every property on the source use best effort to copy properties but a failure to copy a property
resource, even in a dead form. MUST NOT cause the method to fail.
Description: The default behavior for a COPY or MOVE is to copy/move Description: The default behavior for a COPY or MOVE is to copy/move
all properties or fail the method. In certain circumstances, such all properties or fail the method. In certain circumstances, such
as when a server copies a resource over another protocol such as as when a server copies a resource over another protocol such as
FTP, it may not be possible to copy/move the properties associated FTP, it may not be possible to copy/move the properties associated
with the resource. Thus any attempt to copy/move over FTP would with the resource. Thus any attempt to copy/move over FTP would
always have to fail because properties could not be moved over, even always have to fail because properties could not be moved over, even
as dead properties. The omit XML element instructs the server that as dead properties. All DAV compliant resources MUST support the
it should use best effort to copy properties but a failure to copy a omit XML element on COPY/MOVE methods.
property should not cause the method to fail.
<!ELEMENT omit EMPTY > <!ELEMENT omit EMPTY >
11.13 propertyupdate XML element 11.13 propertyupdate XML element
Name: propertyupdate Name: propertyupdate
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Contains a request to alter the properties on a Purpose: Contains a request to alter the properties on a
resource. resource.
Description: This XML element is a container for the information Description: This XML element is a container for the information
required to modify the properties on the resource. This XML element required to modify the properties on the resource. This XML element
is multi-valued. is multi-valued.
<!ELEMENT propertyupdate (remove | set)+ > <!ELEMENT propertyupdate (remove | set)+ >
11.13.1 remove XML element 11.13.1 remove XML element
Name: remove Name: remove
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Lists the DAV properties to be removed from a resource. Purpose: Lists the DAV properties to be removed from a resource.
Description: Remove instructs that the properties specified in prop Description: Remove instructs that the properties specified in prop
should be removed. Specifying the removal of a property that does should be removed. Specifying the removal of a property that does
not exist is not an error. All the XML elements in prop MUST be not exist is not an error. All the XML elements in a prop XML
empty, as only the names of properties to be removed are required. element inside of a remove XML element MUST be empty, as only the
names of properties to be removed are required.
<!ELEMENT remove (prop) > <!ELEMENT remove (prop) >
11.13.2 set XML element 11.13.2 set XML element
Name: set Name: set
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Lists the DAV property values to be set for a resource. Purpose: Lists the DAV property values to be set for a resource.
Value: prop Description: The set XML element MUST contain only a prop XML
Description: This XML element MUST contain only a prop XML element. element. The elements contained by the prop XML element inside the
The elements contained by prop specify the name and value of set XML element MUST specify the name and value of properties that
properties that are set on the Request-URI. If a property already are set on the Request-URI. If a property already exists then its
exists then its value is replaced. value is replaced.
<!ELEMENT set (prop) > <!ELEMENT set (prop) >
11.14 propfind XML Element 11.14 propfind XML Element
Name: propfind Name: propfind
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Specifies the properties to be returned from a PROPFIND Purpose: Specifies the properties to be returned from a PROPFIND
method. Two special elements are specified for use with propfind, method. Two special elements are specified for use with propfind,
allprop and propname. allprop and propname. If prop is used inside propfind it MUST only
contain property names, not values.
<!ELEMENT propfind (allprop | propname | href+) > <!ELEMENT propfind (allprop | propname | prop) >
11.14.1 allprop XML Element 11.14.1 allprop XML Element
Name: allprop Name: allprop
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: The allprop XML element specifies that all property Purpose: The allprop XML element specifies that all property
names and values on the resource are to be returned. names and values on the resource are to be returned.
<!ELEMENT allprop EMPTY > <!ELEMENT allprop EMPTY >
11.14.2 propname XML Element 11.14.2 propname XML Element
Name: propname Name: propname
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: the propname XML element specifies that only a list of Purpose: The propname XML element specifies that only a list of
property names on the resource is to be returned. property names on the resource is to be returned.
<!ELEMENT propname EMPTY > <!ELEMENT propname EMPTY >
12 DAV Properties 12 DAV Properties
For DAV properties, the name of the property is also the same as the For DAV properties, the name of the property is also the same as the
name of the XML element which contains its value. In the section name of the XML element that contains its value. In the section
below, the final line of each section gives the element type below, the final line of each section gives the element type
declaration using the format defined in [Bray, Paoli, Sperberg- declaration using the format defined in [Bray, Paoli, Sperberg-
McQueen, 1998]. The "Value" field, where present, specifies futher McQueen, 1998]. The "Value" field, where present, specifies futher
restrictions on the allowable contents of the XML element using BNF restrictions on the allowable contents of the XML element using BNF
(i.e., to further restrict the values of a PCDATA element). (i.e., to further restrict the values of a PCDATA element).
12.1 creationdate Property 12.1 creationdate Property
Name: creationdate Name: creationdate
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Records the time and date the resource was created. Purpose: Records the time and date the resource was created.
Value: ;The time and date MUST be given in ISO 8601 format Value: date-time ; See Appendix 2
defined in Appendix 2 Description: The creationdate property should be defined on all DAV
Description: This property SHOULD be defined on all DAV compliant compliant resources. If present, it contains a timestamp of the
resources. If present, it contains a timestamp of the moment when moment when the resource was created (i.e., the moment it had non-
the resource was created (i.e., the moment it had non-null state). null state).
<!ELEMENT creationdate (#PCDATA) > <!ELEMENT creationdate (#PCDATA) >
12.2 displayname Property 12.2 displayname Property
Name: displayname Name: displayname
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Provies a name for the resource that is suitable for Purpose: Provides a name for the resource that is suitable for
presentation to a user. presentation to a user.
Description: This property SHOULD be defined on all DAV compliant Description: The displayname property should be defined on all DAV
resources. If present, the property contains a description of the compliant resources. If present, the property contains a
resource that is suitable for presentation to a user. description of the resource that is suitable for presentation to a
user.
<!ELEMENT displayname (#PCDATA) > <!ELEMENT displayname (#PCDATA) >
12.3 externalmembers Property 12.3 getcontentlanguage Property
Name: externalmembers
Namespace: http://www.iana.org/standards/dav/
Purpose: Provides the list of external members defined on the
resource.
Description: This property MUST be defined on any DAV compliant
resource with external members. If defined it MUST contain the full
list of external members. Resources MAY make this property read-
only, thus only allowing its value to be altered using the
ADDREF/DELREF methods.
<!ELEMENT externalmembers (href*) >
12.4 getcontentlanguage Property
Name: getcontentlanguage Name: getcontentlanguage
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Contains the Content-Language header returned by a GET Purpose: Contains the Content-Language header returned by a GET
without accept headers without accept headers
Description: This property MUST be defined on any DAV compliant Description: The getcontentlanguage property MUST be defined on any
resource which supports GET, with the exception that if no Content- DAV compliant resource that returns the Content-Language header on a
Language header is available, this property MUST NOT exist. GET.
Value: language-tag ;language-tag is defined in section 14.13 Value: language-tag ;language-tag is defined in section 14.13
of [Fielding et al., 1997] of [Fielding et al., 1997]
<!ELEMENT getcontentlanguage (#PCDATA) > <!ELEMENT getcontentlanguage (#PCDATA) >
12.5 getcontentlength Property 12.4 getcontentlength Property
Name: getcontentlength Name: getcontentlength
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Contains the Content-Length header returned by a GET Purpose: Contains the Content-Length header returned by a GET
without accept headers. If no Content-Length header is available, without accept headers.
this property MUST NOT exist. Description: The getcontentlength property MUST be defined on any
Description: This property MUST be defined on any DAV compliant DAV compliant resource that returns the Content-Length header in
resource which returns the Content-Length header in response to a response to a GET.
GET.
Value: content-length ; see section 14.14 of [Fielding et al., Value: content-length ; see section 14.14 of [Fielding et al.,
1997] 1997]
<!ELEMENT getcontentlength (#PCDATA) > <!ELEMENT getcontentlength (#PCDATA) >
12.6 getcontenttype Property 12.5 getcontenttype Property
Name: getcontenttype Name: getcontenttype
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Contains the Content-Type header returned by a GET Purpose: Contains the Content-Type header returned by a GET
without accept headers. If no Content-Type header is available, without accept headers.
this property MUST NOT exist. Description: This getcontenttype property MUST be defined on any DAV
Description: This property MUST be defined on any DAV compliant compliant resource that returns the Content-Type header in response
resource which returns the Content-Type header in response to a GET. to a GET.
Value: media-type ; defined in Section 3.7 of [Fielding et Value: media-type ; defined in section 3.7 of [Fielding et
al., 1997] al., 1997]
<!ELEMENT getcontenttype (#PCDATA) > <!ELEMENT getcontenttype (#PCDATA) >
12.7 getetag Property 12.6 getetag Property
Name: getetag Name: getetag
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Contains the ETag header returned by a GET without Purpose: Contains the ETag header returned by a GET without
accept headers. accept headers.
Description: Note that the ETag on a resource may reflect changes in Description: Note that the ETag on a resource may reflect changes in
any part of the state of the resource, not necessarily just a change any part of the state of the resource, not necessarily just a change
to the response to the GET method. For example, a change to a to the response to the GET method. For example, a change to a
resource's access permissions may cause the ETag to change. This resource's access permissions may cause the ETag to change. The
property MUST be defined on any DAV compliant resource which returns getetag property MUST be defined on any DAV compliant resource that
the Etag header in response to a GET, except for the case if no ETag returns the Etag header in response to a GET.
header is returned, this property MUST NOT exist. Value: entity-tag ; defined in section 3.11 of [Fielding et
Value: entity-tag ; defined in Section 3.11 of [Fielding et
al., 1997] al., 1997]
<!ELEMENT getetag (#PCDATA) > <!ELEMENT getetag (#PCDATA) >
12.8 getlastmodified Property 12.7 getlastmodified Property
Name: getlastmodified Name: getlastmodified
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Contains the Last-Modified header returned by a GET Purpose: Contains the Last-Modified header returned by a GET
method without accept headers. method without accept headers.
Description: Note that the last-modified date on a resource may Description: Note that the last-modified date on a resource may
reflect changes in any part of the state of the resource, not reflect changes in any part of the state of the resource, not
necessarily just a change to the response to the GET method. For necessarily just a change to the response to the GET method. For
example, a change in a property may cause the last-modified date to example, a change in a property may cause the last-modified date to
change. This property MUST be defined on any DAV compliant resource change. The getlastmodified property MUST be defined on any DAV
which returns the Last-Modified header in response to a GET, except compliant resource that returns the Last-Modified header in response
for the case if no Last-Modified header is returned, this property to a GET.
MUST NOT exist. Value: HTTP-date ; defined in section 3.3.1 of [Fielding et
Value: HTTP-date ; defined in Section 3.3.1 of [Fielding et
al., 1997] al., 1997]
<!ELEMENT getlastmodified (#PCDATA) > <!ELEMENT getlastmodified (#PCDATA) >
12.9 lockdiscovery Property 12.8 lockdiscovery Property
Name: lockdiscovery Name: lockdiscovery
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Describes the active locks on a resource Purpose: Describes the active locks on a resource
Description: The lockdiscovery property returns a listing of who has Description: The lockdiscovery property returns a listing of who has
a lock, what type of lock he has, the timeout type and the time a lock, what type of lock he has, the timeout type and the time
remaining on the timeout, and the associated lock token. The server remaining on the timeout, and the associated lock token. The server
is free to withhold any or all of this information if the requesting is free to withhold any or all of this information if the requesting
principal does not have sufficient access rights to see the principal does not have sufficient access rights to see the
requested data. A server which supports locks MUST provide the requested data.
lockdiscovery property on any resource with locks on it.
<!ELEMENT lockdiscovery (activelock)* > <!ELEMENT lockdiscovery (activelock)* >
12.9.1 Example 12.8.1 Example
>>Request >>Request
PROPFIND /container/ HTTP/1.1 PROPFIND /container/ HTTP/1.1
Host: www.foo.bar Host: www.foo.bar
Content-Length: xxxx Content-Length: xxxx
Content-Type: text/xml Content-Type: text/xml
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href="http://www.iana.org/standards/dav/" as="D"?> <?xml:namespace name="DAV:" as="D"?>
<D:propfind> <D:propfind>
<D:prop><lockdiscovery/></D:prop> <D:prop><D:lockdiscovery/></D:prop>
</D:propfind> </D:propfind>
>>Response >>Response
HTTP/1.1 207 Multi-Status HTTP/1.1 207 Multi-Status
Content-Type: text/xml Content-Type: text/xml
Content-Length: xxxxx Content-Length: xxxxx
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href ="http://www.iana.org/standards/dav/" as="D"?> <?xml:namespace name="DAV:" as="D"?>
<D:multistatus> <D:multistatus>
<D:response> <D:response>
<D:href>http://www.foo.bar/container/</D:href>
<D:propstat> <D:propstat>
<D:prop> <D:prop>
<D:lockdiscovery> <D:lockdiscovery>
<D:activelock> <D:activelock>
<D:locktype>write</D:locktype> <D:locktype><D:write/></D:locktype>
<D:lockscope>exclusive</D:lockscope> <D:lockscope><D:exclusive/></D:lockscope>
<D:Depth>0</D:Depth> <D:depth>0</D:depth>
<D:owner>Jane Smith</D:owner> <D:owner>Jane Smith</D:owner>
<D:timeout>Infinite</D:timeout> <D:timeout>Infinite</D:timeout>
<D:locktoken> <D:locktoken>
<D:href> <D:href>
opaquelocktoken:f81de2ad-7f3d-a1b2-4f3c-00a0c91a9d76 opaquelocktoken:f81de2ad-7f3d-a1b2-4f3c-00a0c91a9d76
</D:href> </D:href>
</D:locktoken> </D:locktoken>
</D:activelock> </D:activelock>
</D:lockdiscovery> </D:lockdiscovery>
</D:prop> </D:prop>
<D:status>HTTP/1.1 200 OK</D:status> <D:status>HTTP/1.1 200 OK</D:status>
</D:propstat> </D:propstat>
</D:response> </D:response>
</D:multistatus> </D:multistatus>
This resource has a single exclusive write lock on it, with an This resource has a single exclusive write lock on it, with an
infinite timeout. Note that the Depth element could have been infinite timeout.
omitted as 0 is the default value of Depth.
12.10 resourcetype Property 12.9 resourcetype Property
Name: resourcetype Name: resourcetype
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: Specifies the nature of the resource. Purpose: Specifies the nature of the resource.
Description: This property MUST be defined on all DAV compliant Description: The resourcetype property MUST be defined on all DAV
resources. The default value is empty. compliant resources. The default value is empty.
<!ELEMENT resourcetype ANY > <!ELEMENT resourcetype ANY >
12.11 source Property 12.10 source Property
Name: source Name: source
Namespace: http://www.iana.org/standards/dav/link/ Namespace: DAV:
Purpose: The destination of the source link identifies the Purpose: The destination of the source link identifies the
resource that contains the unprocessed source of the link's source. resource that contains the unprocessed source of the link's source.
Description: The source of the link (src) is typically the URI of Description: The source of the link (src) is typically the URI of
the output resource on which the link is defined, and there is the output resource on which the link is defined, and there is
typically only one destination (dst) of the link, which is the URI typically only one destination (dst) of the link, which is the URI
where the unprocessed source of the resource may be accessed. When where the unprocessed source of the resource may be accessed. When
more than one link destination exists, this specification asserts no more than one link destination exists, this specification asserts no
policy on ordering. policy on ordering.
<!ELEMENT source (link)* > <!ELEMENT source (link)* >
12.11.1 Example 12.10.1 Example
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href="http://www.iana.org/standards/dav/" as="D"?> <?xml:namespace name="DAV:" as="D"?>
<?namespace href="http://www.foocorp.com/Project/" as="F"?> <?xml:namespace name="http://www.foocorp.com/Project/" as="F"?>
<D:prop> <D:prop>
<D:source> <D:source>
<D:link> <D:link>
<F:projfiles>Source</F:projfiles> <F:projfiles>Source</F:projfiles>
<D:src>http://foo.bar/program</D:src> <D:src>http://foo.bar/program</D:src>
<D:dst>http://foo.bar/src/main.c</D:dst> <D:dst>http://foo.bar/src/main.c</D:dst>
</D:link> </D:link>
<D:link> <D:link>
<F:projfiles>Library</F:projfiles> <F:projfiles>Library</F:projfiles>
<D:src>http://foo.bar/program</D:src> <D:src>http://foo.bar/program</D:src>
skipping to change at page 67, line 45 skipping to change at page 66, line 5
defined in this document, and one which is defined by the schema defined in this document, and one which is defined by the schema
http://www.foocorp.com/project/ (Source, Library, and Makefile). A http://www.foocorp.com/project/ (Source, Library, and Makefile). A
client which only implements the elements in the DAV spec will not client which only implements the elements in the DAV spec will not
understand the foocorp elements and will ignore them, thus seeing understand the foocorp elements and will ignore them, thus seeing
the expected source and destination links. An enhanced client may the expected source and destination links. An enhanced client may
know about the foocorp elements and be able to present the user with know about the foocorp elements and be able to present the user with
additional information about the links. This example demonstrates additional information about the links. This example demonstrates
the power of XML markup, allowing element values to be enhanced the power of XML markup, allowing element values to be enhanced
without breaking older clients. without breaking older clients.
12.12 supportedlock Property 12.11 supportedlock Property
Name: supportedlock Name: supportedlock
Namespace: http://www.iana.org/standards/dav/ Namespace: DAV:
Purpose: To provide a listing of the lock capabilities supported Purpose: To provide a listing of the lock capabilities supported
by the resource. by the resource.
Description: The supportedlock property of a resource returns a Description: The supportedlock property of a resource returns a
listing of the combinations of scope and access types which may be listing of the combinations of scope and access types which may be
specified in a lock request on the resource. Note that the actual specified in a lock request on the resource. Note that the actual
contents are themselves controlled by access controls so a server is contents are themselves controlled by access controls so a server is
not required to provide information the client is not authorized to not required to provide information the client is not authorized to
see. If supportedlock is available on "*" then it MUST define the
set of locks allowed on all resources on that server. see.
<!ELEMENT supportedlock (lockentry)* > <!ELEMENT supportedlock (lockentry)* >
12.12.1 Example 12.11.1 Example
>>Request >>Request
PROPFIND /container/ HTTP/1.1 PROPFIND /container/ HTTP/1.1
Host: www.foo.bar Host: www.foo.bar
Content-Length: xxxx Content-Length: xxxx
Content-Type: text/xml Content-Type: text/xml
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href="http://www.iana.org/standards/dav/" as="D"?> <?xml:namespace name="DAV:" as="D"?>
<D:propfind> <D:propfind>
<D:prop><supportedlock/></D:prop> <D:prop><D:supportedlock/></D:prop>
</D:propfind> </D:propfind>
>>Response >>Response
HTTP/1.1 207 Multi-Status HTTP/1.1 207 Multi-Status
Content-Type: text/xml Content-Type: text/xml
Content-Length: xxxxx Content-Length: xxxxx
<?xml version="1.0"?> <?xml version="1.0"?>
<?namespace href ="http://www.iana.org/standards/dav/" as="D"?> <?xml:namespace name="DAV:" as="D"?>
<D:multistatus> <D:multistatus>
<D:response> <D:response>
<D:href>http://www.foo.bar/container/</D:href>
<D:propstat> <D:propstat>
<D:prop> <D:prop>
<D:supportedlock> <D:supportedlock>
<D:LockEntry> <D:lockentry>
<D:locktype><D:Write/></D:locktype> <D:lockscope><D:exclusive/></D:lockscope>
<D:lockscope><D:Exclusive/></D:lockscope> <D:locktype><D:write/></D:locktype>
</D:LockEntry> </D:lockentry>
<D:LockEntry> <D:lockentry>
<D:locktype><D:Write/></D:locktype> <D:lockscope><D:shared/></D:lockscope>
<D:lockscope><D:Shared/></D:lockscope> <D:locktype><D:write/></D:locktype>
</D:LockEntry> </D:lockentry>
</D:supportedlock> </D:supportedlock>
</D:prop> </D:prop>
<D:status>HTTP/1.1 200 OK</D:status> <D:status>HTTP/1.1 200 OK</D:status>
</D:propstat> </D:propstat>
</D:response> </D:response>
</D:multistatus> </D:multistatus>
13 DAV Compliance Classes 13 DAV XML Processing Instructions
All DAV compliant resources MUST ignore any unknown XML element and
all its children encountered while processing a DAV method that uses
XML as its command language.
This restriction also applies to the processing, by clients, of DAV
property values where unknown XML elements SHOULD be ignored unless
the property's schema declares otherwise.
This restriction does not apply to setting dead DAV properties on
the server where the server MUST record unknown XML elements.
Additionally, this restriction does not apply to the use of XML
where XML happens to be the content type of the entity body, for
example, when used as the body of a PUT.
14 DAV Compliance Classes
A DAV compliant resource can choose from two classes of compliance. A DAV compliant resource can choose from two classes of compliance.
A client can discover the compliance classes of a resource by A client can discover the compliance classes of a resource by
executing OPTIONS on the resource, and examining the "DAV" header executing OPTIONS on the resource, and examining the "DAV" header
which is returned. which is returned.
Since this document describes extensions to the HTTP/1.1 protocol, Since this document describes extensions to the HTTP/1.1 protocol,
minimally all DAV compliant resources, clients, and proxies MUST be minimally all DAV compliant resources, clients, and proxies MUST be
compliant with [Fielding et al., 1997]. compliant with [Fielding et al., 1997].
Compliance classes are not necessarily sequential. A resource that Compliance classes are not necessarily sequential. A resource that
is class 2 compliant MUST also be class 1 compliant; but if is class 2 compliant must also be class 1 compliant; but if
additional compliance classes are defined later, a resource that is additional compliance classes are defined later, a resource that is
class 1, 2, and 4 compliant might not be class 3 compliant. class 1, 2, and 4 compliant might not be class 3 compliant. Also
note that identifiers other than numbers may be used as compliance
class identifiers.
13.1 Class 1 14.1 Class 1
A class 1 compliant resource MUST meet all "MUST" requirements in A class 1 compliant resource MUST meet all "MUST" requirements in
all sections of this document. all sections of this document.
Class 1 compliant resources MUST return, at minimum, the value "1" Class 1 compliant resources MUST return, at minimum, the value "1"
in the DAV header on all responses to the OPTIONS method. in the DAV header on all responses to the OPTIONS method.
13.2 Class 2 14.2 Class 2
A class 2 compliant resource MUST meet all class 1 requirements and A class 2 compliant resource MUST meet all class 1 requirements and
support the supportedlock property as well as the LOCK method. It support the LOCK method, the supportedlock property, the
MUST also support the lockdiscovery property, since Section 12.9 lockdiscovery property, the Time-Out response header and the Lock-
specifies that the LOCK method MUST also support the lockdiscovery Token request header. A class "2" compliant resource SHOULD also
property. support the Time-Out request header and the owner XML element.
Class 2 compliant resources MUST return, at minimum, the value "2" Class 2 compliant resources MUST return, at minimum, the values "1"
in the DAV header on all responses to the OPTIONS method. and "2" in the DAV header on all responses to the OPTIONS method.
14 Internationalization Considerations 15 Internationalization Considerations
In the realm of internationalization, this specification complies In the realm of internationalization, this specification complies
with the IETF Character Set Policy [Alvestrand, 1998]. In this with the IETF Character Set Policy [Alvestrand, 1998]. In this
specification, human-readable fields can be found either in the specification, human-readable fields can be found either in the
value of a property, or in an error message returned in a response value of a property, or in an error message returned in a response
entity body. In both cases, the human-readable content is encoded entity body. In both cases, the human-readable content is encoded
using XML, which has explicit provisions for character set tagging using XML, which has explicit provisions for character set tagging
and encoding, and requires that XML processors read XML elements and encoding, and requires that XML processors read XML elements
encoded using the UTF-8 and UCS-2 encodings of the ISO 10646 basic encoded, at minimum, using the UTF-8 [Yergeau, 1998] encoding of the
multilingual plane. Furthermore, XML contains provisions for ISO 10646 multilingual plane.
encoding XML elements using other encoding schemes, notable among
them UCS-4, which permits encoding of characters from any ISO 10646
character plane.
The default character set encoding for XML data in this
specification, and in general, is UTF-8. WebDAV compliant
applications MUST support the UTF-8 and UCS-2 character set
encodings for XML elements, and SHOULD support the UCS-4 encoding.
The XML character set encoding declaration for each supported
character set MUST also be supported, since it is by using this
encoding declaration that an XML processor determines the encoding
of an element.
XML also provides a language tagging capability for specifying the XML also provides a language tagging capability for specifying the
language of the contents of a particular XML element. XML uses language of the contents of a particular XML element. XML uses
either IANA registered language tags (see RFC 1766, [Alvestrand, either IANA registered language tags (see RFC 1766, [Alvestrand,
1995]) or ISO 639 language tags [ISO-639] in the "xml:lang" 1995]) or ISO 639 language tags [ISO-639] in the "xml:lang"
attribute of an XML element to identify the language its content and attribute of an XML element to identify the language of its content
attributes. and attributes.
WebDAV applications MUST support the character set tagging,
character set encoding, and the language tagging functionality of
the XML specification.
Names used within this specification fall into three categories: Names used within this specification fall into three categories:
names of protocol elements such as methods and headers, names of XML names of protocol elements such as methods and headers, names of XML
elements, and names of properties. Naming of protocol elements elements, and names of properties. Naming of protocol elements
follows the precedent of HTTP, using English names encoded in follows the precedent of HTTP, using English names encoded in
USASCII for methods and headers. Since these protocol elements are USASCII for methods and headers. Since these protocol elements are
not visible to users, and are in fact simply long token identifiers, not visible to users, and are in fact simply long token identifiers,
they do not need to support encoding in multiple character sets. they do not need to support encoding in multiple character sets.
Similarly, though the names of XML elements used in this Similarly, though the names of XML elements used in this
specification are English names encoded in UTF-8, these names are specification are English names encoded in UTF-8, these names are
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typical application will use a fixed set of properties, and will typical application will use a fixed set of properties, and will
provide a mapping from the property name URI to a human-readable provide a mapping from the property name URI to a human-readable
field when displaying the property name to a user. It is only in field when displaying the property name to a user. It is only in
the case where the set of properties is not known ahead of time that the case where the set of properties is not known ahead of time that
an application need display a property name URI to a user. We an application need display a property name URI to a user. We
recommend that applications provide human-readable property names recommend that applications provide human-readable property names
wherever feasible. wherever feasible.
For error reporting, we follow the convention of HTTP/1.1 status For error reporting, we follow the convention of HTTP/1.1 status
codes, including with each status code a short, English description codes, including with each status code a short, English description
of the code (e.g., 425 Locked). While the possibility exists that a of the code (e.g., 423 Locked). While the possibility exists that a
poorly crafted user agent would display this message to a user, poorly crafted user agent would display this message to a user,
internationalized applications will ignore this message, and display internationalized applications will ignore this message, and display
an appropriate message in the user's language and character set. an appropriate message in the user's language and character set.
Since interoperation of clients and servers does not require locale Since interoperation of clients and servers does not require locale
information, this specification does not specify any mechanism for information, this specification does not specify any mechanism for
transmission of this information. transmission of this information.
15 Security Considerations 16 Security Considerations
This section is provided to detail issues concerning security This section is provided to detail issues concerning security
implications of which WebDAV applications need to be aware. implications of which WebDAV applications need to be aware.
All of the security considerations of HTTP/1.1 also apply to WebDAV. All of the security considerations of HTTP/1.1 also apply to WebDAV.
In addition, the security risks inherent in remote authoring require In addition, the security risks inherent in remote authoring require
stronger authentication technology, and introduce several new stronger authentication technology, introduce several new privacy
privacy concerns, and may increase the hazards from poor server concerns, and may increase the hazards from poor server design.
design. These issues are detailed below. These issues are detailed below.
15.1 Authentication of Clients 16.1 Authentication of Clients
Due to their emphasis on authoring, WebDAV servers need to use Due to their emphasis on authoring, WebDAV servers need to use
authentication technology to protect not just access to a network authentication technology to protect not just access to a network
resource, but the integrity of the resource as well. Furthermore, resource, but the integrity of the resource as well. Furthermore,
the introduction of locking functionality requires support for the introduction of locking functionality requires support for
authentication. authentication.
A password sent in the clear over an insecure channel is an A password sent in the clear over an insecure channel is an
inadequate means for protecting the accessibility and integrity of a inadequate means for protecting the accessibility and integrity of a
resource as the password may be intercepted. Since Basic resource as the password may be intercepted. Since Basic
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transmission of a password, Basic authentication MUST NOT be used to transmission of a password, Basic authentication MUST NOT be used to
authenticate a WebDAV client to a server unless the connection is authenticate a WebDAV client to a server unless the connection is
secure. Furthermore, a WebDAV server MUST NOT send Basic secure. Furthermore, a WebDAV server MUST NOT send Basic
authentication credentials in a WWW-Authenticate header unless the authentication credentials in a WWW-Authenticate header unless the
connection is secure. Examples of secure connections include a connection is secure. Examples of secure connections include a
Transport Layer Security (TLS) connection, or a connection over a Transport Layer Security (TLS) connection, or a connection over a
network which is physically secure, for example, an isolated network network which is physically secure, for example, an isolated network
in a building with restricted access. in a building with restricted access.
WebDAV applications MUST support the Digest authentication scheme WebDAV applications MUST support the Digest authentication scheme
[Franks, et al., 1997]. Since Digest authentication verifies that [Franks et al., 1997]. Since Digest authentication verifies that
both parties to a communication know a shared secret, a password, both parties to a communication know a shared secret, a password,
without having to send that secret in the clear, Digest without having to send that secret in the clear, Digest
authentication avoids the security problems inherent in Basic authentication avoids the security problems inherent in Basic
authentication while providing a level of authentication which is authentication while providing a level of authentication which is
useful in a wide range of scenarios. useful in a wide range of scenarios.
15.2 Denial of Service 16.2 Denial of Service
Denial of service attacks are of special concern to WebDAV servers. Denial of service attacks are of special concern to WebDAV servers.
WebDAV plus HTTP enables denial of service attacks on every part of WebDAV plus HTTP enables denial of service attacks on every part of
a system's resources. a system's resources.
The underlying storage can be attacked by PUTting extremely large The underlying storage can be attacked by PUTting extremely large
files. files.
Asking for recursive operations on large collections can attack Asking for recursive operations on large collections can attack
processing time. processing time.
Making multiple pipelined requests on multiple connections can Making multiple pipelined requests on multiple connections can
attack network connections. attack network connections.
WebDAV servers need to be aware of the possibility of a denial of WebDAV servers need to be aware of the possibility of a denial of
service attack at all levels. service attack at all levels.
15.3 Security through Obscurity 16.3 Security through Obscurity
WebDAV provides, through the PROPFIND method, a mechanism for WebDAV provides, through the PROPFIND method, a mechanism for
listing the member resources of a collection. This greatly listing the member resources of a collection. This greatly
diminishes the effectiveness of security or privacy techniques which diminishes the effectiveness of security or privacy techniques that
rely only on the difficulty of discovering the names of network rely only on the difficulty of discovering the names of network
resources. Users of WebDAV servers are encouraged to use access resources. Users of WebDAV servers are encouraged to use access
control techniques to prevent unwanted access to resources, rather control techniques to prevent unwanted access to resources, rather
than depending on the relative obscurity of their resource names. than depending on the relative obscurity of their resource names.
15.4 Privacy Issues Connected to Locks 16.4 Privacy Issues Connected to Locks
When submitting a lock request a user agent may also submit an owner When submitting a lock request a user agent may also submit an owner
XML field giving contact information for the person taking out the XML field giving contact information for the person taking out the
lock (for those cases where a person, rather than a robot, is taking lock (for those cases where a person, rather than a robot, is taking
out the lock). This contact information is stored in a lockdiscovery out the lock). This contact information is stored in a lockdiscovery
property on the resource, and can be used by other collaborators to property on the resource, and can be used by other collaborators to
begin negotiation over access to the resource. However, in many begin negotiation over access to the resource. However, in many
cases this contact information can be very private, and should not cases this contact information can be very private, and should not
be widely disseminated. Servers SHOULD limit read access to the be widely disseminated. Servers SHOULD limit read access to the
lockdiscovery property as appropriate. Furthermore, user agents lockdiscovery property as appropriate. Furthermore, user agents
SHOULD provide control over whether contact information is sent at SHOULD provide control over whether contact information is sent at
all, and if contact information is sent, control over exactly what all, and if contact information is sent, control over exactly what
information is sent. information is sent.
15.5 Privacy Issues Connected to Properties 16.5 Privacy Issues Connected to Properties
Since property values are typically used to hold information such as Since property values are typically used to hold information such as
the author of a document, there is the possibility that privacy the author of a document, there is the possibility that privacy
concerns could arise stemming from widespread access to a resource's concerns could arise stemming from widespread access to a resource's
property data. To reduce the risk of inadvertent release of private property data. To reduce the risk of inadvertent release of private
information via properties, servers are encouraged to develop access information via properties, servers are encouraged to develop access
control mechanisms that separate read access to the resource body control mechanisms that separate read access to the resource body
and read access to the resource's properties. This allows a user to and read access to the resource's properties. This allows a user to
control the dissemination of their property data without overly control the dissemination of their property data without overly
restricting access to the resource's contents. restricting access to the resource's contents.
15.6 Reduction of Security due to Source Link 16.6 Reduction of Security due to Source Link
HTTP/1.1 warns against providing read access to script code because HTTP/1.1 warns against providing read access to script code because
it may contain sensitive information. Yet WebDAV, via its source it may contain sensitive information. Yet WebDAV, via its source
link facility, can potentially provide a URL for script resources so link facility, can potentially provide a URL for script resources so
they may be authored. For HTTP/1.1, a server could reasonably they may be authored. For HTTP/1.1, a server could reasonably
prevent access to source resources due to the predominance of read- prevent access to source resources due to the predominance of read-
only access. WebDAV, with its emphasis on authoring, encourages only access. WebDAV, with its emphasis on authoring, encourages
read and write access to source resources, and provides the source read and write access to source resources, and provides the source
link facility to identify the source. This reduces the security link facility to identify the source. This reduces the security
benefits of eliminating access to source resources. Users and benefits of eliminating access to source resources. Users and
administrators of WebDAV servers should be very cautious when administrators of WebDAV servers should be very cautious when
allowing remote authoring of scripts, limiting read and write access allowing remote authoring of scripts, limiting read and write access
to the source resources to authorized principals. to the source resources to authorized principals.
16 IANA Considerations 17 IANA Considerations
This document defines two namespaces, the namespace of property This document defines two namespaces, the namespace of property
names, and the namespace of WebDAV-specific XML elements used within names, and the namespace of WebDAV-specific XML elements used within
property values. property values.
URLs are used for both names, for several reasons. Assignment of a URLs are used for both names, for several reasons. Assignment of a
URL does not require a request to a central naming authority, and URL does not require a request to a central naming authority, and
hence allow WebDAV property names and XML elements to be quickly hence allow WebDAV property names and XML elements to be quickly
defined by any WebDAV user or application. URLs also provide a defined by any WebDAV user or application. URLs also provide a
unique address space, ensuring that the distributed users of WebDAV unique address space, ensuring that the distributed users of WebDAV
will not have collisions among the property names and XML elements will not have collisions among the property names and XML elements
they create. they create.
This specification defines a distinguished set of property names and This specification defines a distinguished set of property names and
XML elements which are understood by all WebDAV applications. The XML elements that are understood by all WebDAV applications. The
property names and XML elements in this specification are all property names and XML elements in this specification are all
derived from the base URL: http://www.iana.org/standards/dav/ by derived from the base URI DAV: by adding a suffix to this URI, for
adding a suffix to this URL, for example, example, DAV:creationdate for the "creationdate" property.
http://www.iana.org/standards/dav/creationdate for the
"creationdate" property.
To ensure correct interoperation of this specification, IANA MUST This specification also defines a URI scheme for the encoding of
reserve the URL namespace starting with lock tokens, the opaquelocktoken URI scheme described in section
http://www.iana.org/standards/dav/ for use by this specification, 5.4.
its revisions, and related WebDAV specifications.
17 Terminology To ensure correct interoperation based on this specification, IANA
must reserve the URI namespaces starting with "DAV:" and with
"opaquelocktoken:" for use by this specification, its revisions, and
related WebDAV specifications.
Collection - A resource that contains member resources. 18 Terminology
Member Resource - A resource contained by a collection. There are Collection - A resource that contains member resources and meets the
two types of member resources: external and internal. requirements in section 4 of this specification.
Member Resource - A resource contained by a collection.
Internal Member Resource - A member resource of a collection whose Internal Member Resource - A member resource of a collection whose
URI is relative to the URI of the collection. URI is relative to the URI of the collection.
External Member Resource - A member resource of a collection with an
absolute URI that is not relative to its parent's URI.
Property - A name/value pair that contains descriptive information Property - A name/value pair that contains descriptive information
about a resource. about a resource.
Live Property - A property whose semantics and syntax are enforced Live Property - A property whose semantics and syntax are enforced
by the server. For example, a live "content-length" property would by the server. For example, a live "content-length" property would
have its value, the length of the entity returned by a GET request, have its value, the length of the entity returned by a GET request,
automatically calculated by the server. automatically calculated by the server.
Dead Property - A property whose semantics and syntax are not Dead Property - A property whose semantics and syntax are not
enforced by the server. The server only records the value of a dead enforced by the server. The server only records the value of a dead
property; the client is responsible for maintaining the consistency property; the client is responsible for maintaining the consistency
of the syntax and semantics of a dead property. of the syntax and semantics of a dead property.
18 Copyright 19 Copyright
The following copyright notice is copied from RFC 2026 [Bradner, The following copyright notice is copied from RFC 2026 [Bradner,
1996], Section 10.4, and describes the applicable copyright for this 1996], section 10.4, and describes the applicable copyright for this
document. document.
Copyright (C) The Internet Society January 18, 1998. All Rights Copyright (C) The Internet Society March 6, 1998. All Rights
Reserved. Reserved.
This document and translations of it may be copied and furnished to This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph kind, provided that the above copyright notice and this paragraph
are included on all such copies and derivative works. However, this are included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other the copyright notice or references to the Internet Society or other
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The limited permissions granted above are perpetual and will not be The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assignees. revoked by the Internet Society or its successors or assignees.
This document and the information contained herein is provided on an This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
19 Intellectual Property 20 Intellectual Property
The following notice is copied from RFC 2026 [Bradner, 1996], The following notice is copied from RFC 2026 [Bradner, 1996],
Section 10.4, and describes the position of the IETF concerning section 10.4, and describes the position of the IETF concerning
intellectual property claims made against this document. intellectual property claims made against this document.
The IETF takes no position regarding the validity or scope of any The IETF takes no position regarding the validity or scope of any
intellectual property or other rights that might be claimed to intellectual property or other rights that might be claimed to
pertain to the implementation or use other technology described in pertain to the implementation or use other technology described in
this document or the extent to which any license under such rights this document or the extent to which any license under such rights
might or might not be available; neither does it represent that it might or might not be available; neither does it represent that it
has made any effort to identify any such rights. Information on the has made any effort to identify any such rights. Information on the
IETF's procedures with respect to rights in standards-track and IETF's procedures with respect to rights in standards-track and
standards-related documentation can be found in BCP-11. Copies of standards-related documentation can be found in BCP-11. Copies of
skipping to change at page 75, line 19 skipping to change at page 73, line 34
to obtain a general license or permission for the use of such to obtain a general license or permission for the use of such
proprietary rights by implementors or users of this specification proprietary rights by implementors or users of this specification
can be obtained from the IETF Secretariat. can be obtained from the IETF Secretariat.
The IETF invites any interested party to bring to its attention any The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary copyrights, patents or patent applications, or other proprietary
rights which may cover technology that may be required to practice rights which may cover technology that may be required to practice
this standard. Please address the information to the IETF Executive this standard. Please address the information to the IETF Executive
Director. Director.
20 Acknowledgements 21 Acknowledgements
A specification such as this thrives on piercing critical review and A specification such as this thrives on piercing critical review and
withers from apathetic neglect. The authors gratefully acknowledge withers from apathetic neglect. The authors gratefully acknowledge
the contributions of the following people, whose insights were so the contributions of the following people, whose insights were so
valuable at every stage of our work. valuable at every stage of our work.
Terry Allen, Harald Alvestrand, Alan Babich, Dylan Barrell, Bernard Terry Allen, Harald Alvestrand, Alan Babich, Sanford Barr, Dylan
Chester, Tim Berners-Lee, Dan Connolly, Jim Cunningham, Ron Daniel, Barrell, Bernard Chester, Tim Berners-Lee, Dan Connolly, Jim
Jr., Jim Davis, Keith Dawson, Mark Day, Brian Deen, Martin Duerst, Cunningham, Ron Daniel, Jr., Jim Davis, Keith Dawson, Mark Day,
David Durand, Lee Farrell, Chuck Fay, Roy Fielding, Mark Fisher, Brian Deen, Martin Duerst, David Durand, Lee Farrell, Chuck Fay, Roy
Alan Freier, George Florentine, Jim Gettys, Phill Hallam-Baker, Fielding, Mark Fisher, Alan Freier, George Florentine, Jim Gettys,
Dennis Hamilton, Steve Henning, Alex Hopmann, Andre van der Hoek, Phill Hallam-Baker, Dennis Hamilton, Steve Henning, Alex Hopmann,
Ben Laurie, Paul Leach, Ora Lassila, Karen MacArthur, Steven Martin, Andre van der Hoek, Ben Laurie, Paul Leach, Ora Lassila, Karen
Larry Masinter, Michael Mealling, Keith Moore, Henrik Nielsen, Kenji MacArthur, Steven Martin, Larry Masinter, Michael Mealling, Keith
Ota, Bob Parker, Glenn Peterson, Jon Radoff, Saveen Reddy, Henry Moore, Henrik Nielsen, Kenji Ota, Bob Parker, Glenn Peterson, Jon
Sanders, Christopher Seiwald, Judith Slein, Mike Spreitzer, Einar Radoff, Saveen Reddy, Henry Sanders, Christopher Seiwald, Judith
Stefferud, Ralph Swick, Kenji Takahashi, Richard N. Taylor, Robert Slein, Mike Spreitzer, Einar Stefferud, Ralph Swick, Kenji
Thau, John Turner, Sankar Virdhagriswaran, Fabio Vitali, Gregory Takahashi, Richard N. Taylor, Robert Thau, John Turner, Sankar
Woodhouse, and Lauren Wood. Virdhagriswaran, Fabio Vitali, Gregory Woodhouse, and Lauren Wood.
Two from this list deserve special mention. The contributions by Two from this list deserve special mention. The contributions by
Larry Masinter have been invaluable, both in helping the formation Larry Masinter have been invaluable, both in helping the formation
of the working group and in patiently coaching the authors along the of the working group and in patiently coaching the authors along the
way. In so many ways he has set high standards we have toiled to way. In so many ways he has set high standards we have toiled to
meet. The contributions of Judith Slein in clarifying the meet. The contributions of Judith Slein in clarifying the
requirements, and in patiently reviewing draft after draft, both requirements, and in patiently reviewing draft after draft, both
improved this specification and expanded our minds on document improved this specification and expanded our minds on document
management. management.
We would also like to thank John Turner for developing the XML DTD. We would also like to thank John Turner for developing the XML DTD.
21 References 22 References
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Languages." RFC 1766. Uninett. March, 1995. Languages." RFC 1766. Uninett. March, 1995.
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and Languages." RFC XXXX, BCP YY. Maxware. January, 1998. and Languages." RFC 2277, BCP 18. Uninett. January, 1998.
[Bradner, 1996] S. Bradner, "The Internet Standards Process - [Bradner, 1996] S. Bradner, "The Internet Standards Process -
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Requirement Levels." RFC 2119, BCP 14. Harvard University. March, Requirement Levels." RFC 2119, BCP 14. Harvard University. March,
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labels-961031.html. labels-961031.html.