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Network Working Group                                   J. Gregorio, Ed.
Internet-Draft                                           BitWorking, Inc
Expires: September 19, 2005                                R. Sayre, Ed.
                                               Boswijck Memex Consulting
                                                          March 18, 2005


                      The Atom Publishing Protocol
                   draft-ietf-atompub-protocol-03.txt

Status of this Memo

   This document is an Internet-Draft and is subject to all provisions
   of Section 3 of RFC 3667.  By submitting this Internet-Draft, each
   author represents that any applicable patent or other IPR claims of
   which he or she is aware have been or will be disclosed, and any of
   which he or she become aware will be disclosed, in accordance with
   RFC 3668.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as
   Internet-Drafts.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt.

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html.

   This Internet-Draft will expire on September 19, 2005.

Copyright Notice

   Copyright (C) The Internet Society (2005).

Abstract

   This memo presents a protocol for using XML (Extensible Markup
   Language) and HTTP (HyperText Transport Protocol) to edit content.

   The Atom Publishing Protocol is an application-level protocol for
   publishing and editing Web resources belonging to periodically



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   updated websites.  The protocol at its core is the HTTP transport of
   Atom-formatted representations.  The Atom format is documented in the
   Atom Syndication Format (draft-ietf-atompub-format-06.txt).

Editorial Note

   To provide feedback on this Internet-Draft, join the atom-syntax
   mailing list (http://www.imc.org/atom-syntax/index.html) [1].

Table of Contents

   1.   Introduction . . . . . . . . . . . . . . . . . . . . . . . .   4
     1.1  Notational Conventions . . . . . . . . . . . . . . . . . .   4
     1.2  Terminology  . . . . . . . . . . . . . . . . . . . . . . .   4
   2.   The Atom Publishing Protocol Model . . . . . . . . . . . . .   4
     2.1  Atom Collections . . . . . . . . . . . . . . . . . . . . .   4
       2.1.1  Usage  . . . . . . . . . . . . . . . . . . . . . . . .   5
       2.1.2  Client and Server Interaction  . . . . . . . . . . . .   5
   3.   Functional Specification . . . . . . . . . . . . . . . . . .   5
     3.1  Collections  . . . . . . . . . . . . . . . . . . . . . . .   6
       3.1.1  Collection Document  . . . . . . . . . . . . . . . . .   6
       3.1.2  Elements in a Collection Document  . . . . . . . . . .   6
       3.1.3  Collection Requests  . . . . . . . . . . . . . . . . .   7
     3.2  Introspection  . . . . . . . . . . . . . . . . . . . . . .   8
       3.2.1  Service Document . . . . . . . . . . . . . . . . . . .   8
     3.3  Entry Collection . . . . . . . . . . . . . . . . . . . . .   9
       3.3.1  Locating . . . . . . . . . . . . . . . . . . . . . . .  10
     3.4  Simple Resource Collection . . . . . . . . . . . . . . . .  10
       3.4.1  Locating . . . . . . . . . . . . . . . . . . . . . . .  10
       3.4.2  Request  . . . . . . . . . . . . . . . . . . . . . . .  10
     3.5  Atom Request and Response Body Constraints . . . . . . . .  11
       3.5.1  id . . . . . . . . . . . . . . . . . . . . . . . . . .  11
       3.5.2  link . . . . . . . . . . . . . . . . . . . . . . . . .  11
       3.5.3  title  . . . . . . . . . . . . . . . . . . . . . . . .  11
       3.5.4  summary  . . . . . . . . . . . . . . . . . . . . . . .  11
       3.5.5  content  . . . . . . . . . . . . . . . . . . . . . . .  12
       3.5.6  issued . . . . . . . . . . . . . . . . . . . . . . . .  12
       3.5.7  modified . . . . . . . . . . . . . . . . . . . . . . .  12
       3.5.8  created  . . . . . . . . . . . . . . . . . . . . . . .  12
       3.5.9  author . . . . . . . . . . . . . . . . . . . . . . . .  13
       3.5.10   contributor  . . . . . . . . . . . . . . . . . . . .  13
       3.5.11   generator  . . . . . . . . . . . . . . . . . . . . .  13
     3.6  Securing the Atom Protocol . . . . . . . . . . . . . . . .  13
       3.6.1  [@@TBD@@ CGI Authentication] . . . . . . . . . . . . .  14
   4.   Security Considerations  . . . . . . . . . . . . . . . . . .  14
   5.   IANA Considerations  . . . . . . . . . . . . . . . . . . . .  14
   6.   Appendix A - SOAP Enabling . . . . . . . . . . . . . . . . .  15
     6.1  Servers  . . . . . . . . . . . . . . . . . . . . . . . . .  15



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     6.2  Clients  . . . . . . . . . . . . . . . . . . . . . . . . .  15
   7.   Appendix B - Examples  . . . . . . . . . . . . . . . . . . .  15
     7.1  Example for a weblog . . . . . . . . . . . . . . . . . . .  15
     7.2  Example for a wiki . . . . . . . . . . . . . . . . . . . .  15
   8.   Revision History . . . . . . . . . . . . . . . . . . . . . .  15
   9.   Normative References . . . . . . . . . . . . . . . . . . . .  17
        Authors' Addresses . . . . . . . . . . . . . . . . . . . . .  18
        Intellectual Property and Copyright Statements . . . . . . .  19











































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1.  Introduction

   The Atom Publishing Protocol is an application-level protocol for
   publishing and editing Web resources using HTTP [RFC2616] and XML.

1.1  Notational Conventions

   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 [RFC2119].

1.2  Terminology

   Atom Entry: An Atom Entry is a fragment of a full Atom feed.  In this
      case, the fragment is a single 'entry' element and all its child
      elements.  Each Atom Entry describes a single Web resource,
      providing metadata and optionally a textual representation of that
      resource.

2.  The Atom Publishing Protocol Model

   The Atom Publishing Protocol is an application-level protocol for
   publishing and editing Web resources.  The primary way of interaction
   in the Atom Publishing Protocol is by managing collection of
   resources.  All collections support the same basic methods of
   interaction.  In addition, the resources belonging to collections
   also share the same interaction patterns.  Using the common HTTP
   verbs provides a pattern for working with all such Web resources:
   o  GET is used to retrieve a representation of a resource or perform
      a read-only query.
   o  PUT is used to update a known resource.
   o  POST is used to create a new dynamically-named resource.
   o  DELETE is used to remove a resource.

2.1  Atom Collections

   An Atom collection is a set of items all of the same type ("members"
   of the collection), where the "type" may be, for example: Atom entry,
   category, template, "simple resource", or any other classification of
   web resource.

   Each collection has a URI which is given in the introspection file.
   A GET on the collection URI MUST produce a collection document as
   defined in "3.X.1 Collection Document." That document describes PART
   OF the state of the collection.

   All the members of a collection have an "updated" property, and the
   collection is considered to be ordered by this property.  A single



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   collection document may not contain all of the members of a
   collection.  If a collection document is the response of a
   non-partial GET request, and does not contain all of the members of a
   collection, then it will contain the URI of the next collection
   document which will contain more of the collection members.  By
   traversing this list of collection documents a client can obtain all
   of the members of a collection.  The 'next' attribute will not be
   present in the response to a partial GET request.

2.1.1  Usage

   Below two usages are outlined for Atom Collections.  They are here to
   highlight common idioms for interacting with a Collection Resource
   and not a normative interaction pattern.

   The Atom Collection can be used by clients in two ways.  In the first
   case the client has attached to a site for the first time and is
   doing an initial syncronization, that is, retrieving a list of all
   the members of the collections and possibly retrieving all the
   members of the collection also.  The client can perform a non-partial
   GET on the collection resource and it will receive a collection
   document that either contains all the member of the collection, or
   the collection document root element 'collection' will contain a
   'next' attribute pointing to the next collection document.  By
   repeatedly following the 'next' attribute from document to document
   the client can find all the members of the collection.

   In the second case the client has already done an initial sync, and
   now needs to re-sync, because the client was just restarted, or some
   time has passed since a re-sync, etc.  The client does a partial GET
   on the collection document, supplying a Range header that begins from
   the last time the client sync'd to the current time.  The collection
   document returned will contain only those members of the collection
   that have changed since the last time the client syncronized.

2.1.2  Client and Server Interaction

   [[anchor5: ...]]

   This document does not specify the form of the URIs that are used.
   The URI space of each server is controlled, as defined by HTTP, by
   the server alone.  What this document does specify are the formats of
   the files that are exchanged and the actions that can be performed on
   the URIs embedded in those files.

3.  Functional Specification





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3.1  Collections

3.1.1  Collection Document

   A collection document is rooted by a <collection> element.  A
   collection element may have any number of <member> elements as
   children; each such element identifies a member of the collection.
   In some situations, a collection document may not contain every
   member of the collection itself.

   Whether complete or partial, the members in a collection document
   MUST constitute a consecutive sequence of the collection's members,
   ordered by their "updated" properties.  That is, a collection
   document MUST contain a contiguous subset of the members of the
   collection ordered by their 'updated' property.

3.1.2  Elements in a Collection Document

   A collection document MAY contain zero or more 'member' elements.

   Each 'member' element MUST include an 'href' attribute identifying a
   URL of the member resource.  The 'href' URI of a member resource is
   an "EditURI" under the terms of section 2, and MUST respond to the
   same HTTP methods as such an EditURI.

   Each 'member' element MAY include an "hrefreadonly" attribute.  This
   optional attribute identifies a URI which, on a GET request, responds
   equivalently to how the "href" URI would respond to the same request.
   Clients SHOULD NOT apply to this URI any HTTP methods that would be
   expected to modify the state of the resource (e.g.  PUT, POST or
   DELETE).  A PUT or POST request to this URI MAY NOT affect the
   underlying resource.  If the "hrefreadonly" attribute is not given,
   its value defaults to the "href" value.  If the "hrefreadonly"
   attribute is present, and its value is an empty string, then there is
   no URI that can be treated in the way such a value would be treated.

   Clients SHOULD use the "href" value to manipulate the resource within
   the context of the APP itself.  Clients SHOULD prefer the
   "hrefreadonly" value in any other context.  For example, if the
   resource is an image, a client may replace the image data using a PUT
   on the "href" value, and may even display a preview of the image by
   fetching the "href" URI.  But when creating a public, read-only
   reference to the same image resource, the client should use the
   "hrefreadonly" value.  If the "hrefreadonly" value is an empty
   string, the client SHOULD NOT make public reference to the "href"
   value.

   Each 'member' element MUST include a 'title' attribute, whose value



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   is a human-readable name or description for the item.  The values of
   'title' attributes are not required to be unique across all members
   of a collection.

   Each 'member' element MUST include an 'updated' attribute, whose
   value is the 'updated' property of the collection member whose format
   MUST conform to the date-time BNF rule in [RFC3339].

3.1.3  Collection Requests

3.1.3.1  Range: Header

   HTTP/1.1 allows a client to request that only part (a range of) the
   collection to be included within the response.  HTTP/1.1 uses range
   units in the Range header field.  A collection can be broken down
   into subranges according to the members 'updated' property.  If a
   Range: header is present in the request, its value explictly
   identifies the a time interval interval in which all the members
   'updated' property must fall to be included in the response.

   Range = "Range" ":" ranges-specifier

   The value of the Range: header should be a pair of ISO 8601 dates,
   separated by a slash character; either date may be optionally
   omitted, in which case the range is understood as stretching to
   infinity on that end.

   ranges-specifier = updated-ranges-specifier
   updated-ranges-specifier = updated-unit "=" updated-range
   updated-unit = "updated"
   updated-range = [iso-date] "/" [iso-date]

   The response to a collection request MUST be a collection document,
   all of whose 'member' elements fall within the requested range.  If
   no members fall in the requested range, the server MUST respond with
   a collection document containing no 'member' elements.

3.1.3.2  Accept-Ranges: Header

   The response to a non-partial GET request MUST include an
   Accept-Ranges header that indicates that the server accepts 'updated'
   range requests.

   Accept-Ranges     = "Accept-Ranges" ":" acceptable-ranges
   acceptable-ranges = updated-unit ( 1#range-unit )






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3.2  Introspection

   There are many different kinds of resources that can be managed
   through the APP, for example, entries, templates, users, etc.  The
   Service Document is a single document that lists all the facets of
   the APP that a site supports and also contains the URIs of all those
   resources.

3.2.1  Service Document

   The Service Document lists the resources that each site makes
   available.  The Service Resource returns an Service Document in
   response to a GET request.  Here is an example of an Service
   Document.

   <?xml version="1.0" encoding='utf-8'?>
   <service version="0.3" xmlns="http://purl.org/atom/ns#">
     <workspace title="Main Site" >
       <collection rel="entries" name="Entries"
         href="http://example.org/reilly/feed" />
       <collection rel="categories" name="Categories"
         href="http://example.org/reilly/cat" />
       <collection rel="templates" name="Templates"
         href="http://example.org/reilly/tmpl" />
       <collection rel="users" name="Users"
         href="http://example.org/reilly/users" />
       <collection rel="resource" name="Pictures"
         href="http://example.org/reilly/pic" />
     </workspace>
     <workspace title="b-links">
       <collection rel="entries" name="Entries"
         href="http://example.org/reilly/feed" />
       <collection rel="http://example.net/booklist" name="Books"
         href="http://example.org/reilly/books" />
     </workspace>
   </service>

   o  entries
   o  resource
   o  categories
   o  templates
   o  users
   The default for the rel attribute is 'resource'.  Extensibility for
   'rel' values is handled in the same manner as PaceFieldingLinks.
   Each 'collection' element in 'workspace' represents a single facet of
   the APP.  While a site must fully support each facet they list in
   their Service Document, a site does not need to support all the
   facets in this RFC.  Additionally, new facets may be added either



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   through vendor extension or follow-on RFCs.

3.2.1.1  Service Documet Elements

   The "service" element is the document element of a Service Document,
   acting as a container for service data associated with possibly
   multiple workspaces.  Its only child elements MUST be one or more
   'workspace' elements.  The 'service' element MUST have a single
   attribute 'version' whose content indicates the version of the Atom
   specification that the document conforms to.  The content of this
   attribute is unstructured text.  The version identifier for this
   specification is "1.0".

   The 'workspace' element element contains information elements about
   the collections of resources available for editing.  The only
   children of 'workspace' MUST be one or more "collection" elements.
   The 'workspace' element MUST have a single attribute 'title' whose
   content MUST NOT be empty and which is a human-readable name for the
   workspace.

   The 'collection' element describes various typed groups of resources
   available for editing or adding to.

3.3  Entry Collection

   Entries are managed through collections and as such entry collection
   and entries that are members of a collection must support all the
   operations enumerated above.

   An Edit Resource is used to edit a single entry.  Each entry that is
   editable MUST have a unique URI.  This URI supports both GET and PUT
   and they are used in tandem for an editing cycle.  The client GETs
   the representation which is formatted as an Atom entry.  The client
   may then update the entry and then PUT it back to the same URI.  The
   PUT will cause all the related resources to be updated, for example,
   the HTML representation.

   Note that the value of the content element in the Atom entry does not
   have to exactly match the content element for the same entry when it
   is represented in an Atom feed.  For example, a server may allow the
   client to post entries whose content is formatted as WikiML, yet the
   server may clean up such markup and transform it into well-formed
   XHTML before placing it in the publicly available Atom feed.  Another
   scenario is summaries--the EditURI is for editing the full content of
   an entry, but the server may only present excerpts when it produces
   an Atom feed.

   A client will send a DELETE to the EditURI to delete an entry.



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3.3.1  Locating

   For editing a site Entry, the link tag is used.  Note that a link tag
   is used in both HTML and in the Atom format.  A link tag of the
   following format points to the EditURI for a site.  In HTML, the link
   tags for editing are always found in the head element, while in Atom
   they may appear as children of the entry elements.

   <link rel="service.edit"
   type="application/atom+xml"
   href="URI for Editing goes here"
   title="Readable desc of the entry." />

   Note: The critical characteristic of this link tag is the @rel of
   'service.edit' and the @type of 'application/atom+xml'.

3.4  Simple Resource Collection

   Simple Resources are managed through collections and as such simple
   reource collections and simple resources that are members of the
   collection must support all the operations enumerated above.  Simple
   Resources can be images, templates, and any other non-entry
   resources.

3.4.1  Locating

   For creating a new non-entry resource, the link tag is used.  Note
   that a link tag is used in both HTML and in the Atom format.  A link
   tag of the following format points to the ResourcePostURI for a site.
   In HTML the link tags are always found in the head element, while in
   Atom they may appear as children of the Feed and entry elements.

   <link rel="resource.post" href="URI for Resource Posting goes here"
   title="The name of the site.">

3.4.2  Request

   The request contains a resource, sent through a standard HTTP POST,
   e.g.:

   POST /_do/exampleblog/post_resource HTTP/1.1
   Host: www.example.com
   Content-Type: image/jpeg
   Content-Length: nnn

   ...raw bytes of image go here...





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3.5  Atom Request and Response Body Constraints

   The Atom format is used as the representation of all the resources in
   this specification.  As it is used in differing contexts, there are
   different constraints of which elements may be present, and how their
   values should be interpreted.

3.5.1  id

   PostURI MUST NOT be present.
   FeedURI MUST be present.
   EditURI
      GET MUST be present.
      PUT MUST be present.

3.5.2  link

   PostURI MAY be present.  Servers MAY use the information to determine
      the URI of the created resource.  Relative URLs are to be
      interpreted relative to xml:base.
   FeedURI MUST be present.
   EditURI
      GET MUST be present.
      PUT MUST be present.

3.5.3  title

   PostURI MUST be present.  The element may be empty, to explicitly
      indicate "no title".  Servers SHOULD NOT try to generate a title
      if one is not provided.  The type attribute MAY be present, and if
      not it defaults to "text/plain".  If present, it MUST represent a
      MIME type that the server supports.  The mode attribute MAY be
      present.  If not present, it defaults to "xml".  If present, it
      MUST be "xml", "base64", or "escaped".
   FeedURI MUST be present.
   EditURI
      GET MUST be present.
      PUT MUST be present.  The element may be empty, to explicitly
         indicate "no title".  Servers SHOULD NOT try to generate a
         title if one is not provided.

3.5.4  summary

   PostURI MAY be present.  If not present, the server is welcome to
      produce its own summary.  If present but empty, the server SHOULD
      NOT generate a summary of its own.  The type attribute MAY be
      present.  If not, it defaults to "text/plain".  If present, it
      must represent a MIME type that the server supports.  The mode



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      attribute MAY be present and defaults to "xml".  If present, it
      must be "xml","base64", or "escaped".
   FeedURI MAY be present.
   EditURI
      GET MAY be present.
      PUT MAY be present.  The element may be empty, to explicitly
         indicate "no summary".  Servers SHOULD NOT try to generate a
         title if one is not provided.

3.5.5  content

   PostURI MAY be present but may be empty, to explicitly indicate "no
      content".  The type attribute MAY be present, but defaults to
      "text/plain" if not present.  It must represent a MIME type that
      the server supports.  The MODE attribute may be present and
      defaults to "xml" if not present.  It must be "xml","base64", or
      "escaped".
   FeedURI MAY be present.
   EditURI
      GET MAY be present.
      PUT MAY be present.  The element may be empty, to explicitly
         indicate "no content".

3.5.6  issued

   PostURI MUST be present, but may be empty, in which case it signifies
      "now" in the time zone of the server.
   FeedURI MUST be present.
   EditURI
      GET MUST be present.
      PUT MUST be present.  Server policy determines if an updated time
         is accepted.

3.5.7  modified

   PostURI MUST NOT be present.
   FeedURI MAY be present.
   EditURI
      GET MAY be present.
      PUT MAY be present.  The element may be empty, to explicitly
         indicate that 'now' on the server time is to be used.

3.5.8  created

   PostURI MAY be present.






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   FeedURI MAY be present.
   EditURI
      GET MAY be present.
      PUT MAY be present.  The server may or may not accept an updated
         value.  If the server does not allow updating the issued time
         then any PUT request with a different issued value MUST be
         rejected.

3.5.9  author

   PostURI MAY be present.  If not present, the server determines the
      author.  If present, and conflicting with valid values as
      determined by the server, then the server may change the value of
      author.
   FeedURI MAY be present.
   EditURI
      GET MAY be present.
      PUT MAY be present.

3.5.10  contributor

   PostURI MAY be present.
   FeedURI MAY be present.
   EditURI
      GET MAY be present.
      PUT MAY be present.

3.5.11  generator

   PostURI MUST be present and contain a URI.  The value of the element
      indicates the code base used to create this request.  MUST also
      have an attribute 'version' with a version number.
   FeedURI MUST NOT be present.
   EditURI
      GET MUST NOT be present.
      PUT MUST NOT be present.

3.6  Securing the Atom Protocol

   All instances of publishing Atom entries SHOULD be protected by
   authentication to prevent posting or editing by unknown sources.
   Atom servers and clients MUST support one of the following
   authentication mechanisms, and SHOULD support both.

   o  HTTP Digest Authentication [RFC2617]
   o  [@@TBD@@ CGI Authentication ref]

   Atom servers and clients MAY support encryption of the Atom session



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   using TLS [RFC2246].

   There are cases where an authentication mechanism may not be
   required, such as a publicly editable Wiki, or when using the PostURI
   to post comments to a site that does not require authentication to
   create comments.

3.6.1  [@@TBD@@ CGI Authentication]

   This authentication method is included as part of the protocol to
   allow Atom servers and clients that cannot use HTTP Digest
   Authentication but where the user can both insert its own HTTP
   headers and create a CGI program to authenticate entries to the
   server.  This scenario is common in environments where the user
   cannot control what services the server employs, but the user can
   write their own HTTP services.

4.  Security Considerations

   Because Atom is a publishing protocol, it is important that only
   authorized users can create and edit entries.

   The security of Atom is based on HTTP Digest Authentication and/or
   [@@TBD@@ CGI Authentication].  Any weaknesses in either of these
   authentication schemes will obviously affect the security of the Atom
   Publishing Protocol.

   Both HTTP Digest Authentication and [@@TBD@@ CGI Authentication] are
   susceptible to dictionary-based attacks on the shared secret.  If the
   shared secret is a password (instead of a random string with
   sufficient entropy), an attacker can determine the secret by
   exhaustively comparing the authenticating string with hashed results
   of the public string and dictionary entries.

   See RFC 2617 for more detailed description of the security properties
   of HTTP Digest Authentication.

   @@TBD@@ Talk here about using HTTP basic and digest authentication.

   @@TBD@@ Talk here about denial of service attacks using large XML
   files, or the billion laughs DTD attack.

5.  IANA Considerations

   This document has no actions for IANA.






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6.  Appendix A - SOAP Enabling

   All servers SHOULD support the following alternate interface
   mechanisms to enable a wider variety of clients to interact with Atom
   Publishing Protocol servers.  The following requirements are in
   addition to the ones listed in the Functional Specification Section.
   If a server supports SOAP Enabling then it MUST support all of the
   following.

6.1  Servers

   1.  All servers MUST support the limited use of the SOAPAction HTTP
       Header as described below in the Client section.
   2.  All servers MUST be able to process well formed XML.  Servers
       need not be able to handle processing instructions or DTDs.
   3.  Servers MUST accept content in a SOAP Envelope, and if they
       receive a request that is wrapped in a SOAP Envelope then they
       MUST wrap their responses in SOAP envelopes or produce a SOAP
       Fault.

6.2  Clients

   1.  Clients SHOULD use the appropriate HTTP Method when possible.
       When not possible, they should use POST and include a SOAPAction
       HTTP header which is constrained as follows:
   2.  SOAPAction: "http://schemas.xmlsoap.org/wsdl/http/[METHOD]"
   3.  Where [METHOD] is replaced by the desired HTTP Method.
   4.  Clients MAY wrap their XML payload in a SOAP Envelope.  If so,
       they must also wrap it in an element which exactly matches the
       HTTP Method.

7.  Appendix B - Examples

7.1  Example for a weblog

   Fill this in with an example for how all the above is used for a
   weblog.  Start with main HTML page, link tag of type service.feed to
   the 'introspection' file.  1.  Creating a new entry 2.  Finding an
   old entry 3.  editing an old entry 4.  commenting on a entry (via
   HTML and Atom)

7.2  Example for a wiki

   Fill this in like above but for a wiki.

8.  Revision History

   draft-ietf-atompub-protocol-03 - Incorporates PaceSliceAndDice3 and



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   PaceIntrospection.

   draft-ietf-atompub-protocol-02 - Incorporates Pace409Response,
   PacePostLocationMust, and PaceSimpleResourcePosting.

   draft-ietf-atompub-protocol-01 - Added in sections on Responses for
   the EditURI.  Allow 2xx for response to EditURI PUTs.  Elided all
   mentions of WSSE.  Started adding in some normative references.
   Added the section "Securing the Atom Protocol".  Clarified that it is
   possible that the PostURI and FeedURI could be the same URI.  Cleaned
   up descriptions for Response codes 400 and 500.

   Rev draft-ietf-atompub-protocol-00 - 5Jul2004 - Renamed the file and
   re-titled the document to conform to IETF submission guidelines.
   Changed MIME type to match the one selected for the Atom format.
   Numerous typographical fixes.  We used to have two 'Introduction'
   sections.  One of them was moved into the Abstract the other absorbed
   the Scope section.  IPR and copyright notifications were added.

   Rev 09 - 10Dec2003 - Added the section on SOAP enabled clients and
   servers.

   Rev 08 - 01Dec2003 - Refactored the specification, merging the
   Introspection file into the feed format.  Also dropped the
   distinction between the type of URI used to create new entries and
   the kind used to create comments.  Dropped user preferences.

   Rev 07 - 06Aug2003 - Removed the use of the RSD file for
   auto-discovery.  Changed copyright until a final standards body is
   chosen.  Changed query parameters for the search facet to all begin
   with atom- to avoid name collisions.  Updated all the Entries to
   follow the 0.2 version.  Changed the format of the search results and
   template file to a pure element based syntax.

   Rev 06 - 24Jul2003 - Moved to PUT for updating Entries.  Changed all
   the mime-types to application/x.atom+xml.  Added template editing.
   Changed 'edit-entry' to 'create-entry' in the Introspection file to
   more accurately reflect it's purpose.

   Rev 05 - 17Jul2003 - Renamed everything Echo into Atom.  Added
   version numbers in the Revision history.  Changed all the mime-types
   to application/atom+xml.

   Rev 04 - 15Jul2003 - Updated the RSD version used from 0.7 to 1.0.
   Change the method of deleting an Entry from POSTing <delete/> to
   using the HTTP DELETE verb.  Also changed the query interface to GET
   instead of POST.  Moved Introspection Discovery to be up under
   Introspection.  Introduced the term 'facet' for the services listed



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   in the Introspection file.

   Rev 03 - 10Jul2003 - Added a link to the Wiki near the front of the
   document.  Added a section on finding an Entry.  Retrieving an Entry
   now broken out into it's own section.  Changed the HTTP status code
   for a successful editing of an Entry to 205.

   Rev 02 - 7Jul2003 - Entries are no longer returned from POSTs,
   instead they are retrieved via GET.  Cleaned up figure titles, as
   they are rendered poorly in HTML.  All content-types have been
   changed to application/atom+xml.

   Rev 01 - 5Jul2003 - Renamed from EchoAPI.html to follow the more
   commonly used format: draft-gregorio-NN.html.  Renamed all references
   to URL to URI.  Broke out introspection into it's own section.  Added
   the Revision History section.  Added more to the warning that the
   example URIs are not normative.

9.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC2246]  Dierks, T. and C. Allen, "The TLS Protocol Version 1.0",
              RFC 2246, January 1999.

   [RFC2396]  Berners-Lee, T., Fielding, R. and L. Masinter, "Uniform
              Resource Identifiers (URI): Generic Syntax", RFC 2396,
              August 1998.

   [RFC2616]  Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
              Masinter, L., Leach, P. and T. Berners-Lee, "Hypertext
              Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.

   [RFC2617]  Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S.,
              Leach, P., Luotonen, A. and L. Stewart, "HTTP
              Authentication: Basic and Digest Access Authentication",
              RFC 2617, June 1999.

   [1]  <http://www.imc.org/atom-syntax/index.html>











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Authors' Addresses

   Joe Gregorio (editor)
   BitWorking, Inc
   1002 Heathwood Dairy Rd.
   Apex, NC  27502
   US

   Phone: +1 919 272 3764
   Email: joe@bitworking.com
   URI:   http://bitworking.com/


   Robert Sayre (editor)
   Boswijck Memex Consulting
   148 N 9th St. 4R
   Brooklyn, NY  11211
   US

   Email: rfsayre@boswijck.com
   URI:   http://boswijck.com






























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Acknowledgment

   Funding for the RFC Editor function is currently provided by the
   Internet Society.















































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