--- 1/draft-ietf-webdav-rfc2518bis-11.txt 2006-02-06 22:12:41.000000000 +0100 +++ 2/draft-ietf-webdav-rfc2518bis-12.txt 2006-02-06 22:12:42.000000000 +0100 @@ -1,18 +1,18 @@ -WebDAV L. Dusseault +WebDAV L. Dusseault, Ed. Internet-Draft OSAF -Obsoletes: 2518 (if approved) January 22, 2006 -Expires: July 26, 2006 +Obsoletes: 2518 (if approved) February 5, 2006 +Expires: August 9, 2006 HTTP Extensions for Distributed Authoring - WebDAV - draft-ietf-webdav-rfc2518bis-11 + draft-ietf-webdav-rfc2518bis-12 Status of this Memo 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 becomes aware will be disclosed, in accordance with Section 6 of BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that @@ -23,21 +23,21 @@ 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 July 26, 2006. + This Internet-Draft will expire on August 9, 2006. Copyright Notice Copyright (C) The Internet Society (2006). Abstract WebDAV consists of a set of methods, headers, and content-types ancillary to HTTP/1.1 for the management of resource properties, creation and management of resource collections, URL namespace @@ -55,221 +55,226 @@ 4.1. The Resource Property Model . . . . . . . . . . . . . . 11 4.2. Properties and HTTP Headers . . . . . . . . . . . . . . 11 4.3. Property Values . . . . . . . . . . . . . . . . . . . . 11 4.3.1. Example - Property with Mixed Content . . . . . . . 13 4.4. Property Names . . . . . . . . . . . . . . . . . . . . . 15 4.5. Source Resources and Output Resources . . . . . . . . . 15 5. Collections of Web Resources . . . . . . . . . . . . . . . . 16 5.1. HTTP URL Namespace Model . . . . . . . . . . . . . . . . 16 5.2. Collection Resources . . . . . . . . . . . . . . . . . . 16 6. Locking . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 - 6.1. Exclusive Vs. Shared Locks . . . . . . . . . . . . . . . 18 - 6.2. Required Support . . . . . . . . . . . . . . . . . . . . 19 - 6.3. Lock Creator . . . . . . . . . . . . . . . . . . . . . . 19 - 6.4. Lock Tokens . . . . . . . . . . . . . . . . . . . . . . 20 - 6.5. Lock Capability Discovery . . . . . . . . . . . . . . . 20 - 6.6. Active Lock Discovery . . . . . . . . . . . . . . . . . 21 - 6.7. Locks and Multiple Bindings . . . . . . . . . . . . . . 21 - 7. Write Lock . . . . . . . . . . . . . . . . . . . . . . . . . 22 - 7.1. Methods Restricted by Write Locks . . . . . . . . . . . 22 - 7.2. Write Locks and Lock Tokens . . . . . . . . . . . . . . 22 - 7.3. Write Locks and Properties . . . . . . . . . . . . . . . 23 - 7.4. Avoiding Lost Updates . . . . . . . . . . . . . . . . . 23 - 7.5. Write Locks and Unmapped URLs . . . . . . . . . . . . . 24 - 7.6. Write Locks and Collections . . . . . . . . . . . . . . 26 - 7.7. Write Locks and the If Request Header . . . . . . . . . 27 - 7.7.1. Example - Write Lock and COPY . . . . . . . . . . . 28 - 7.7.2. Example - Deleting a member of a locked collection . 28 - 7.8. Write Locks and COPY/MOVE . . . . . . . . . . . . . . . 29 - 7.9. Refreshing Write Locks . . . . . . . . . . . . . . . . . 30 - 8. HTTP Methods for Distributed Authoring . . . . . . . . . . . 31 - 8.1. General Request and Response Handling . . . . . . . . . 31 - 8.1.1. Use of XML . . . . . . . . . . . . . . . . . . . . . 31 - 8.1.2. Required Bodies in Requests . . . . . . . . . . . . 31 - 8.1.3. HTTP Headers for use in WebDAV . . . . . . . . . . . 31 - 8.1.4. ETag . . . . . . . . . . . . . . . . . . . . . . . . 32 - 8.1.5. Including error response bodies . . . . . . . . . . 32 - 8.1.6. Impact of Namespace Operations on Cache Validators . 33 - 8.2. PROPFIND Method . . . . . . . . . . . . . . . . . . . . 33 - 8.2.1. PROPFIND status codes . . . . . . . . . . . . . . . 35 - 8.2.2. Status codes for use with 207 (Multi-Status) . . . . 35 - 8.2.3. Example - Retrieving Named Properties . . . . . . . 36 - 8.2.4. Example - Retrieving Named and Dead Properties . . . 38 - 8.2.5. Example - Using 'propname' to Retrieve all - Property Names . . . . . . . . . . . . . . . . . . . 38 - 8.2.6. Example - Using 'allprop' . . . . . . . . . . . . . 40 - 8.3. PROPPATCH Method . . . . . . . . . . . . . . . . . . . . 42 - 8.3.1. Status Codes for use in 207 (Multi-Status) . . . . . 43 - 8.3.2. Example - PROPPATCH . . . . . . . . . . . . . . . . 44 - 8.4. MKCOL Method . . . . . . . . . . . . . . . . . . . . . . 45 - 8.4.1. MKCOL Status Codes . . . . . . . . . . . . . . . . . 46 - 8.4.2. Example - MKCOL . . . . . . . . . . . . . . . . . . 46 - 8.5. GET, HEAD for Collections . . . . . . . . . . . . . . . 47 - 8.6. POST for Collections . . . . . . . . . . . . . . . . . . 47 - 8.7. DELETE Requirements . . . . . . . . . . . . . . . . . . 47 - 8.7.1. DELETE for Collections . . . . . . . . . . . . . . . 48 - 8.7.2. Example - DELETE . . . . . . . . . . . . . . . . . . 48 - 8.8. PUT Requirements . . . . . . . . . . . . . . . . . . . . 49 - 8.8.1. PUT for Non-Collection Resources . . . . . . . . . . 49 - 8.8.2. PUT for Collections . . . . . . . . . . . . . . . . 50 - 8.9. COPY Method . . . . . . . . . . . . . . . . . . . . . . 50 - 8.9.1. COPY for Non-collection Resources . . . . . . . . . 50 - 8.9.2. COPY for Properties . . . . . . . . . . . . . . . . 51 - 8.9.3. COPY for Collections . . . . . . . . . . . . . . . . 51 - 8.9.4. COPY and Overwriting Destination Resources . . . . . 52 - 8.9.5. Status Codes . . . . . . . . . . . . . . . . . . . . 53 - 8.9.6. Example - COPY with Overwrite . . . . . . . . . . . 54 - 8.9.7. Example - COPY with No Overwrite . . . . . . . . . . 54 - 8.9.8. Example - COPY of a Collection . . . . . . . . . . . 55 - 8.10. MOVE Method . . . . . . . . . . . . . . . . . . . . . . 55 - 8.10.1. MOVE for Properties . . . . . . . . . . . . . . . . 56 - 8.10.2. MOVE for Collections . . . . . . . . . . . . . . . . 56 - 8.10.3. MOVE and the Overwrite Header . . . . . . . . . . . 57 - 8.10.4. Status Codes . . . . . . . . . . . . . . . . . . . . 57 - 8.10.5. Example - MOVE of a Non-Collection . . . . . . . . . 58 - 8.10.6. Example - MOVE of a Collection . . . . . . . . . . . 59 - 8.11. LOCK Method . . . . . . . . . . . . . . . . . . . . . . 59 - 8.11.1. Refreshing Locks . . . . . . . . . . . . . . . . . . 60 - 8.11.2. Depth and Locking . . . . . . . . . . . . . . . . . 61 - 8.11.3. Locking Unmapped URLs . . . . . . . . . . . . . . . 61 - 8.11.4. Lock Compatibility Table . . . . . . . . . . . . . . 62 - 8.11.5. LOCK Responses . . . . . . . . . . . . . . . . . . . 62 - 8.11.6. Example - Simple Lock Request . . . . . . . . . . . 63 - 8.11.7. Example - Refreshing a Write Lock . . . . . . . . . 65 - 8.11.8. Example - Multi-Resource Lock Request . . . . . . . 66 - 8.12. UNLOCK Method . . . . . . . . . . . . . . . . . . . . . 67 - 8.12.1. Status Codes . . . . . . . . . . . . . . . . . . . . 67 - 8.12.2. Example - UNLOCK . . . . . . . . . . . . . . . . . . 68 - 9. HTTP Headers for Distributed Authoring . . . . . . . . . . . 69 - 9.1. DAV Header . . . . . . . . . . . . . . . . . . . . . . . 69 - 9.2. Depth Header . . . . . . . . . . . . . . . . . . . . . . 69 - 9.3. Destination Header . . . . . . . . . . . . . . . . . . . 71 - 9.4. If Header . . . . . . . . . . . . . . . . . . . . . . . 71 - 9.4.1. No-tag-list Production . . . . . . . . . . . . . . . 72 - 9.4.2. Tagged-list Production . . . . . . . . . . . . . . . 72 - 9.4.3. Example - Tagged List If header in COPY . . . . . . 73 - 9.4.4. Not Production . . . . . . . . . . . . . . . . . . . 73 - 9.4.5. Matching Function . . . . . . . . . . . . . . . . . 74 - 9.4.6. If Header and Non-DAV Aware Proxies . . . . . . . . 74 - 9.5. Lock-Token Header . . . . . . . . . . . . . . . . . . . 75 - 9.6. Overwrite Header . . . . . . . . . . . . . . . . . . . . 75 - 9.7. Timeout Request Header . . . . . . . . . . . . . . . . . 75 - 10. Status Code Extensions to HTTP/1.1 . . . . . . . . . . . . . 77 - 10.1. 207 Multi-Status . . . . . . . . . . . . . . . . . . . . 77 - 10.2. 422 Unprocessable Entity . . . . . . . . . . . . . . . . 77 - 10.3. 423 Locked . . . . . . . . . . . . . . . . . . . . . . . 77 - 10.4. 424 Failed Dependency . . . . . . . . . . . . . . . . . 77 - 10.5. 507 Insufficient Storage . . . . . . . . . . . . . . . . 77 - 11. Use of HTTP Status Codes . . . . . . . . . . . . . . . . . . 78 - 11.1. 412 Precondition Failed . . . . . . . . . . . . . . . . 78 - 11.2. 414 Request-URI Too Long . . . . . . . . . . . . . . . . 78 - 12. Multi-Status Response . . . . . . . . . . . . . . . . . . . . 79 - 12.1. Response headers . . . . . . . . . . . . . . . . . . . . 79 - 12.2. URL Handling . . . . . . . . . . . . . . . . . . . . . . 79 - 12.3. Handling redirected child resources . . . . . . . . . . 80 - 12.4. Internal Status Codes . . . . . . . . . . . . . . . . . 80 - 13. XML Element Definitions . . . . . . . . . . . . . . . . . . . 81 - 13.1. activelock XML Element . . . . . . . . . . . . . . . . . 81 - 13.2. allprop XML Element . . . . . . . . . . . . . . . . . . 81 - 13.3. collection XML Element . . . . . . . . . . . . . . . . . 81 - 13.4. depth XML Element . . . . . . . . . . . . . . . . . . . 82 - 13.5. error XML Element . . . . . . . . . . . . . . . . . . . 82 - 13.6. exclusive XML Element . . . . . . . . . . . . . . . . . 82 - 13.7. href XML Element . . . . . . . . . . . . . . . . . . . . 82 - 13.8. include XML Element . . . . . . . . . . . . . . . . . . 83 - 13.9. location XML Element . . . . . . . . . . . . . . . . . . 83 - 13.10. lockentry XML Element . . . . . . . . . . . . . . . . . 83 - 13.11. lockinfo XML Element . . . . . . . . . . . . . . . . . . 83 - 13.12. lockroot XML Element . . . . . . . . . . . . . . . . . . 84 - 13.13. lockscope XML Element . . . . . . . . . . . . . . . . . 84 - 13.14. locktoken XML Element . . . . . . . . . . . . . . . . . 84 - 13.15. locktype XML Element . . . . . . . . . . . . . . . . . . 84 - 13.16. multistatus XML Element . . . . . . . . . . . . . . . . 85 - 13.17. prop XML element . . . . . . . . . . . . . . . . . . . . 85 - 13.18. propertyupdate XML element . . . . . . . . . . . . . . . 85 - 13.19. propfind XML Element . . . . . . . . . . . . . . . . . . 86 - 13.20. propname XML Element . . . . . . . . . . . . . . . . . . 86 - 13.21. propstat XML Element . . . . . . . . . . . . . . . . . . 86 - 13.22. remove XML element . . . . . . . . . . . . . . . . . . . 86 - 13.23. response XML Element . . . . . . . . . . . . . . . . . . 87 - 13.24. responsedescription XML Element . . . . . . . . . . . . 87 - 13.25. set XML element . . . . . . . . . . . . . . . . . . . . 87 - 13.26. shared XML Element . . . . . . . . . . . . . . . . . . . 88 - 13.27. status XML Element . . . . . . . . . . . . . . . . . . . 88 - 13.28. timeout XML Element . . . . . . . . . . . . . . . . . . 88 - 13.29. write XML Element . . . . . . . . . . . . . . . . . . . 89 - 14. DAV Properties . . . . . . . . . . . . . . . . . . . . . . . 90 - 14.1. creationdate Property . . . . . . . . . . . . . . . . . 90 - 14.2. displayname Property . . . . . . . . . . . . . . . . . . 91 - 14.3. getcontentlanguage Property . . . . . . . . . . . . . . 91 - 14.4. getcontentlength Property . . . . . . . . . . . . . . . 92 - 14.5. getcontenttype Property . . . . . . . . . . . . . . . . 92 - 14.6. getetag Property . . . . . . . . . . . . . . . . . . . . 93 - 14.7. getlastmodified Property . . . . . . . . . . . . . . . . 93 - 14.8. lockdiscovery Property . . . . . . . . . . . . . . . . . 94 - 14.8.1. Example - Retrieving DAV:lockdiscovery . . . . . . . 95 - 14.9. resourcetype Property . . . . . . . . . . . . . . . . . 96 - 14.10. supportedlock Property . . . . . . . . . . . . . . . . . 97 - 14.10.1. Example - Retrieving DAV:supportedlock . . . . . . . 98 - 15. Precondition/postcondition XML elements . . . . . . . . . . . 99 - 16. XML Extensibility in DAV . . . . . . . . . . . . . . . . . . 103 - 17. DAV Compliance Classes . . . . . . . . . . . . . . . . . . . 105 - 17.1. Class 1 . . . . . . . . . . . . . . . . . . . . . . . . 105 - 17.2. Class 2 . . . . . . . . . . . . . . . . . . . . . . . . 105 - 17.3. Class 'bis' . . . . . . . . . . . . . . . . . . . . . . 105 - 18. Internationalization Considerations . . . . . . . . . . . . . 106 - 19. Security Considerations . . . . . . . . . . . . . . . . . . . 108 - 19.1. Authentication of Clients . . . . . . . . . . . . . . . 108 - 19.2. Denial of Service . . . . . . . . . . . . . . . . . . . 108 - 19.3. Security through Obscurity . . . . . . . . . . . . . . . 109 - 19.4. Privacy Issues Connected to Locks . . . . . . . . . . . 109 - 19.5. Privacy Issues Connected to Properties . . . . . . . . . 109 - 19.6. Implications of XML Entities . . . . . . . . . . . . . . 110 - 19.7. Risks Connected with Lock Tokens . . . . . . . . . . . . 111 - 19.8. Hosting malicious scripts executed on client machines . 111 - 20. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 113 - 20.1. New URI Schemes . . . . . . . . . . . . . . . . . . . . 113 - 20.2. XML Namespaces . . . . . . . . . . . . . . . . . . . . . 113 - 20.3. Message Header Fields . . . . . . . . . . . . . . . . . 113 - 20.3.1. DAV . . . . . . . . . . . . . . . . . . . . . . . . 113 - 20.3.2. Depth . . . . . . . . . . . . . . . . . . . . . . . 113 - 20.3.3. Destination . . . . . . . . . . . . . . . . . . . . 114 - 20.3.4. If . . . . . . . . . . . . . . . . . . . . . . . . . 114 - 20.3.5. Lock-Token . . . . . . . . . . . . . . . . . . . . . 114 - 20.3.6. Overwrite . . . . . . . . . . . . . . . . . . . . . 114 - 20.3.7. Timeout . . . . . . . . . . . . . . . . . . . . . . 115 - 21. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 116 - 21.1. Previous Authors' Addresses . . . . . . . . . . . . . . 117 - 22. References . . . . . . . . . . . . . . . . . . . . . . . . . 118 - 22.1. Normative References . . . . . . . . . . . . . . . . . . 118 - 22.2. Informational References . . . . . . . . . . . . . . . . 119 - Appendix A. Notes on Processing XML Elements . . . . . . . . . . 120 - A.1. Notes on Empty XML Elements . . . . . . . . . . . . . . 120 - A.2. Notes on Illegal XML Processing . . . . . . . . . . . . 120 - A.3. Example - XML Syntax Error . . . . . . . . . . . . . . . 120 - A.4. Example - Unknown XML Element . . . . . . . . . . . . . 121 - Appendix B. Notes on HTTP Client Compatibility . . . . . . . . . 122 - Appendix C. The opaquelocktoken scheme and URIs . . . . . . . . 123 - Appendix D. Guidance for Clients Desiring to Authenticate . . . 124 - Appendix E. Summary of changes from RFC2518 . . . . . . . . . . 126 - E.1. Changes Notable to Server Implementors . . . . . . . . . 126 - E.2. Changes Notable to Client Implementors . . . . . . . . . 127 + 6.1. Lock Model . . . . . . . . . . . . . . . . . . . . . . . 18 + 6.2. Exclusive Vs. Shared Locks . . . . . . . . . . . . . . . 19 + 6.3. Required Support . . . . . . . . . . . . . . . . . . . . 20 + 6.4. Lock Creator . . . . . . . . . . . . . . . . . . . . . . 20 + 6.5. Lock Tokens . . . . . . . . . . . . . . . . . . . . . . 21 + 6.6. Lock Timeout . . . . . . . . . . . . . . . . . . . . . . 22 + 6.7. Lock Capability Discovery . . . . . . . . . . . . . . . 22 + 6.8. Active Lock Discovery . . . . . . . . . . . . . . . . . 22 + 6.9. Locks and Multiple Bindings . . . . . . . . . . . . . . 22 + 7. Write Lock . . . . . . . . . . . . . . . . . . . . . . . . . 23 + 7.1. Write Locks and Properties . . . . . . . . . . . . . . . 23 + 7.2. Avoiding Lost Updates . . . . . . . . . . . . . . . . . 24 + 7.3. Write Locks and Unmapped URLs . . . . . . . . . . . . . 25 + 7.4. Write Locks and Collections . . . . . . . . . . . . . . 27 + 7.5. Write Locks and the If Request Header . . . . . . . . . 28 + 7.5.1. Example - Write Lock and COPY . . . . . . . . . . . 29 + 7.5.2. Example - Deleting a member of a locked collection . 29 + 7.6. Write Locks and COPY/MOVE . . . . . . . . . . . . . . . 30 + 7.7. Refreshing Write Locks . . . . . . . . . . . . . . . . . 31 + 8. General Request and Response Handling . . . . . . . . . . . . 32 + 8.1. Use of XML . . . . . . . . . . . . . . . . . . . . . . . 32 + 8.2. URL Handling . . . . . . . . . . . . . . . . . . . . . . 32 + 8.2.1. Example - Correct URL Handling . . . . . . . . . . . 33 + 8.3. Required Bodies in Requests . . . . . . . . . . . . . . 34 + 8.4. HTTP Headers for use in WebDAV . . . . . . . . . . . . . 34 + 8.5. ETag . . . . . . . . . . . . . . . . . . . . . . . . . . 34 + 8.6. Including error response bodies . . . . . . . . . . . . 35 + 8.7. Impact of Namespace Operations on Cache Validators . . . 35 + 9. HTTP Methods for Distributed Authoring . . . . . . . . . . . 37 + 9.1. PROPFIND Method . . . . . . . . . . . . . . . . . . . . 37 + 9.1.1. PROPFIND status codes . . . . . . . . . . . . . . . 38 + 9.1.2. Status codes for use with 207 (Multi-Status) . . . . 39 + 9.1.3. Example - Retrieving Named Properties . . . . . . . 39 + 9.1.4. Example - Retrieving Named and Dead Properties . . . 41 + 9.1.5. Example - Using 'propname' to Retrieve all + Property Names . . . . . . . . . . . . . . . . . . . 41 + 9.1.6. Example - Using 'allprop' . . . . . . . . . . . . . 43 + 9.2. PROPPATCH Method . . . . . . . . . . . . . . . . . . . . 45 + 9.2.1. Status Codes for use in 207 (Multi-Status) . . . . . 46 + 9.2.2. Example - PROPPATCH . . . . . . . . . . . . . . . . 47 + 9.3. MKCOL Method . . . . . . . . . . . . . . . . . . . . . . 48 + 9.3.1. MKCOL Status Codes . . . . . . . . . . . . . . . . . 49 + 9.3.2. Example - MKCOL . . . . . . . . . . . . . . . . . . 49 + 9.4. GET, HEAD for Collections . . . . . . . . . . . . . . . 50 + 9.5. POST for Collections . . . . . . . . . . . . . . . . . . 50 + 9.6. DELETE Requirements . . . . . . . . . . . . . . . . . . 50 + 9.6.1. DELETE for Collections . . . . . . . . . . . . . . . 51 + 9.6.2. Example - DELETE . . . . . . . . . . . . . . . . . . 51 + 9.7. PUT Requirements . . . . . . . . . . . . . . . . . . . . 52 + 9.7.1. PUT for Non-Collection Resources . . . . . . . . . . 52 + 9.7.2. PUT for Collections . . . . . . . . . . . . . . . . 53 + 9.8. COPY Method . . . . . . . . . . . . . . . . . . . . . . 53 + 9.8.1. COPY for Non-collection Resources . . . . . . . . . 53 + 9.8.2. COPY for Properties . . . . . . . . . . . . . . . . 54 + 9.8.3. COPY for Collections . . . . . . . . . . . . . . . . 54 + 9.8.4. COPY and Overwriting Destination Resources . . . . . 55 + 9.8.5. Status Codes . . . . . . . . . . . . . . . . . . . . 56 + 9.8.6. Example - COPY with Overwrite . . . . . . . . . . . 57 + 9.8.7. Example - COPY with No Overwrite . . . . . . . . . . 57 + 9.8.8. Example - COPY of a Collection . . . . . . . . . . . 58 + 9.9. MOVE Method . . . . . . . . . . . . . . . . . . . . . . 58 + 9.9.1. MOVE for Properties . . . . . . . . . . . . . . . . 59 + 9.9.2. MOVE for Collections . . . . . . . . . . . . . . . . 59 + 9.9.3. MOVE and the Overwrite Header . . . . . . . . . . . 60 + 9.9.4. Status Codes . . . . . . . . . . . . . . . . . . . . 60 + 9.9.5. Example - MOVE of a Non-Collection . . . . . . . . . 61 + 9.9.6. Example - MOVE of a Collection . . . . . . . . . . . 62 + 9.10. LOCK Method . . . . . . . . . . . . . . . . . . . . . . 62 + 9.10.1. Creating a lock on existing resource . . . . . . . . 63 + 9.10.2. Refreshing Locks . . . . . . . . . . . . . . . . . . 63 + 9.10.3. Depth and Locking . . . . . . . . . . . . . . . . . 64 + 9.10.4. Locking Unmapped URLs . . . . . . . . . . . . . . . 64 + 9.10.5. Lock Compatibility Table . . . . . . . . . . . . . . 65 + 9.10.6. LOCK Responses . . . . . . . . . . . . . . . . . . . 65 + 9.10.7. Example - Simple Lock Request . . . . . . . . . . . 66 + 9.10.8. Example - Refreshing a Write Lock . . . . . . . . . 68 + 9.10.9. Example - Multi-Resource Lock Request . . . . . . . 69 + 9.11. UNLOCK Method . . . . . . . . . . . . . . . . . . . . . 70 + 9.11.1. Status Codes . . . . . . . . . . . . . . . . . . . . 70 + 9.11.2. Example - UNLOCK . . . . . . . . . . . . . . . . . . 71 + 10. HTTP Headers for Distributed Authoring . . . . . . . . . . . 72 + 10.1. DAV Header . . . . . . . . . . . . . . . . . . . . . . . 72 + 10.2. Depth Header . . . . . . . . . . . . . . . . . . . . . . 73 + 10.3. Destination Header . . . . . . . . . . . . . . . . . . . 74 + 10.4. If Header . . . . . . . . . . . . . . . . . . . . . . . 74 + 10.4.1. No-tag-list Production . . . . . . . . . . . . . . . 75 + 10.4.2. Tagged-list Production . . . . . . . . . . . . . . . 75 + 10.4.3. Example - Tagged List If header in COPY . . . . . . 76 + 10.4.4. Not Production . . . . . . . . . . . . . . . . . . . 76 + 10.4.5. Matching Function . . . . . . . . . . . . . . . . . 77 + 10.4.6. If Header and Non-DAV Aware Proxies . . . . . . . . 77 + 10.5. Lock-Token Header . . . . . . . . . . . . . . . . . . . 78 + 10.6. Overwrite Header . . . . . . . . . . . . . . . . . . . . 78 + 10.7. Timeout Request Header . . . . . . . . . . . . . . . . . 78 + 11. Status Code Extensions to HTTP/1.1 . . . . . . . . . . . . . 80 + 11.1. 207 Multi-Status . . . . . . . . . . . . . . . . . . . . 80 + 11.2. 422 Unprocessable Entity . . . . . . . . . . . . . . . . 80 + 11.3. 423 Locked . . . . . . . . . . . . . . . . . . . . . . . 80 + 11.4. 424 Failed Dependency . . . . . . . . . . . . . . . . . 80 + 11.5. 507 Insufficient Storage . . . . . . . . . . . . . . . . 80 + 12. Use of HTTP Status Codes . . . . . . . . . . . . . . . . . . 81 + 12.1. 412 Precondition Failed . . . . . . . . . . . . . . . . 81 + 12.2. 414 Request-URI Too Long . . . . . . . . . . . . . . . . 81 + 13. Multi-Status Response . . . . . . . . . . . . . . . . . . . . 82 + 13.1. Response headers . . . . . . . . . . . . . . . . . . . . 82 + 13.2. Handling redirected child resources . . . . . . . . . . 82 + 13.3. Internal Status Codes . . . . . . . . . . . . . . . . . 83 + 14. XML Element Definitions . . . . . . . . . . . . . . . . . . . 84 + 14.1. activelock XML Element . . . . . . . . . . . . . . . . . 84 + 14.2. allprop XML Element . . . . . . . . . . . . . . . . . . 84 + 14.3. collection XML Element . . . . . . . . . . . . . . . . . 84 + 14.4. depth XML Element . . . . . . . . . . . . . . . . . . . 85 + 14.5. error XML Element . . . . . . . . . . . . . . . . . . . 85 + 14.6. exclusive XML Element . . . . . . . . . . . . . . . . . 85 + 14.7. href XML Element . . . . . . . . . . . . . . . . . . . . 85 + 14.8. include XML Element . . . . . . . . . . . . . . . . . . 86 + 14.9. location XML Element . . . . . . . . . . . . . . . . . . 86 + 14.10. lockentry XML Element . . . . . . . . . . . . . . . . . 86 + 14.11. lockinfo XML Element . . . . . . . . . . . . . . . . . . 86 + 14.12. lockroot XML Element . . . . . . . . . . . . . . . . . . 87 + 14.13. lockscope XML Element . . . . . . . . . . . . . . . . . 87 + 14.14. locktoken XML Element . . . . . . . . . . . . . . . . . 87 + 14.15. locktype XML Element . . . . . . . . . . . . . . . . . . 87 + 14.16. multistatus XML Element . . . . . . . . . . . . . . . . 88 + 14.17. owner XML Element . . . . . . . . . . . . . . . . . . . 88 + 14.18. prop XML element . . . . . . . . . . . . . . . . . . . . 89 + 14.19. propertyupdate XML element . . . . . . . . . . . . . . . 89 + 14.20. propfind XML Element . . . . . . . . . . . . . . . . . . 89 + 14.21. propname XML Element . . . . . . . . . . . . . . . . . . 89 + 14.22. propstat XML Element . . . . . . . . . . . . . . . . . . 90 + 14.23. remove XML element . . . . . . . . . . . . . . . . . . . 90 + 14.24. response XML Element . . . . . . . . . . . . . . . . . . 90 + 14.25. responsedescription XML Element . . . . . . . . . . . . 91 + 14.26. set XML element . . . . . . . . . . . . . . . . . . . . 91 + 14.27. shared XML Element . . . . . . . . . . . . . . . . . . . 91 + 14.28. status XML Element . . . . . . . . . . . . . . . . . . . 92 + 14.29. timeout XML Element . . . . . . . . . . . . . . . . . . 92 + 14.30. write XML Element . . . . . . . . . . . . . . . . . . . 92 + 15. DAV Properties . . . . . . . . . . . . . . . . . . . . . . . 93 + 15.1. creationdate Property . . . . . . . . . . . . . . . . . 93 + 15.2. displayname Property . . . . . . . . . . . . . . . . . . 94 + 15.3. getcontentlanguage Property . . . . . . . . . . . . . . 94 + 15.4. getcontentlength Property . . . . . . . . . . . . . . . 95 + 15.5. getcontenttype Property . . . . . . . . . . . . . . . . 95 + 15.6. getetag Property . . . . . . . . . . . . . . . . . . . . 96 + 15.7. getlastmodified Property . . . . . . . . . . . . . . . . 96 + 15.8. lockdiscovery Property . . . . . . . . . . . . . . . . . 97 + 15.8.1. Example - Retrieving DAV:lockdiscovery . . . . . . . 98 + 15.9. resourcetype Property . . . . . . . . . . . . . . . . . 99 + 15.10. supportedlock Property . . . . . . . . . . . . . . . . . 100 + 15.10.1. Example - Retrieving DAV:supportedlock . . . . . . . 101 + 16. Precondition/postcondition XML elements . . . . . . . . . . . 102 + 17. XML Extensibility in DAV . . . . . . . . . . . . . . . . . . 106 + 18. DAV Compliance Classes . . . . . . . . . . . . . . . . . . . 108 + 18.1. Class 1 . . . . . . . . . . . . . . . . . . . . . . . . 108 + 18.2. Class 2 . . . . . . . . . . . . . . . . . . . . . . . . 108 + 18.3. Class 3 . . . . . . . . . . . . . . . . . . . . . . . . 108 + 19. Internationalization Considerations . . . . . . . . . . . . . 110 + 20. Security Considerations . . . . . . . . . . . . . . . . . . . 112 + 20.1. Authentication of Clients . . . . . . . . . . . . . . . 112 + 20.2. Denial of Service . . . . . . . . . . . . . . . . . . . 112 + 20.3. Security through Obscurity . . . . . . . . . . . . . . . 113 + 20.4. Privacy Issues Connected to Locks . . . . . . . . . . . 113 + 20.5. Privacy Issues Connected to Properties . . . . . . . . . 113 + 20.6. Implications of XML Entities . . . . . . . . . . . . . . 114 + 20.7. Risks Connected with Lock Tokens . . . . . . . . . . . . 115 + 20.8. Hosting Malicious Content . . . . . . . . . . . . . . . 115 + 21. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 116 + 21.1. New URI Schemes . . . . . . . . . . . . . . . . . . . . 116 + 21.2. XML Namespaces . . . . . . . . . . . . . . . . . . . . . 116 + 21.3. Message Header Fields . . . . . . . . . . . . . . . . . 116 + 21.3.1. DAV . . . . . . . . . . . . . . . . . . . . . . . . 116 + 21.3.2. Depth . . . . . . . . . . . . . . . . . . . . . . . 116 + 21.3.3. Destination . . . . . . . . . . . . . . . . . . . . 117 + 21.3.4. If . . . . . . . . . . . . . . . . . . . . . . . . . 117 + 21.3.5. Lock-Token . . . . . . . . . . . . . . . . . . . . . 117 + 21.3.6. Overwrite . . . . . . . . . . . . . . . . . . . . . 117 + 21.3.7. Timeout . . . . . . . . . . . . . . . . . . . . . . 118 + 22. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 119 + 22.1. Previous Authors' Addresses . . . . . . . . . . . . . . 120 + 23. References . . . . . . . . . . . . . . . . . . . . . . . . . 121 + 23.1. Normative References . . . . . . . . . . . . . . . . . . 121 + 23.2. Informational References . . . . . . . . . . . . . . . . 122 + Appendix A. Notes on Processing XML Elements . . . . . . . . . . 123 + A.1. Notes on Empty XML Elements . . . . . . . . . . . . . . 123 + A.2. Notes on Illegal XML Processing . . . . . . . . . . . . 123 + A.3. Example - XML Syntax Error . . . . . . . . . . . . . . . 123 + A.4. Example - Unexpected XML Element . . . . . . . . . . . . 124 + Appendix B. Notes on HTTP Client Compatibility . . . . . . . . . 125 + Appendix C. The opaquelocktoken scheme and URIs . . . . . . . . 126 + Appendix D. Guidance for Clients Desiring to Authenticate . . . 127 + Appendix E. Summary of changes from RFC2518 . . . . . . . . . . 129 + E.1. Changes for both Clients and Servers . . . . . . . . . . 129 + E.2. Changes Notable to Server Implementors . . . . . . . . . 129 + E.3. Changes Notable to Client Implementors . . . . . . . . . 130 Appendix F. Change Log (to be removed by RFC Editor before - publication) . . . . . . . . . . . . . . . . . . . . 129 - F.1. Changes from -05 to -06 . . . . . . . . . . . . . . . . 129 - F.2. Changes in -07 . . . . . . . . . . . . . . . . . . . . . 129 - F.3. Changes in -08 . . . . . . . . . . . . . . . . . . . . . 130 - F.4. Changes in -09 . . . . . . . . . . . . . . . . . . . . . 131 - F.5. Changes in -10 . . . . . . . . . . . . . . . . . . . . . 132 - F.6. Changes in -11 . . . . . . . . . . . . . . . . . . . . . 132 - Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 133 - Intellectual Property and Copyright Statements . . . . . . . . . 134 + publication) . . . . . . . . . . . . . . . . . . . . 132 + F.1. Changes from -05 to -06 . . . . . . . . . . . . . . . . 132 + F.2. Changes in -07 . . . . . . . . . . . . . . . . . . . . . 132 + F.3. Changes in -08 . . . . . . . . . . . . . . . . . . . . . 133 + F.4. Changes in -09 . . . . . . . . . . . . . . . . . . . . . 134 + F.5. Changes in -10 . . . . . . . . . . . . . . . . . . . . . 135 + F.6. Changes in -11 . . . . . . . . . . . . . . . . . . . . . 135 + F.7. Changes in -11 . . . . . . . . . . . . . . . . . . . . . 135 + Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 137 + Intellectual Property and Copyright Statements . . . . . . . . . 138 1. Introduction This document describes an extension to the HTTP/1.1 protocol that allows clients to perform remote web content authoring operations. This extension provides a coherent set of methods, headers, request entity body formats, and response entity body formats that provide operations for: Properties: The ability to create, remove, and query information @@ -295,45 +300,45 @@ This standard does not specify the versioning operations suggested by [RFC2291]. That work was done in a separate document, "Versioning Extensions to WebDAV" [RFC3253]. The sections below provide a detailed introduction to various WebDAV abstractions: resource properties (Section 4), collections of resources (Section 5), locks (Section 6) in general and write locks (Section 7) specifically. These abstractions are manipulated by the WebDAV-specific HTTP - methods (Section 8) and the new HTTP headers (Section 9) used with + methods (Section 9) and the new HTTP headers (Section 10) used with WebDAV methods. While the status codes provided by HTTP/1.1 are sufficient to describe most error conditions encountered by WebDAV methods, there are some errors that do not fall neatly into the existing categories. This specification defines new status codes developed for WebDAV - methods (Section 10) and describes existing HTTP status codes - (Section 11) as used in WebDAV. Since some WebDAV methods may - operate over many resources, the Multi-Status response (Section 12) + methods (Section 11) and describes existing HTTP status codes + (Section 12) as used in WebDAV. Since some WebDAV methods may + operate over many resources, the Multi-Status response (Section 13) has been introduced to return status information for multiple resources. Finally, this version of WebDAV introduces precondition - and postcondition (Section 15) XML elements in error response bodies. + and postcondition (Section 16) XML elements in error response bodies. WebDAV uses [XML] for property names and some values, and also uses XML to marshal complicated request and response. This specification - contains DTD and text definitions of all all properties (Section 14) - and all other XML elements (Section 13) used in marshalling. WebDAV - includes a few special rules on extending (Section 16) WebDAV XML + contains DTD and text definitions of all all properties (Section 15) + and all other XML elements (Section 14) used in marshalling. WebDAV + includes a few special rules on extending (Section 17) WebDAV XML marshalling in backwards-compatible ways. Finishing off the specification are sections on what it means for a - resource to be compliant with this specification (Section 17), on - internationalization support (Section 18), and on security - (Section 19). + resource to be compliant with this specification (Section 18), on + internationalization support (Section 19), and on security + (Section 20). 2. Notational Conventions 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 [RFC2616], including the rules about implied linear white-space. Since this augmented BNF uses the basic production rules provided in section 2.2 of [RFC2616], these rules apply to this document as well. @@ -358,23 +363,28 @@ "http" scheme URI makes it possible to submit HTTP protocol requests to the resource using the URI. Collection - A resource that contains a set of URLs, which identify and locate member resources and which meet the collections requirements (Section 5). Member URL - A URL which is a member of the set of URLs contained by a collection. - Internal Member URL - A Member URL that is immediately relative to - the URL of the collection (the definition of immediately relative is - given later (Section 5.2)). + Path Segment - Informally, the characters found between slashes ("/") + in a URI. Formally, as defined in Section 3.3 of [RFC3986]. + + Internal Member URL - A member URL that is immediately relative to + the URL of the collection. That is, the internal member URL is equal + to a containing collection's URL plus an additional path segment for + non-collection resources, or additional segment plus trailing slash + "/" for collection resources. Property - A name/value pair that contains descriptive information about a resource. Live Property - A property whose semantics and syntax are enforced by the server. For example, the live property DAV:getcontentlength has its value, the length of the entity returned by a GET request, automatically calculated by the server. Dead Property - A property whose semantics and syntax are not @@ -644,29 +654,25 @@ namespace be consistent -- a WebDAV-compatible resource may not have a parent collection. However, certain WebDAV methods are prohibited from producing results that cause namespace inconsistencies. Although implicit in [RFC2616] and [RFC3986], any resource, including collection resources, MAY be identified by more than one URI. For example, a resource could be identified by multiple HTTP URLs. 5.2. Collection Resources - A collection is a resource whose state consists of at least a list of - internal member URLs and a set of properties, but which may have - additional state such as entity bodies returned by GET. An internal - member URL MUST be immediately relative to a base URL of the - collection. That is, the internal member URL is equal to a - containing collection's URL plus an additional segment for non- - collection resources, or additional segment plus trailing slash "/" - for collection resources, where segment is defined in section 3.3 of - [RFC3986]. + Collection resources differ from other resources in that they also + act as containers. A collection is a resource whose state consists + of at least a set of mappings between path segments and resources, + and a set of properties on the collection itself. A collection MAY + have additional state such as entity bodies returned by GET. Any given internal member URL MUST only belong to the collection once, i.e., it is illegal to have multiple instances of the same URL in a collection. Properties defined on collections behave exactly as do properties on non-collection resources. For all WebDAV compliant resources A and B, identified by URLs U and V, for which U is immediately relative to V, B MUST be a collection that has U as an internal member URL. So, if the resource with URL http://example.com/bar/blah is WebDAV compliant and if the resource @@ -717,27 +723,75 @@ a resource while it is being edited. In this way, a client can prevent the "lost update" problem. This specification allows locks to vary over two client-specified parameters, the number of principals involved (exclusive vs. shared) and the type of access to be granted. This document defines locking for only one access type, write. However, the syntax is extensible, and permits the eventual specification of locking for other access types. -6.1. Exclusive Vs. Shared Locks +6.1. Lock Model - The most basic form of lock is an exclusive lock. Only one exclusive - lock may exist on any resource, whether it is directly or indirectly - locked (Section 7.6). Exclusive locks avoid having to merge results, - without requiring any coordination other than the methods described - in this specification. + This section provides a concise model for how locking behaves. Later + sections will provide more detail on some of the concepts and refer + back to these model statements. Normative statements related to LOCK + and UNLOCK handling can be found in the sections on those methods, + whereas normative statements that cover any method are gathered here. + + 1. A lock either directly or indirectly locks a resource. + + 2. A resource becomes directly locked when a LOCK request to the URL + of that resource creates a new lock. The "lock-root" of the new + lock is that URL. If at the time of the request, the URL is not + mapped to a resource, a new empty resource is created and + directly locked. + + 3. An exclusive lock (Section 6.2) conflicts with any other kind of + lock on the same resource, whether either lock is direct or + indirect. A server MUST NOT create conflicting locks on a + resource. + + 4. For a collection that is locked with an infinite depth lock L, + all member resources are indirectly locked. Changes in + membership of a such a collection affect the set of indirectly + locked resources: + + * If an internal member resource is added to the collection, and + if the new member resource does not already have a conflicting + lock, then the resource MUST become indirectly locked by L. + + * If an internal member resource stops being a member of the + collection, then the resource MUST no longer be indirectly + locked by L. + + 5. Each lock is identified by a single unique lock token + (Section 6.5). + + 6. An UNLOCK request deletes the lock with the specified lock token, + provided that the request is addressed to a resource that is + either directly or indirectly locked by that lock. After a lock + is deleted, no resource is locked by that lock. + + 7. A lock token is "submitted" in a request when it appears in an If + header (the Write Lock (Section 7) section discusses when token + submission is required for write locks). + + 8. If a request causes the lock-root of any lock to become an + unmapped URL, then the lock MUST also be deleted by that request. + +6.2. Exclusive Vs. Shared Locks + + The most basic form of lock is an exclusive lock. Exclusive locks + avoid having to deal with content change conflicts, without requiring + any coordination other than the methods described in this + specification. 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 mechanism for principals to indicate that they intend to exercise their access rights. Shared locks are provided for this case. A shared lock allows multiple principals to receive a lock. Hence any principal with appropriate access can use the lock. With shared locks there are two trust sets that affect a resource. The first trust set is created by access permissions. Principals who @@ -765,71 +819,77 @@ telephone conversation, Email, etc.) The intent of a shared lock is to let collaborators know who else may be working on a resource. Shared locks are included because experience from web distributed authoring systems has indicated that exclusive locks are often too rigid. An exclusive lock is used to enforce a particular editing process: take out an exclusive lock, read the resource, perform edits, write the resource, release the lock. This editing process has the problem that locks are not always properly released, for example when a program crashes, or when a lock creator leaves without - unlocking a resource. While both timeouts and administrative action - can be used to remove an offending lock, neither mechanism may be - available when needed; the timeout may be long or the administrator - may not be available. + unlocking a resource. While both timeouts (Section 6.6) and + administrative action can be used to remove an offending lock, + neither mechanism may be available when needed; the timeout may be + long or the administrator may not be available. -6.2. Required Support + A successful request for a new shared lock MUST result in the + generation of a unique lock token associated with the requesting + principal. Thus if five principals have taken out shared write locks + on the same resource there will be five locks and five lock tokens, + one for each principal. + +6.3. Required Support A WebDAV compliant resource is not required to support locking in any form. If the resource does support locking it may choose to support any combination of exclusive and shared locks for any access types. The reason for this flexibility is that locking policy strikes to the very heart of the resource management and versioning systems employed by various storage repositories. These repositories require control over what sort of locking will be made available. For example, some repositories only support shared write locks while others only provide support for exclusive write locks while yet others use no locking at all. As each system is sufficiently different to merit exclusion of certain locking features, this specification leaves locking as the sole axis of negotiation within WebDAV. -6.3. Lock Creator +6.4. Lock Creator The creator of a lock has special privileges to use the locked resource. The server MUST restrict the usage of a lock token to the creator of the lock, both for shared and exclusive locks. For multi- user shared lock cases, each authenticated principal MUST obtain its own shared lock. The server MAY allow privileged users other than the lock creator to destroy a lock (for example, the resource owner or an administrator) as a special case of lock usage. If an anonymous user requests a lock, the server MAY refuse the request. -6.4. Lock Tokens +6.5. Lock Tokens A lock token is a type of state token, represented as a URI, which identifies a particular lock. Each lock has exactly one unique lock token generated by the server. Clients MUST NOT attempt to interpret lock tokens in any way. Lock token URIs MUST be unique across all resources for all time. This uniqueness constraint allows lock tokens to be submitted across resources and servers without fear of confusion. Since lock tokens are unique, a client MAY submit a lock token in an If header on a resource other than the one that returned it. When a LOCK operation creates a new lock, the new lock token is - returned in the Lock-Token response header defined in Section 9.5, + returned in the Lock-Token response header defined in Section 10.5, and also in the body of the response. Submitting a lock token does not confer full privilege to use the lock token or modify the locked resource. Write access and other privileges MUST be enforced through normal privilege or authentication mechanisms, not based on the possible obscurity of lock token values. Servers MAY make lock tokens publicly readable (e.g. in the DAV: lockdiscovery property). One use case for making lock tokens @@ -842,106 +902,118 @@ This specification encourages servers to create UUIDs for lock tokens, and to use the URI form defined by "A Universally Unique Identifier (UUID) URN Namespace" ([RFC4122]). However servers are free to use any URI (e.g. from another scheme) so long as it meets the uniqueness requirements. For example, a valid lock token might be constructed using the "opaquelocktoken" scheme defined in Appendix C. Example: "urn:uuid:f81d4fae-7dec-11d0-a765-00a0c91e6bf6" -6.5. Lock Capability Discovery +6.6. Lock Timeout + + A lock MAY have a limited lifetime. The lifetime is suggested by the + client when creating or refreshing the lock, but the server + ultimately chooses the timeout value. Servers MUST remove locks + reasonably soon after the timeout expires if the lock is not + refreshed and given a new timeout. + + Clients MUST assume that locks may arbitrarily disappear at any time, + regardless of the value given in the Timeout header. The Timeout + header only indicates the behavior of the server if extraordinary + circumstances do not occur. For example, a sufficiently privileged + user may remove a lock at any time or the system may crash in such a + way that it loses the record of the lock's existence. + +6.7. Lock Capability Discovery 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, or perform some form of discovery to determine what lock capabilities the server supports. This is known as lock capability discovery. A client can determine what lock types the server supports by retrieving the DAV:supportedlock property. Any DAV compliant resource that supports the LOCK method MUST support the DAV:supportedlock property. -6.6. Active Lock Discovery +6.8. Active Lock Discovery 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 who the first principal is. For this purpose the DAV:lockdiscovery property is provided. This property lists all outstanding locks, describes their type, and MAY even provide the lock tokens. Any DAV compliant resource that supports the LOCK method MUST support the DAV:lockdiscovery property. -6.7. Locks and Multiple Bindings +6.9. Locks and Multiple Bindings A resource may be made available through more than one URI. A lock MUST cover the resource as well as the URI to which the LOCK request was addressed. The lock MAY cover other URIs mapped to the same resource as well. 7. 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. An exclusive write lock will prevent parallel changes to a resource - by any principal other than the write lock holder. In general terms, - changes affected by write locks include changes to: - - o the content of the resource - - o any dead property of the resource + by any principal other than the lock creator and in any case where + the lock token is not submitted (e.g. by a client process other than + the one holding the lock). - o any live property defined to be lockable (all properties defined - in this specification are lockable) + Clients MUST submit a lock-token they are authorized to use in any + request which modifies a write-locked resource. The list of + modifications covered by a write-lock include: - o the direct membership of the resource, if it is a collection + 1. A change to any of the following aspects of any write-locked + resource: - o the URL/location of a resource + * any variant, - The next few sections describe in more specific terms how write locks - interact with various operations. + * any dead property, -7.1. Methods Restricted by Write Locks + * any live property which is lockable (a live property is + lockable unless otherwise defined.) - A server MUST reject any write request that alters a write-locked - resource unless a valid lock token is provided. The write operations - defined in HTTP and WebDAV are PUT, POST, PROPPATCH, LOCK, UNLOCK, - MOVE, COPY (for the destination resource), DELETE, and MKCOL. All - other HTTP/WebDAV methods, GET in particular, function independently - of the lock. A shared write lock prevents the same operations - (except additional requests for shared write locks), however it also - allows access by any principal that has a shared write lock on the - same resource. + 2. For collections, any modification of an internal member URI. An + internal member URI of a collection is considered to be modified + if it is added, removed, or identifies a different resource. + More discussion on write locks and collections is found in + Section 7.4. - Note, however, that as new methods are created it will be necessary - to specify how they interact with a write lock. + 3. A modification of the mapping of the root of the write lock, + either to another resource or to no resource (e.g. DELETE). -7.2. Write Locks and Lock Tokens + Of the methods defined in HTTP and WebDAV, PUT, POST, PROPPATCH, + LOCK, UNLOCK, MOVE, COPY (for the destination resource), DELETE, and + MKCOL are affected by write locks. All other HTTP/WebDAV methods + defined so far, GET in particular, function independently of a write + lock. - A successful request for an exclusive or shared write lock MUST - result in the generation of a unique lock token associated with the - requesting principal. Thus if five principals have a shared write - lock on the same resource there will be five lock tokens, one for - each principal. + The next few sections describe in more specific terms how write locks + interact with various operations. -7.3. Write Locks and Properties +7.1. Write Locks and Properties 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 change, even while locked, due to the requirements of their schemas. + Only dead properties and live properties defined to respect locks are guaranteed not to change while write locked. -7.4. Avoiding Lost Updates +7.2. Avoiding Lost Updates Although the write locks provide some help in preventing lost updates, they cannot guarantee that updates will never be lost. Consider the following scenario: 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. Client A doesn't lock the document, but does a GET and begins @@ -973,21 +1045,21 @@ 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. -7.5. Write Locks and Unmapped URLs +7.3. Write Locks and Unmapped URLs WebDAV provides the ability to lock an unmapped URL in order to reserve the name for use. This is a simple way to avoid the lost- update problem on the creation of a new resource (another way is to use If-None-Match header specified in HTTP 1.1). It has the side benefit of locking the new resource immediately for use of the creator. Note that the lost-update problem is not an issue for collections because MKCOL can only be used to create a collection, not to @@ -1036,62 +1108,62 @@ o The server converts the lock-null resource into a collection if a MKCOL request to the URL is successful (though interoperability experience showed that not all servers followed this requirement). o Property values were defined for DAV:lockdiscovery and DAV: supportedlock properties but not necessarily for other properties like DAV:getcontenttype. In the "locked empty resource" model, which is now the recommended implementation, a resource created with a LOCK is empty but otherwise - behaves in every way as a normal resource. A locked empty resource: + behaves in every way as a normal resource. It behaves as a same + resource that would result from a PUT request with an empty body (and + where a Content-Type and Content-Language was not specified), + followed by a LOCK request to the same resource. Following from this + model, a locked empty resource: o Can be read, deleted, moved, copied, and in all ways behave as a regular resource, not a lock-null resource. o Appears as a member of its parent collection. o SHOULD NOT disappear when its lock goes away (clients must therefore be responsible for cleaning up their own mess, as with any other operation or any non-empty resource) - o SHOULD default to having no content type. - o MAY NOT have values for properties like DAV:getcontentlanguage which haven't been specified yet by the client. o Can be updated (have content added) with a PUT request. o MUST NOT be converted into a collection. The server MUST fail a MKCOL request (as it would with a MKCOL request to any existing non-collection resource). o MUST have defined values for DAV:lockdiscovery and DAV: supportedlock properties. o The response MUST indicate that a resource was created, by use of the "201 Created" response code (a LOCK request to an existing resource instead will result in 200 OK). The body must still include the DAV:lockdiscovery property, as with a LOCK request to an existing resource. The client is expected to update the locked empty resource shortly - after locking it, using PUT and possibly PROPPATCH. When the client - uses PUT to overwrite a locked empty resource the client MUST supply - a Content-Type if any is known. + after locking it, using PUT and possibly PROPPATCH. Clients can easily interoperate both with servers that support the old model "lock-null resources" and the recommended model of "locked empty resources" by only attempting PUT after a LOCK to an unmapped URL, not MKCOL or GET. -7.6. Write Locks and Collections +7.4. Write Locks and Collections A write lock on a collection, whether created by a "Depth: 0" or "Depth: infinity" lock request, prevents the addition or removal of member URLs of the collection by principals other than the lock creator. A zero-depth lock on a collection affects changes to the direct membership of that collection. When a principal issues a write request to create a new resource in a write locked collection, or isses a DELETE, MOVE or other request that would remove an existing @@ -1129,33 +1201,33 @@ into an unlocked collection is thereafter unlocked. o Any indirectly locked resource moved out of a locked source collection into a depth-infinity locked target collection remains indirectly locked but is now within the scope of the lock on the target collection (the target collection's lock token will thereafter be required to make further changes). If a depth-infinity write LOCK request is issued to a collection containing member URLs identifying resources that are currently - locked in a manner which conflicts with the write lock, the request - MUST fail with a 423 (Locked) status code, and the response SHOULD - contain the 'no-conflicting-lock' precondition. + locked in a manner which conflicts with the new lock (see Section 6.1 + point 3), the request MUST fail with a 423 (Locked) status code, and + the response SHOULD contain the 'no-conflicting-lock' precondition. If a lock creator causes the URL of a resource to be added as an internal member URL of a depth-infinity locked collection then the new resource MUST be automatically 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 collection /a/b/ is write locked and the resource /c is moved to /a/b/c then resource /a/b/c will be added to the write lock. -7.7. Write Locks and the If Request Header +7.5. Write Locks and the If Request Header If a user agent is not required to have knowledge about a lock when 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 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 resource. In this scenario, the PUT succeeds because locks are associated with a principal, not a program, and thus program B, because it is acting with principal A's credential, is allowed to perform the PUT. However, had program B known about the lock, it @@ -1166,109 +1238,109 @@ same authorization. In order to prevent these collisions a lock token MUST be submitted by an authorized principal for all locked resources that a method may change or the method MUST fail. A lock token is submitted when it appears in an If header. For example, if a resource is to be moved and both the source and destination are locked then two lock tokens must be submitted in the if header, one for the source and the other for the destination. -7.7.1. Example - Write Lock and COPY +7.5.1. Example - Write Lock and COPY >>Request COPY /~fielding/index.html HTTP/1.1 - Host: www.ics.uci.edu - Destination: http://www.ics.uci.edu/users/f/fielding/index.html - If: + Host: www.example.com + Destination: http://www.example.com/users/f/fielding/index.html + If: () >>Response HTTP/1.1 204 No Content In this example, even though both the source and destination are locked, only one lock token must be submitted, for the lock on the destination. This is because the source resource is not modified by a COPY, and hence unaffected by the write lock. In this example, user agent authentication has previously occurred via a mechanism outside the scope of the HTTP protocol, in the underlying transport layer. -7.7.2. Example - Deleting a member of a locked collection +7.5.2. Example - Deleting a member of a locked collection Consider a collection "/locked" exclusively write-locked with Depth: Infinity, and an attempt to delete an internal member "/locked/ member": >>Request DELETE /locked/member HTTP/1.1 Host: example.com >>Response HTTP/1.1 423 Locked Content-Type: application/xml; charset="utf-8" Content-Length: xxxx - + /locked/ - + Thus the client would need to submit the lock token with the request to make it succeed. To do that, various forms of the If header (see - Section 9.4) could be used. + Section 10.4) could be used. "No-Tag-List" format: If: () "Tagged-List" format, for "http://example.com/locked/": If: () "Tagged-List" format, for "http://example.com/locked/member": If: () Note that for the purpose of submitting the lock token the actual form doesn't matter; what's relevant is that the lock token appears in the If header, and that the If header itself evaluates to true. -7.8. Write Locks and COPY/MOVE +7.6. 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 locked with "Depth: infinity", then the resource will be added to the lock. A successful MOVE request on a write locked resource MUST NOT move the write lock with the resource. However, if there is an existing lock at the destination, the server MUST add the moved resource to the destination lock scope. For example, if the MOVE makes the resource a child of a collection that is locked with "Depth: infinity", then the resource will be added to that collection's lock. Additionally, if a resource locked with "Depth: infinity" is moved to a destination that is within the scope of the same lock (e.g., within the URL namespace tree covered by the lock), the moved resource will again be a added to the lock. In both these examples, as specified - in Section 7.7, an If header must be submitted containing a lock + in Section 7.5, an If header must be submitted containing a lock token for both the source and destination. -7.9. Refreshing Write Locks +7.7. 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. @@ -1277,25 +1349,23 @@ 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. Note that timeout is measured in seconds remaining until expiration. If an error is received in response to a refresh LOCK request the client MUST NOT assume that the lock was refreshed. -8. HTTP Methods for Distributed Authoring - -8.1. General Request and Response Handling +8. General Request and Response Handling -8.1.1. Use of XML +8.1. Use of XML In HTTP/1.1, method parameter information was exclusively encoded in HTTP headers. Unlike HTTP/1.1, WebDAV encodes method parameter information either in an [XML] request entity body, or in an HTTP header. The use of XML to encode method parameters was motivated by the ability to add extra XML elements to existing structures, providing extensibility; and by XML's ability to encode information in ISO 10646 character sets, providing internationalization support. In addition to encoding method parameters, XML is used in WebDAV to @@ -1308,137 +1378,213 @@ All XML used in either requests or responses MUST be, at minimum, well formed and use namespaces correctly. If a server receives XML that is not well-formed then the server MUST reject the entire request with a 400 (Bad Request). If a client receives XML that is not well-formed in a response then the client MUST NOT assume anything about the outcome of the executed method and SHOULD treat the server as malfunctioning. Note that processing XML submitted by an untrusted source may cause risks connected to privacy, security, and service quality (see - Section 19). Servers MAY reject questionable requests (even though + Section 20). Servers MAY reject questionable requests (even though they consist of well-formed XML), for instance with a 400 (Bad Request) status code and an optional response body explaining the problem. -8.1.2. Required Bodies in Requests +8.2. URL Handling + + URLs appear in many places in requests and responses. + Interoperability experience with [RFC2518] showed that many clients + parsing Multi-Status responses did not fully implement the full + Reference Resolution defined in Section 5 of [RFC3986]. Thus, + servers in particular need to be careful in handling URLs in + responses, to ensure that clients have enough context to be able to + interpret all the URLs. The rules in this section apply not only to + resource URLs in the 'href' element in Multi-Status responses, but + also to the Destination and If header resource URLs. + + The sender has a choice between two approaches: using a relative + reference, which is resolved against the Request-URI, or a full URI. + + A sender SHOULD generally be consistent once it has chosen one of + these approaches, but a server MUST ensure that every 'href' value + within a Multi-Status response uses the same format. + + WebDAV only uses one form of relative reference in its extensions, + the absolute path. + + Simple-ref = absolute-URI | ( path-absolute [ "?" query ] ) + + The absolute-URI and path-absolute productions are defined in section + 4.3 and 4.1 of [RFC3986]. + + Within Simple-ref productions, senders MUST NOT: + + o use dot-segments ("." or ".."), or + + o have prefixes that do not match the Request-URI (using the + comparison rules defined in Section 3.2.3 of [RFC2616]). + + Identifiers for collections SHOULD end in a '/' character. + +8.2.1. Example - Correct URL Handling + + Consider the collection http://example.com/sample/ with the internal + member URL http://example.com/sample/a%20test and the PROPFIND + request below: + + >>Request: + + PROPFIND /sample/ HTTP/1.1 + Host: example.com + Depth: 1 + + In this case, the server should return two 'href' elements containing + either + + o 'http://example.com/sample/' and + 'http://example.com/sample/a%20test', or + + o '/sample/' and '/sample/a%20test' + + Note that even though the server may be storing the member resource + internally as 'a test', it has to be percent-encoded when used inside + a URI reference (see Section 2.1 of [RFC3986]). Also note that a + legal URI may still contain characters that need to be escaped within + XML character data, such as the ampersand character. + +8.3. Required Bodies in Requests Some of these new methods do not define bodies. Servers MUST examine all requests for a body, even when a body was not expected. In cases where a request body is present but would be ignored by a server, the server MUST reject the request with 415 (Unsupported Media Type). This informs the client (which may have been attempting to use an extension) that the body could not be processed as they intended. -8.1.3. HTTP Headers for use in WebDAV +8.4. HTTP Headers for use in WebDAV HTTP defines many headers that can be used in WebDAV requests and responses. Not all of these are appropriate in all situations and some interactions may be undefined. Note that HTTP 1.1 requires the Date header in all responses if possible (see section 14.18, [RFC2616]). The server MUST do authorization checks before checking any HTTP conditional header. -8.1.4. ETag +8.5. ETag HTTP 1.1 recommends the use of the ETag header in responses to GET and PUT requests. Correct use of ETags is even more important in a distributed authoring environment, because ETags are necessary along with locks to avoid the lost-update problem. A client might fail to renew a lock, for example when the lock times out and the client is accidentally offline or in the middle of a long upload. When a client fails to renew the lock, it's quite possible the resource can still be relocked and the user can go on editing, as long as no changes were made in the meantime. ETags are required for the client to be able to distinguish this case. Otherwise, the client is forced to ask the user whether to overwrite the resource on the server without even being able to tell the user whether it has changed. Timestamps do not solve this problem nearly as well as ETags. - WebDAV servers SHOULD support strong ETags for all resources that may - be PUT. If ETags are supported for a resource, the server MUST - return the ETag header in all PUT and GET responses to that resource. + Strong ETags are much more useful for authoring use cases than weak + ETags. Semantic equivalence can be a useful concept but that depends + on the document type and the application type, and interoperability + might require some agreement or standard outside the scope of this + specification and HTTP. Note also that weak ETags have certain + restrictions in HTTP, e.g. these cannot be used in If-Match headers. + + Note that the meaning of an ETag in a PUT response is not clearly + defined either in this document or in RFC2616 (i.e., whether the ETag + means that the resource is octet-for-octet equivalent to the body of + the PUT request, or whether the server could have made minor changes + in the formatting or content of the document upon storage). It is + hoped that future specification work will clarify this confusion. Because clients may be forced to prompt users or throw away changed content if the ETag changes, a WebDAV server SHOULD NOT change the ETag (or the Last-Modified time) for a resource that has an unchanged body and location. The ETag represents the state of the body or contents of the resource. There is no similar way to tell if properties have changed. -8.1.5. Including error response bodies +8.6. Including error response bodies HTTP and WebDAV did not use the bodies of most error responses for machine-parsable information until DeltaV introduced a mechanism to include more specific information in the body of an error response (section 1.6 of [RFC3253]). The error body mechanism is appropriate to use with any error response that may take a body but does not already have a body defined. The mechanism is particularly appropriate when a status code can mean many things (for example, 400 Bad Request can mean required headers are missing, headers are incorrectly formatted, or much more). This error body mechanism is - covered in Section 15 + covered in Section 16 -8.1.6. Impact of Namespace Operations on Cache Validators +8.7. Impact of Namespace Operations on Cache Validators Note that the HTTP response headers "Etag" and "Last-Modified" (see [RFC2616], Sections 14.19 and 14.29) are defined per URL (not per resource), and are used by clients for caching. Therefore servers must ensure that executing any operation that affects the URL namespace (such as COPY, MOVE, DELETE, PUT or MKCOL) does preserve their semantics, in particular: - For any given URL, the "Last-Modified" value MUST increment every + o For any given URL, the "Last-Modified" value MUST increment every time the representation returned upon GET changes (within the limits of timestamp resolution). - For any given URL, an "ETag" value MUST NOT be re-used for + o For any given URL, an "ETag" value MUST NOT be re-used for different representations returned by GET. In practice this means that servers - might have to increment "Last-Modified" timestamps for every + o might have to increment "Last-Modified" timestamps for every resource inside the destination namespace of a namespace operation unless it can do so more selectively, and - similarily, might have to re-assign "ETag" values for these + o similarily, might have to re-assign "ETag" values for these resources (unless the server allocates entity tags in a way so that they are unique across the whole URL namespace managed by the server). Note that these considerations also apply to specific use cases, such as using PUT to create a new resource at a URL that has been mapped before, but has been deleted since then. Finally, WebDAV properties (such as DAV:getetag and DAV: getlastmodified) that inherit their semantics from HTTP headers must behave accordingly. -8.2. PROPFIND Method +9. HTTP Methods for Distributed Authoring + +9.1. PROPFIND Method The PROPFIND method retrieves properties defined on the resource identified by the Request-URI, if the resource does not have any internal members, or on the resource identified by the Request-URI and potentially its member resources, if the resource is a collection that has internal member URLs. All DAV compliant resources MUST support the PROPFIND method and the propfind XML element - (Section 13.19) along with all XML elements defined for use with that + (Section 14.20) 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 "infinity" with a PROPFIND on a collection resource. Servers MUST support "0" and "1" depth requests on WebDAV-compliant resources and - SHOULD support "infinity" requests in the absence of serious - performance issues. By default, the PROPFIND method without a Depth - header MUST act as if a "Depth: infinity" header was included. + SHOULD support "infinity" requests. In practice, support for depth + infinity requests MAY be disabled, due to the performance and + security concerns associated with this behavior. By default, the + PROPFIND method without a Depth header MUST act as if a "Depth: + infinity" header was included. A client may submit a 'propfind' XML element in the body of the request method describing what information is being requested. It is possible to: o Request particular property values, by naming the properties desired within the 'prop' element (the ordering of properties in here MAY be ignored by server), o Request property values for those properties defined in this @@ -1451,111 +1597,112 @@ resource, by using the 'propname' element. A client may choose not to submit a request body. An empty PROPFIND request body MUST be treated as if it were an 'allprop' request. Note that 'allprop' does not return values for all live properties. WebDAV servers increasingly have expensively-calculated or lengthy properties (see [RFC3253] and [RFC3744]) and do not return all properties already. Instead, WebDAV clients can use propname requests to discover what live properties exist, and request named - properties when retrieving values. A WebDAV server MAY omit certain - live properties from other specifications when responding to an - 'allprop' request, and MAY return only custom (dead) properties and - those defined in this specification. + properties when retrieving values. For a live property defined + elsewhere, that definition can specify whether that live property + would be returned in 'allprop' requests or not. All servers MUST support returning a response of content type text/ xml or application/xml that contains a multistatus XML element that describes the results of the attempts to retrieve the various properties. If there is an error retrieving a property then a proper error result MUST be included in the response. A request to retrieve the 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. Consequently, the 'multistatus' XML element for a collection resource with member URLs MUST include a 'response' XML element for each member URL of the collection, to whatever depth was requested. Each 'response' XML element MUST contain an 'href' XML element that contains the URL of the resource on which the properties in the prop XML element are defined. Results for a PROPFIND on a collection resource with internal member URLs are returned as a flat list whose - order of entries is not significant. + order of entries is not significant. Note that a resource may have + only one value for a property of a given name, so the property may + only show up once in PROPFIND responses. Properties may be subject to access control. In the case of 'allprop' and 'propname' requests, if a principal does not have the right to know whether a particular property exists then the property MAY be silently excluded from the response. Some PROPFIND results MAY be cached, with care as there is no cache validation mechanism for most properties. This method is both safe and idempotent (see section 9.1 of [RFC2616]). -8.2.1. PROPFIND status codes +9.1.1. PROPFIND status codes This section, as with similar sections for other methods, provides some guidance on error codes and preconditions or postconditions - (defined in Section 15) that might be particularly useful with + (defined in Section 16) that might be particularly useful with PROPFIND. 403 Forbidden - A server MAY reject PROPFIND requests on collections with depth header of "Infinity", in which case it SHOULD use this error with the precondition code 'propfind-finite-depth' inside the error body. -8.2.2. Status codes for use with 207 (Multi-Status) +9.1.2. Status codes for use with 207 (Multi-Status) The following are examples of response codes one would expect to be used in a 207 (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 207 (Multi-Status) response. 200 OK - A property exists and/or its value is successfully returned. 401 Unauthorized - The property cannot be viewed without appropriate authorization. 403 Forbidden - The property cannot be viewed regardless of authentication. 404 Not Found - The property does not exist. -8.2.3. Example - Retrieving Named Properties +9.1.3. Example - Retrieving Named Properties >>Request PROPFIND /file HTTP/1.1 Host: www.example.com Content-type: application/xml; charset="utf-8" Content-Length: xxxx - + >>Response HTTP/1.1 207 Multi-Status Content-Type: application/xml; charset="utf-8" Content-Length: xxxx - + http://www.example.com/file Box type A J.J. Johnson @@ -1573,21 +1720,21 @@ In this example, PROPFIND is executed on a non-collection resource http://www.example.com/file. The propfind XML element specifies the name of four properties whose values are being requested. In this case only two properties were returned, since the principal issuing the request did not have sufficient access rights to see the third and fourth properties. -8.2.4. Example - Retrieving Named and Dead Properties +9.1.4. Example - Retrieving Named and Dead Properties >>Request PROPFIND /mycol/ HTTP/1.1 Host: www.example.com Depth: 1 Content-type: application/xml; charset="utf-8" Content-Length: xxxx @@ -1597,21 +1744,21 @@ In this example, PROPFIND is executed on a collection resource http://www.example.com/mycol/. The client requests the values of two specific live properties plus all dead properties (names and values). The response is not shown. -8.2.5. Example - Using 'propname' to Retrieve all Property Names +9.1.5. Example - Using 'propname' to Retrieve all Property Names >>Request PROPFIND /container/ HTTP/1.1 Host: www.example.com Content-Type: application/xml; charset="utf-8" Content-Length: xxxx @@ -1621,35 +1768,35 @@ HTTP/1.1 207 Multi-Status Content-Type: application/xml; charset="utf-8" Content-Length: xxxx http://www.example.com/container/ - + HTTP/1.1 200 OK http://www.example.com/container/front.html - + @@ -1661,38 +1808,38 @@ In this example, PROPFIND is invoked on the collection resource http://www.example.com/container/, with a propfind XML element containing the propname XML element, meaning the name of all properties should be returned. Since no Depth header is present, it assumes its default value of "infinity", meaning the name of the properties on the collection and all its descendents should be returned. Consistent with the previous example, resource http://www.example.com/container/ has six properties defined on it: - bigbox and author in the "http://www.example.com/boxschema/" + bigbox and author in the "http://ns.example.com/boxschema/" namespace, and creationdate, displayname, resourcetype, and supportedlock in the "DAV:" namespace. The resource http://www.example.com/container/index.html, a member of the "container" collection, has nine properties defined on it, bigbox - in the "http://www.example.com/boxschema/" namespace and, + in the "http://ns.example.com/boxschema/" namespace and, creationdate, displayname, getcontentlength, getcontenttype, getetag, getlastmodified, resourcetype, and supportedlock in the "DAV:" namespace. This example also demonstrates the use of XML namespace scoping and the default namespace. Since the "xmlns" attribute does not contain a prefix, the namespace applies by default to all enclosed elements. Hence, all elements which do not explicitly state the namespace to which they belong are members of the "DAV:" namespace. -8.2.6. Example - Using 'allprop' +9.1.6. Example - Using 'allprop' Note that 'allprop', despite its name which remains for backward- compatibility, does not return every property, but only dead properties and the live properties defined in this specification. >>Request PROPFIND /container/ HTTP/1.1 Host: www.example.com Depth: 1 @@ -1708,21 +1855,21 @@ HTTP/1.1 207 Multi-Status Content-Type: application/xml; charset="utf-8" Content-Length: xxxx /container/ - + Box type A Hadrian 1997-12-01T17:42:21-08:00 Example collection @@ -1731,21 +1878,21 @@ HTTP/1.1 200 OK /container/front.html - + Box type B 1997-12-01T18:27:21-08:00 Example HTML resource 4525 text/html "zzyzx" Mon, 12 Jan 1998 09:25:56 GMT @@ -1759,61 +1906,61 @@ HTTP/1.1 200 OK In this example, PROPFIND was invoked on the resource - 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 - element containing the allprop XML element, meaning the request + http://www.example.com/container/ with a Depth header of 1, meaning + the request applies to the resource and its children, and a propfind + XML element containing the allprop XML element, meaning the request should return the name and value of all the dead properties defined on the resources, plus the name and value of all the properties defined in this specification. This example illustrates the use of relative references in the 'href' elements of the response. - The resource http://www.foo.bar/container/ has six properties defined - on it: 'bigbox' and 'author in the "http://www.foo.bar/boxschema/" - namespace, DAV:creationdate, DAV:displayname, DAV:resourcetype, and - DAV:supportedlock. + The resource http://www.example.com/container/ has six properties + defined on it: 'bigbox' and 'author in the + "http://ns.example.com/boxschema/" namespace, DAV:creationdate, DAV: + displayname, DAV:resourcetype, and DAV:supportedlock. - The last four properties are WebDAV-specific, defined in Section 14. + The last four properties are WebDAV-specific, defined in Section 15. Since GET is not supported on this resource, the get* properties (e.g., DAV:getcontentlength) are not defined on this resource. The WebDAV-specific properties assert that "container" was created on December 1, 1997, at 5:42:21PM, in a time zone 8 hours west of GMT (DAV:creationdate), has a name of "Example collection" (DAV: displayname), a collection resource type (DAV:resourcetype), and supports exclusive write and shared write locks (DAV:supportedlock). - The resource http://www.foo.bar/container/front.html has nine + The resource http://www.example.com/container/front.html has nine properties defined on it: - 'bigbox' in the "http://www.foo.bar/boxschema/" namespace (another + 'bigbox' in the "http://ns.example.com/boxschema/" namespace (another instance of the "bigbox" property type), DAV:creationdate, DAV: displayname, DAV:getcontentlength, DAV:getcontenttype, DAV:getetag, DAV:getlastmodified, DAV:resourcetype, and DAV:supportedlock. The DAV-specific properties assert that "front.html" was created on December 1, 1997, at 6:27:21PM, in a time zone 8 hours west of GMT (DAV:creationdate), has a name of "Example HTML resource" (DAV: displayname), a content length of 4525 bytes (DAV:getcontentlength), a MIME type of "text/html" (DAV:getcontenttype), an entity tag of "zzyzx" (DAV:getetag), was last modified on Monday, January 12, 1998, at 09:25:56 GMT (DAV:getlastmodified), has an empty resource type, meaning that it is not a collection (DAV:resourcetype), and supports both exclusive write and shared write locks (DAV:supportedlock). -8.3. PROPPATCH Method +9.2. PROPPATCH Method The PROPPATCH method processes instructions specified in the request body to set and/or remove properties defined on the resource identified by the Request-URI. All DAV compliant resources MUST support the PROPPATCH method and MUST process instructions that are specified using the propertyupdate, set, and remove XML elements. Execution of the directives in this method is, of course, subject to access control constraints. DAV compliant resources SHOULD support the setting of @@ -1822,111 +1969,111 @@ The request message body of a PROPPATCH method MUST contain the propertyupdate XML element. Clients SHOULD NOT alter the same property more than once in a single PROPPATCH request. Servers MUST process PROPPATCH instructions in document order (an exception to the normal rule that ordering is irrelevant). Instructions MUST either all be executed or none executed. Thus if any error occurs during processing all executed instructions MUST be undone and a proper error result returned. Instruction processing details can be found in the definition of the set and remove - instructions in Section 13.22 and Section 13.25. + instructions in Section 14.23 and Section 14.26. This method is idempotent, but not safe (see section 9.1 of [RFC2616]). Responses to this method MUST NOT be cached. -8.3.1. Status Codes for use in 207 (Multi-Status) +9.2.1. Status Codes for use in 207 (Multi-Status) The following are examples of response codes one would expect to be used in a 207 (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 207 (Multi-Status) response. 200 (OK) - The property set or change succeeded. Note that if this appears for one property, it appears for every property in the response, due to the atomicity of PROPPATCH. 403 (Forbidden) - The client, for reasons the server chooses not to specify, cannot alter one of the properties. 403 (Forbidden): The client has attempted to set a read-only property, such as DAV:getetag. If returning this error, the server - SHOULD use the precondition code 'writable-property' inside the - response body. + SHOULD use the precondition code 'cannot-modify-protected-property' + inside the response body. 409 (Conflict) - The client has provided a value whose semantics are not appropriate for the property. 424 (Failed Dependency) - The property change could not be made because of another property change that failed. 507 (Insufficient Storage) - The server did not have sufficient space to record the property. -8.3.2. Example - PROPPATCH +9.2.2. Example - PROPPATCH >>Request PROPPATCH /bar.html HTTP/1.1 Host: www.example.com Content-Type: application/xml; charset="utf-8" Content-Length: xxxx + xmlns:Z="http://ns.example.com/standards/z39.50/"> - + Jim Whitehead Roy Fielding - + >>Response HTTP/1.1 207 Multi-Status Content-Type: application/xml; charset="utf-8" Content-Length: xxxx + xmlns:Z="http://ns.example.com/standards/z39.50/"> http://www.example.com/bar.html HTTP/1.1 424 Failed Dependency HTTP/1.1 409 Conflict Copyright Owner can not be deleted or altered. In this example, the client requests the server to set the value of - the "Authors" property in the "http://www.w3.com/standards/z39.50/" - namespace, and to remove the property "Copyright-Owner" in the - "http://www.w3.com/standards/z39.50/" namespace. Since the + the "Authors" property in the + "http://ns.example.com/standards/z39.50/" namespace, and to remove + the property "Copyright-Owner" in the same namespace. Since the Copyright-Owner property could not be removed, no property modifications occur. The 424 (Failed Dependency) status code for the Authors property indicates this action would have succeeded if it were not for the conflict with removing the Copyright-Owner property. -8.4. MKCOL Method +9.3. MKCOL Method The MKCOL method is used to create a new collection. All WebDAV compliant resources MUST support the MKCOL method. MKCOL creates a new collection resource at the location specified by the Request-URI. If the Request-URI is already mapped to a resource then the MKCOL MUST fail. During MKCOL processing, a server MUST make the Request-URI a member of its parent collection, unless the Request-URI is "/". If no such ancestor exists, the method MUST fail. When the MKCOL operation creates a new collection resource, @@ -1944,21 +2091,21 @@ of members and properties on the collections or members. If the server receives a MKCOL request entity type it does not support or understand it MUST respond with a 415 (Unsupported Media Type) status code. If the server decides to reject the request based on the presence of an entity or the type of an entity, it should use the 415 (Unsupported Media Type) status code. This method is idempotent, but not safe (see section 9.1 of [RFC2616]). Responses to this method MUST NOT be cached. -8.4.1. MKCOL Status Codes +9.3.1. MKCOL Status Codes In addition to the general status codes possible, the following status codes have specific applicability to MKCOL: 201 (Created) - The collection was created. 403 (Forbidden) - This indicates at least one of two conditions: 1) the server does not allow the creation of collections at the given location in its URL namespace, or 2) the parent collection of the Request-URI exists but cannot accept members. @@ -1971,74 +2118,74 @@ MUST NOT create those intermediate collections automatically. 415 (Unsupported Media Type) - The server does not support the request body type (since this specification does not define any body for MKCOL requests). 507 (Insufficient Storage) - The resource does not have sufficient space to record the state of the resource after the execution of this method. -8.4.2. Example - MKCOL +9.3.2. Example - MKCOL This example creates a collection called /webdisc/xfiles/ on the server www.example.com. >>Request MKCOL /webdisc/xfiles/ HTTP/1.1 Host: www.example.com >>Response HTTP/1.1 201 Created -8.5. GET, HEAD for Collections +9.4. GET, HEAD for Collections The semantics of GET are unchanged when applied to a collection, since GET is defined as, "retrieve whatever information (in the form of an entity) is identified by the Request-URI" [RFC2616]. GET when applied to a collection may return 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 that the result of a GET on a collection will bear no correlation to the membership of the collection. Similarly, since the definition of HEAD is a GET without a response message body, the semantics of HEAD are unmodified when applied to collection resources. -8.6. POST for Collections +9.5. POST for Collections Since by definition the actual function performed by POST is determined by the server and often depends on the particular resource, the behavior of POST when applied to collections cannot be meaningfully modified because it is largely undefined. Thus the semantics of POST are unmodified when applied to a collection. -8.7. DELETE Requirements +9.6. DELETE Requirements DELETE is defined in [RFC2616], section 9.7, to "delete the resource identified by the Request-URI". However, WebDAV changes some DELETE handling requirements. A server processing a successful DELETE request: MUST destroy locks rooted on the deleted resource MUST remove the mapping from the Request-URI to any resource. Thus, after a successful DELETE operation (and in the absence of other actions) a subsequent GET/HEAD/PROPFIND request to the target Request-URI MUST return 404 (Not Found). -8.7.1. DELETE for Collections +9.6.1. DELETE for Collections 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 with a DELETE on a collection with any value but infinity. DELETE instructs that the collection specified in the Request-URI and all resources identified by its internal member URLs are to be deleted. If any resource identified by a member URL cannot be deleted then all @@ -2063,141 +2210,145 @@ the request failed completely. 424 (Failed Dependency) status codes SHOULD NOT be in the 207 (Multi- Status) response for DELETE. They can be safely left out because the client will know that the ancestors of a resource could not be deleted when the 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. -8.7.2. Example - DELETE +9.6.2. Example - DELETE >>Request DELETE /container/ HTTP/1.1 Host: www.example.com >>Response HTTP/1.1 207 Multi-Status Content-Type: application/xml; charset="utf-8" Content-Length: xxxx http://www.example.com/container/resource3 HTTP/1.1 423 Locked + In this example the attempt to delete http://www.example.com/container/resource3 failed because it is locked, and no lock token was submitted with the request. Consequently, the attempt to delete http://www.example.com/container/ also failed. Thus the client knows that the attempt to delete http://www.example.com/container/ must have also failed since the parent can not be deleted unless its child has also been deleted. Even though a Depth header has not been included, a depth of infinity is assumed because the method is on a collection. -8.8. PUT Requirements +9.7. PUT Requirements -8.8.1. PUT for Non-Collection Resources +9.7.1. PUT for Non-Collection Resources A PUT performed on an existing resource replaces the GET response entity of the resource. Properties defined on the resource may be recomputed during PUT processing but are not otherwise affected. For example, if a server recognizes the content type of the request body, it may be able to automatically extract information that could be profitably exposed as properties. A PUT that would result in the creation of a resource without an appropriately scoped parent collection MUST fail with a 409 (Conflict). A PUT request is the only way a client has to indicate to the server what Content-Type a resource should have, and whether it should change if the resource is overwritten. Thus, a client MUST provide a Content-Type for a new resource if any is known, and a server SHOULD use the Content-Type header value on any PUT request as the resource's type (unless security concerns or policy dictates - otherwise). + otherwise). If the client does not provide a Content-Type for a new + resource, the server MAY create a resource with no Content-Type + assigned, or it MAY attempt to assign a reasonable and legal Content- + Type. Note that although a recipient should treat metadata supplied with an HTTP request as authorative, in practice there's no guarantee that a server will accept Content- headers. Many servers do not allow configuring the Content-Type on a per-resource basis in the first place. Thus, clients should not rely on the ability to directly influence the content type by including a Content-Type request header. -8.8.2. PUT for Collections +9.7.2. PUT for Collections This specification does not define the behavior of the PUT method for existing collections. A PUT request to an existing collection MAY be treated as an error (405 Method Not Allowed). The MKCOL method is defined to create collections. -8.9. COPY Method +9.8. COPY Method The COPY method creates a duplicate of the source resource identified by the Request-URI, in the destination resource identified by the URI in the Destination header. The Destination header MUST be present. The exact behavior of the COPY method depends on the type of the source resource. All WebDAV compliant resources MUST support the COPY method. However, support for the COPY method does not guarantee the ability to copy a resource. For example, separate programs may control 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. This method is idempotent, but not safe (see section 9.1 of [RFC2616]). Responses to this method MUST NOT be cached. -8.9.1. COPY for Non-collection Resources +9.8.1. COPY for Non-collection Resources When the source resource is not a collection the result of the COPY method is the creation of a new resource at the destination whose state and behavior match that of the source resource as closely as possible. Since the environment at the destination may be different than at the source due to factors outside the scope of control of the server, such as the absence of resources required for correct operation, it may not be possible to completely duplicate the behavior of the resource at the destination. Subsequent alterations to the destination resource will not modify the source resource. Subsequent alterations to the source resource will not modify the destination resource. -8.9.2. COPY for Properties +9.8.2. COPY for Properties After a successful COPY invocation, all dead properties on the source resource MUST be duplicated on the destination resource, along with all properties as appropriate. Live properties described in this document SHOULD be duplicated as identically behaving live properties at the destination resource, but not necessarily with the same values. Servers SHOULD NOT convert live properties into dead properties on the destination resource, because clients may then draw incorrect conclusions about the state or functionality of a resource. Note that some live properties are defined such that the absence of the property has a specific meaning (e.g. a flag with one meaning if present and the opposite if absent), and in these cases, a successful COPY might result in the property being reported as "Not Found" in subsequent requests. A COPY operation creates a new resource, much like a PUT operation does. Live properties which are related to resource creation (such as DAV:creationdate) should have their values set accordingly. -8.9.3. COPY for Collections +9.8.3. COPY for Collections 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 submit a Depth header on a COPY on a collection with a value of "0" or "infinity". Servers MUST support the "0" and "infinity" Depth header behaviors on WebDAV-compliant resources. A COPY of depth infinity instructs that the collection resource identified by the Request-URI is to be copied to the location identified by the URI in the Destination header, and all its internal @@ -2247,21 +2398,21 @@ The 424 (Failed Dependency) status code SHOULD NOT be returned in the 207 (Multi-Status) response from a COPY method. These responses can be safely omitted 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) status 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. -8.9.4. COPY and Overwriting Destination Resources +9.8.4. COPY and Overwriting Destination Resources If a COPY request has an Overwrite header with a value of "F", and a resource exists at the Destination URL, the server MUST fail the request. When a server executes a COPY request and overwrites a destination resource, the exact behavior MAY depend on many factors, including WebDAV extension capabilities (see particularly [RFC3253]). For example, when an ordinary resource is overwritten, the server could delete the target resource before doing the copy, or could do an in- @@ -2271,21 +2422,21 @@ collection after the successful COPY request MUST be the same membership as the source collection immediately before the COPY. Thus, merging the membership of the source and destination collections together in the destination is not a compliant behavior. In general, if clients require the state of the destination URL to be wiped out prior to a COPY (e.g. to force live properties to be reset), then the client could send a DELETE to the destination before the COPY request to ensure this reset. -8.9.5. Status Codes +9.8.5. Status Codes In addition to the general status codes possible, the following status codes have specific applicability to COPY: 201 (Created) - The source resource was successfully copied. The COPY operation resulted in the creation of a new resource. 204 (No Content) - The source resource was successfully copied to a pre-existing destination resource. @@ -2304,69 +2455,69 @@ 409 (Conflict) - A resource cannot be created at the destination until one or more intermediate collections have been created. The server MUST NOT create those intermediate collections automatically. 412 (Precondition Failed) - A precondition header check failed, e.g. the Overwrite header is "F" and the destination URL is already mapped to a resource. 423 (Locked) - The destination resource, or resource within the destination collection, was locked. This response SHOULD contain the - 'lock-token-present' precondition element. + 'lock-token-submitted' precondition element. 502 (Bad Gateway) - This may occur when the destination is on another server, repository or URL namespace. Either the source namespace does not support copying to the destination namespace, or the destination namespace refuses to accept the resource. The client may wish to try GET/PUT and PROPFIND/PROPPATCH instead. 507 (Insufficient Storage) - The destination resource does not have sufficient space to record the state of the resource after the execution of this method. -8.9.6. Example - COPY with Overwrite +9.8.6. Example - COPY with Overwrite This example shows resource - http://www.ics.uci.edu/~fielding/index.html being copied to the - location http://www.ics.uci.edu/users/f/fielding/index.html. The 204 + http://www.example.com/~fielding/index.html being copied to the + location http://www.example.com/users/f/fielding/index.html. The 204 (No Content) status code indicates the existing resource at the destination was overwritten. >>Request COPY /~fielding/index.html HTTP/1.1 - Host: www.ics.uci.edu - Destination: http://www.ics.uci.edu/users/f/fielding/index.html + Host: www.example.com + Destination: http://www.example.com/users/f/fielding/index.html >>Response HTTP/1.1 204 No Content -8.9.7. Example - COPY with No Overwrite +9.8.7. Example - COPY with No Overwrite The following example shows the same copy operation being performed, but with the Overwrite header set to "F." A response of 412 (Precondition Failed) is returned because the destination URL is already mapped to a resource. >>Request COPY /~fielding/index.html HTTP/1.1 - Host: www.ics.uci.edu - Destination: http://www.ics.uci.edu/users/f/fielding/index.html + Host: www.example.com + Destination: http://www.example.com/users/f/fielding/index.html Overwrite: F >>Response HTTP/1.1 412 Precondition Failed -8.9.8. Example - COPY of a Collection +9.8.8. Example - COPY of a Collection >>Request COPY /container/ HTTP/1.1 Host: www.example.com Destination: http://www.example.com/othercontainer/ Depth: infinity >>Response @@ -2385,21 +2536,21 @@ 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 submitted. In this example most of the resources, along with the collection, were copied successfully. However the collection R2 failed because the destination R2 is locked. Because there was an error copying R2, none of R2's members were copied. However no errors were listed for those members due to the error minimization rules. -8.10. MOVE Method +9.9. MOVE Method The MOVE operation on a non-collection resource is the logical equivalent of a copy (COPY), followed by consistency maintenance processing, followed by a delete of the source, where all three actions are performed atomically. The consistency maintenance step allows the server to perform updates caused by the move, such as updating all URLs other than the Request-URI which identify the source resource, to point to the new destination resource. Consequently, the Destination header MUST be present on all MOVE methods and MUST follow all COPY requirements for the COPY part of @@ -2412,41 +2563,41 @@ move a resource within a namespace that appears to belong to the same server. If a resource exists at the destination, the destination resource will be deleted as a side-effect of the MOVE operation, subject to the restrictions of the Overwrite header. This method is idempotent, but not safe (see section 9.1 of [RFC2616]). Responses to this method MUST NOT be cached. -8.10.1. MOVE for Properties +9.9.1. MOVE for Properties Live properties described in this document SHOULD be moved along with the resource, such that the resource has identically behaving live properties at the destination resource, but not necessarily with the same values. Note that some live properties are defined such that the absence of the property has a specific meaning (e.g. a flag with one meaning if present and the opposite if absent), and in these cases, a successful MOVE might result in the property being reported as "Not Found" in subsequent requests. If the live properties will not work the same way at the destination, the server MAY fail the request. MOVE is frequently used by clients to rename a file without changing its parent collection, so it's not appropriate to reset all live properties which are set at resource creation. For example, the DAV: creationdate property value SHOULD remain the same after a MOVE. Dead properties MUST be moved along with the resource. -8.10.2. MOVE for Collections +9.9.2. MOVE for Collections A MOVE with "Depth: infinity" instructs that the collection identified by the Request-URI be moved to the address specified in the Destination header, and all resources identified by its internal member URLs are to be moved to locations relative to it, recursively through all levels of the collection hierarchy. 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 MOVE on a collection with any value but "infinity". @@ -2480,28 +2631,28 @@ The 424 (Failed Dependency) status code SHOULD NOT be returned in the 207 (Multi-Status) response from a MOVE method. These errors can be safely omitted because the client will know that the progeny of a resource could not be moved when the client receives an error for the parent. Additionally 201 (Created)/204 (No Content) responses SHOULD NOT be returned as values in 207 (Multi-Status) responses from a MOVE. These responses can be safely omitted because they are the default success codes. -8.10.3. MOVE and the Overwrite Header +9.9.3. MOVE and the Overwrite Header 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. -8.10.4. Status Codes +9.9.4. Status Codes In addition to the general status codes possible, the following status codes have specific applicability to MOVE: 201 (Created) - The source resource was successfully moved, and a new URL mapping was created at the destination. 204 (No Content) - The source resource was successfully moved to a URL that was already mapped. @@ -2524,48 +2675,48 @@ properties and still move the resource to the destination (see 'preserved-live-properties' postcondition). 412 (Precondition Failed) - A condition header failed. Specific to MOVE, this could mean that the Overwrite header is "F" and the state of the destination URL is already mapped to a resource. 423 (Locked) - The source or the destination resource, the source or destination resource parent, or some resource within the source or destination collection, was locked. This response SHOULD contain the - 'lock-token-present' precondition element. + 'lock-token-submitted' precondition element. 502 (Bad Gateway) - This may occur when the destination is on another server and the destination server refuses to accept the resource. This could also occur when the destination is on another sub-section of the same server namespace. -8.10.5. Example - MOVE of a Non-Collection +9.9.5. Example - MOVE of a Non-Collection This example shows resource - http://www.ics.uci.edu/~fielding/index.html being moved to the - location http://www.ics.uci.edu/users/f/fielding/index.html. The + http://www.example.com/~fielding/index.html being moved to the + location http://www.example.com/users/f/fielding/index.html. The contents of the destination resource would have been overwritten if the destination URL was already mapped to a resource. In this case, since there was nothing at the destination resource, the response code is 201 (Created). >>Request MOVE /~fielding/index.html HTTP/1.1 - Host: www.ics.uci.edu - Destination: http://www.ics.uci.edu/users/f/fielding/index.html + Host: www.example.com + Destination: http://www.example/users/f/fielding/index.html >>Response HTTP/1.1 201 Created - Location: http://www.ics.uci.edu/users/f/fielding/index.html + Location: http://www.example.com/users/f/fielding/index.html -8.10.6. Example - MOVE of a Collection +9.9.6. Example - MOVE of a Collection >>Request MOVE /container/ HTTP/1.1 Host: www.example.com Destination: http://www.example.com/othercontainer/ Overwrite: F If: () () @@ -2589,84 +2740,79 @@ method, that is locked. In this case the proper lock token was not submitted for the destination http://www.example.com/othercontainer/C2/. This means that the resource /container/C2/ could not be moved. Because there was an error moving /container/C2/, none of /container/C2's members were moved. However no errors were listed for those members due to the error minimization rules. User agent authentication has previously occurred via a mechanism outside the scope of the HTTP protocol, in an underlying transport layer. -8.11. LOCK Method +9.10. LOCK Method The following sections describe the LOCK method, which is used to take out a lock of any access type and to refresh an existing lock. These sections on 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 requested. Any resource which supports the LOCK method MUST, at minimum, support the XML request and response formats defined herein. - A LOCK method invocation to an unlocked resource creates a lock on - the resource identified by the Request-URI, which becomes the root of - the lock. Lock method requests to create a new lock MUST have a XML - request body which contains an 'owner' XML element and other - information for this lock request. The server MUST preserve the - information provided by the client in the 'owner' field when the lock - information is requested. The LOCK request MAY have a Timeout - header. + This method is neither idempotent nor safe (see section 9.1 of + [RFC2616]). Responses to this method MUST NOT be cached. - Clients MUST assume that locks may arbitrarily disappear at any time, - regardless of the value given in the Timeout header. The Timeout - header only indicates the behavior of the server if extraordinary - circumstances do not occur. For example, a sufficiently privileged - user may remove a lock at any time or the system may crash in such a - way that it loses the record of the lock's existence. +9.10.1. Creating a lock on existing resource + + A LOCK request to an existing resource will create a lock on the + resource identified by the Request-URI, provided the resource is not + already locked with a conflicting lock. The resource identified in + the Request-URI becomes the root of the lock. Lock method requests + to create a new lock MUST have a XML request body. The server MUST + preserve the information provided by the client in the 'owner' field + in the request body when the lock information is requested. The LOCK + request MAY have a Timeout header. When a new lock is created, the LOCK response: o MUST contain a body with the value of the DAV:lockdiscovery property in a prop XML element. This MUST contain the full information about the lock just granted, while information about other (shared) locks is OPTIONAL. o MUST include the Lock-Token response header with the token associated with the new lock. - This method is neither idempotent nor safe (see section 9.1 of - [RFC2616]). Responses to this method MUST NOT be cached. - -8.11.1. Refreshing Locks +9.10.2. Refreshing Locks - A lock is refreshed by sending a LOCK request without a request body - to the URL of a resource within the scope of the lock. This request - MUST specify which lock to refresh by using the 'Lock-Token' header - with a single lock token (only one lock may be refreshed at a time). - It MAY contain a Timeout header, which a server MAY accept to change - the duration remaining on the lock to the new value. A server MUST - ignore the Depth header on a LOCK refresh. + A lock is refreshed by sending a LOCK request to the URL of a + resource within the scope of the lock. This request MUST NOT have a + body and it MUST specify which lock to refresh by using the 'Lock- + Token' header with a single lock token (only one lock may be + refreshed at a time). It MAY contain a Timeout header, which a + server MAY accept to change the duration remaining on the lock to the + new value. A server MUST ignore the Depth header on a LOCK refresh. If the resource has other (shared) locks, those locks are unaffected by a lock refresh. Additionally, those locks do not prevent the named lock from being refreshed. Note that in RFC2518, clients were indicated through the example in the text to use the If header to specify what lock to refresh (rather than the Lock-Token header). Servers are encouraged to continue to support this as well as the Lock-Token header. Note that the Lock-Token header is not be returned in the response for a successful refresh LOCK request, but the LOCK response body MUST contain the new value for the DAV:lockdiscovery body. -8.11.2. Depth and Locking +9.10.3. Depth and Locking The Depth header may be used with the LOCK method. Values other 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 by the Request-URI. If the Depth header is set to infinity then the resource specified in @@ -2683,33 +2829,33 @@ one resource which prevented the lock from being granted, along with a suitable status code for that failure (e.g. 403 (Forbidden) or 423 (Locked)). Additionally, if the resource causing the failure was not the resource requested, then the server SHOULD include a 'response' element for the Request-URI as well, with a 'status' element containing 424 Failed Dependency. If no Depth header is submitted on a LOCK request then the request MUST act as if a "Depth:infinity" had been submitted. -8.11.3. Locking Unmapped URLs +9.10.4. Locking Unmapped URLs A successful LOCK method MUST result in the creation of an empty resource which is locked (and which is not a collection), when a resource did not previously exist at that URL. Later on, the lock may go away but the empty resource remains. Empty resources MUST then appear in PROPFIND responses including that URL in the response scope. A server MUST respond successfully to a GET request to an empty resource, either by using a 204 No Content response, or by using 200 OK with a Content-Length header indicating zero length and no Content-Type. -8.11.4. Lock Compatibility Table +9.10.5. Lock Compatibility Table The table below describes the behavior that occurs when a lock request is made on a resource. +--------------------------+----------------+-------------------+ | Current State | Shared Lock OK | Exclusive Lock OK | +--------------------------+----------------+-------------------+ | None | True | True | | | | | | Shared Lock | True | False | @@ -2721,21 +2867,21 @@ granted. *=It is illegal for a principal to request the same lock twice. The current lock state of a resource is given in the leftmost column, and lock requests are listed in the first row. The 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 exclusive lock is requested, the table entry is "false", indicating the lock must not be granted. -8.11.5. LOCK Responses +9.10.6. LOCK Responses In addition to the general status codes possible, the following status codes have specific applicability to LOCK: 200 (OK) - The LOCK request succeeded and the value of the DAV: lockdiscovery property is included in the response body. 201 (Created) - The LOCK request was to an unmapped URL, the request succeeded and resulted in the creation of a new resource, and the value of the DAV:lockdiscovery property is included in the response @@ -2751,82 +2897,82 @@ above). 400 (Bad Request), with 'lock-token-matches-request-uri' precondition code - The LOCK request was made with a Lock-Token header, indicating that the client wishes to refresh the given lock. However, the Request-URI did not fall within the scope of the lock identified by the token. The lock may have a scope that does not include the Request-URI, or the lock could have disappeared, or the token may be invalid. -8.11.6. Example - Simple Lock Request +9.10.7. Example - Simple Lock Request >>Request LOCK /workspace/webdav/proposal.doc HTTP/1.1 Host: example.com Timeout: Infinite, Second-4100000000 Content-Type: application/xml; charset="utf-8" Content-Length: xxxx Authorization: Digest username="ejw", realm="ejw@example.com", nonce="...", uri="/workspace/webdav/proposal.doc", response="...", opaque="..." - http://www.ics.uci.edu/~ejw/contact.html + http://example.org/~ejw/contact.html >>Response HTTP/1.1 200 OK Lock-Token: Content-Type: application/xml; charset="utf-8" Content-Length: xxxx infinity - http://www.ics.uci.edu/~ejw/contact.html + http://example.org/~ejw/contact.html Second-604800 urn:uuid:e71d4fae-5dec-22d6-fea5-00a0c91e6be4 http://example.com/workspace/webdav/proposal.doc This example shows the successful creation of an exclusive write lock on resource http://example.com/workspace/webdav/proposal.doc. The - resource http://www.ics.uci.edu/~ejw/contact.html contains contact + resource http://example.org/~ejw/contact.html contains contact information for the creator of the lock. The server has an activity- based timeout policy in place on this resource, which causes the lock to automatically be removed after 1 week (604800 seconds). Note that the nonce, response, and opaque fields have not been calculated in the Authorization request header. -8.11.7. Example - Refreshing a Write Lock +9.10.8. Example - Refreshing a Write Lock >>Request LOCK /workspace/webdav/proposal.doc HTTP/1.1 Host: example.com Timeout: Infinite, Second-4100000000 Lock-Token: Authorization: Digest username="ejw", realm="ejw@example.com", nonce="...", uri="/workspace/webdav/proposal.doc", @@ -2839,62 +2985,62 @@ Content-Length: xxxx infinity - http://www.ics.uci.edu/~ejw/contact.html + http://example.org/~ejw/contact.html Second-604800 urn:uuid:e71d4fae-5dec-22d6-fea5-00a0c91e6be4 http://example.com/workspace/webdav/proposal.doc This request would refresh the lock, attempting to reset the timeout to the new value specified in the timeout header. Notice that the client asked for an infinite time out but the server choose to ignore the request. In this example, the nonce, response, and opaque fields have not been calculated in the Authorization request header. -8.11.8. Example - Multi-Resource Lock Request +9.10.9. Example - Multi-Resource Lock Request >>Request LOCK /webdav/ HTTP/1.1 Host: example.com Timeout: Infinite, Second-4100000000 Depth: infinity Content-Type: application/xml; charset="utf-8" Content-Length: xxxx Authorization: Digest username="ejw", realm="ejw@example.com", nonce="...", uri="/workspace/webdav/proposal.doc", response="...", opaque="..." - http://www.ics.uci.edu/~ejw/contact.html + http://example.org/~ejw/contact.html >>Response HTTP/1.1 207 Multi-Status Content-Type: application/xml; charset="utf-8" Content-Length: xxxx @@ -2918,21 +3064,21 @@ The error is a 403 (Forbidden) response on the resource http://example.com/webdav/secret. Because this resource could not be locked, none of the resources were locked. Note also that the a 'response' element for the Request-URI itself has been included as required. In this example, the nonce, response, and opaque fields have not been calculated in the Authorization request header. -8.12. UNLOCK Method +9.11. UNLOCK Method The UNLOCK method removes the lock identified by the lock token in the Lock-Token request header. The Request-URI MUST identify a resource within the scope of the lock. Note that use of Lock-Token header to provide the lock token is not consistent with other state-changing methods which all require an If header with the lock token. Thus, the If header is not needed to provide the lock token. Naturally when the If header is present it has its normal meaning as a conditional header. @@ -2947,40 +3093,40 @@ A successful response to an UNLOCK method does not mean that the resource is necessarily unlocked. It means that the specific lock corresponding to the specified token no longer exists. Any DAV compliant resource which supports the LOCK method MUST support the UNLOCK method. This method is idempotent, but not safe (see section 9.1 of [RFC2616]). Responses to this method MUST NOT be cached. -8.12.1. Status Codes +9.11.1. Status Codes In addition to the general status codes possible, the following status codes have specific applicability to UNLOCK: 204 (No Content) - Normal success response (rather than 200 OK, since 200 OK would imply a response body, and an UNLOCK success response does not normally contain a body) 400 (Bad Request) - No lock token was provided (see 'lock-token- - present' precondition), or request was made to a Request-URI that was - not within the scope of the lock (see 'lock-token-matches-request- - uri' precondition). + submitted' precondition), or request was made to a Request-URI that + was not within the scope of the lock (see 'lock-token-matches- + request-uri' precondition). 403 (Forbidden) - The currently authenticated principal does not have permission to remove the lock. 409 (Conflict) - The resource was not locked and thus could not be unlocked. -8.12.2. Example - UNLOCK +9.11.2. Example - UNLOCK >>Request UNLOCK /workspace/webdav/info.doc HTTP/1.1 Host: example.com Lock-Token: Authorization: Digest username="ejw" realm="ejw@example.com", nonce="...", uri="/workspace/webdav/proposal.doc", response="...", opaque="..." @@ -2993,67 +3139,70 @@ "urn:uuid:a515cfa4-5da4-22e1-f5b5-00a0451e6bf7" is successfully removed from the resource http://example.com/workspace/webdav/info.doc. If this lock included more than just one resource, the lock is removed from all resources included in the lock. The 204 (No Content) status code is used instead of 200 (OK) because there is no response entity body. In this example, the nonce, response, and opaque fields have not been calculated in the Authorization request header. -9. HTTP Headers for Distributed Authoring +10. HTTP Headers for Distributed Authoring All DAV headers follow the same basic formatting rules as HTTP headers. This includes rules like line continuation and how to combine (or separate) multiple instances of the same header using commas. WebDAV adds two new conditional headers to the set defined in HTTP: the If and Overwrite headers. -9.1. DAV Header +10.1. DAV Header DAV = "DAV" ":" #( compliance-class ) - compliance-class = ( "1" | "2" | "bis" | extend ) + compliance-class = ( "1" | "2" | "3" | extend ) extend = Coded-URL | token Coded-URL = "<" absolute-URI ">" ; No LWS allowed in Coded-URL ; absolute-URI is defined in RFC3986 This general-header appearing in the response indicates that the resource supports the DAV schema and protocol as specified. All DAV compliant resources MUST return the DAV header with compliance-class "1" on all OPTIONS responses. In cases where WebDAV is only supported in part of the server namespace, an OPTIONS request to non- WebDAV resources (including "/") SHOULD NOT advertise WebDAV support. The value is a comma-separated list of all compliance class identifiers that the resource supports. Class identifiers may be Coded-URLs or tokens (as defined by [RFC2616]). Identifiers can appear in any order. Identifiers that are standardized through the IETF RFC process are tokens, but other identifiers SHOULD be Coded- URLs to encourage uniqueness. - A resource must show class 1 compliance if it shows class 2 or "bis" + A resource must show class 1 compliance if it shows class 2 or 3 compliance. In general, support for one compliance class does not - entail support for any other. Please refer to Section 17 for more - details on compliance classes defined in this specification. + entail support for any other, and in particular, support for + compliance class 3 does not require support for compliance class 2. + Please refer to Section 18 for more details on compliance classes + defined in this specification. Note that many WebDAV servers do not advertise WebDAV support in response to "OPTIONS *". As a request header, this header allows the client to advertise compliance with named features when the server needs that information. Clients SHOULD NOT send this header unless a standards track specification requires it. Any extension that makes use of this as a request header will need to carefully consider caching implications. -9.2. Depth Header +10.2. Depth Header + Depth = "Depth" ":" ("0" | "1" | "infinity") The Depth request header is used with methods executed on resources which could potentially have internal members to indicate whether the method is to be applied only to the resource ("Depth: 0"), to the resource and its immediate children, ("Depth: 1"), or the resource and all its progeny ("Depth: infinity"). The Depth header is only supported if a method's definition explicitly provides for such support. @@ -3094,108 +3243,109 @@ regards to internal children. If a resource does not have internal children then the Depth header MUST be ignored. 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. Thus submitting a "Depth: 1" on a COPY, even if the resource does not have internal members, will result in a 400 (Bad Request). The method should fail not because the resource doesn't have internal members, but because of the illegal value in the header. -9.3. Destination Header - - Destination = "Destination" ":" ( absolute-URI ) +10.3. Destination Header The Destination request header specifies the URI which identifies a destination resource for methods such as COPY and MOVE, which take - two URIs as parameters. Note that the absolute-URI production is - defined in [RFC3986]. + two URIs as parameters. - Since the Destination value is an absolute URI, it may name a - different server (or different port or scheme). If the source server - cannot attempt a copy to the remote server, it MUST fail the request - with a 502 (Bad Gateway) response. + Destination = "Destination" ":" ( Simple-ref ) + + If the Destination value is an absolute URI, it may name a different + server (or different port or scheme). If the source server cannot + attempt a copy to the remote server, it MUST fail the request with a + 502 (Bad Gateway) response. If the Destination value is too long or otherwise unacceptable, the server SHOULD return 400 (Bad Request), ideally with helpful information in an error body. -9.4. If Header +10.4. If Header If = "If" ":" ( 1*No-tag-list | 1*Tagged-list) No-tag-list = List Tagged-list = Resource 1*List - Resource = Coded-URL + Resource = Coded-Reference List = "(" 1*(["Not"](State-token | "[" entity-tag "]")) ")" ; No LWS allowed between "[", entity-tag and "]" State-token = Coded-URL + Coded-Reference = "<" Simple-ref ">" + ; No LWS allowed in Coded-Reference The If request header is intended to have similar functionality to the If-Match header defined in section 14.24 of [RFC2616]. However the If header is intended for use with any URI which represents state information, referred to as a state token, about a resource as well as ETags. A typical example of a state token is a lock token, and lock tokens are the only state tokens defined in this specification. The state token is an example of a state token that will never match an actual valid lock token (not that it's special in - this regard). The purpose of this is described in Section 9.4.4. + this regard). The purpose of this is described in Section 10.4.4. The If header's purpose is to describe a series of state lists. If 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. The server MUST do authorization checks before checking this or any conditional header. Assuming no other errors, the server MUST parse the If header when it appears on any request, evaluate all the clauses, and if the conditional evaluates to false, fail as described above. -9.4.1. No-tag-list Production +10.4.1. No-tag-list Production The No-tag-list production describes a series of state tokens and ETags. If multiple No-tag-list productions are used then one only needs to match the state of the resource for the method to be allowed to continue. All untagged tokens apply to the resource identified in the Request-URI. Example - no-tag-list production If: ( ["I am an ETag"]) (["I am another ETag"]) The previous header would require that the resource identified in the Request-URI be locked with the specified lock token and in the state identified by the "I am an ETag" ETag or in the state identified by the second ETag "I am another ETag". To put the matter more plainly one can think of the previous If header as being in the form (or (and ["I am an ETag"]) (and ["I am another ETag"])). -9.4.2. Tagged-list Production +10.4.2. Tagged-list Production The tagged-list production may be used instead of the no-tag-list production, in order to scope each token to a specific resource. That is, it 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. All clauses must be evaluated. If the state of the resource named in the tag does not match any of the associated state lists then the request MUST fail with a 412 (Precondition Failed). The same URI MUST NOT appear more than once in a resource production in an If header. -9.4.3. Example - Tagged List If header in COPY +10.4.3. Example - Tagged List If header in COPY >>Request COPY /resource1 HTTP/1.1 Host: www.example.com Destination: http://www.example.com/resource2 If: ( [W/"A weak ETag"]) (["strong ETag"]) @@ -3208,45 +3358,50 @@ weak ETag"]) (["strong ETag"])", that is, it either must be locked with a lock token of "urn:uuid:181d4fae-7d8c-11d0-a765-00a0c91e6bf2" and have a weak entity tag W/"A weak ETag" or it must have a strong entity tag "strong ETag". That is the only success condition since the resource http://www.example.com/random never has the method applied to it (the only other resource listed in the If header) and http://www.example.com/resource2 is not listed in the If header. -9.4.4. Not Production +10.4.4. Not Production Every state token or ETag 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 ETag 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 entity-tag immediately following it. If: (Not ) When submitted with a request, this If header requires that all operand resources must not be locked with urn:uuid:181d4fae-7d8c-11d0-a765-00a0c91e6bf2 and must be locked with urn:uuid:58f202ac-22cf-11d1-b12d-002035b29092. - The Not production is particularly useful with a state token known - not to ever identify a lock, such as the "" state token. - The clause "Not " MUST evaluate to true. Thus, any "OR" - statement containing the clause "Not " MUST also - evaluate to true. + The Not production is particularly useful with a state token that + never identifies a lock, such as the "" state token. + The server MUST evaluate any unrecognized state token as false. -9.4.5. Matching Function + Thus, for example: + + The clause "Not " evaluates to true. + + Any "OR" statement containing the clause "Not " + evaluates to true. + +10.4.5. Matching Function When performing If header processing, the definition of a matching state token or entity tag is as follows. Identifying a resource: The resource is identified by the URI along with the token, in tagged list production, or by the Request-URI in untagged list production. Matching entity tag: Where the entity tag matches an entity tag associated with the identified resource. @@ -3267,44 +3422,44 @@ resource, which is the 'specs' collection identified by the URL in the tagged list production. If the 'specs' collection is not locked or has a lock with a different token, the request MUST fail. If the 'specs' collection is locked (depth infinity) with that lock token, then this request could succeed, both because the If header evaluates to true, and because the lock token for the lock affecting the affected resource has been provided. Alternatively, a request where the 'rfc2518.txt' URL is associated with the lock token in the If header could also succeed. -9.4.6. If Header and Non-DAV Aware Proxies +10.4.6. If Header and Non-DAV Aware Proxies Non-DAV aware 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. -9.5. Lock-Token Header +10.5. Lock-Token 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. The Lock-Token response header is used with the LOCK method to indicate the lock token created as a result of a successful LOCK request to create a new lock. -9.6. Overwrite Header +10.6. Overwrite Header Overwrite = "Overwrite" ":" ("T" | "F") The Overwrite request header specifies whether the server should overwrite a resource mapped to the destination URL during a COPY or MOVE. A value of "F" states that the server must not perform the COPY or MOVE operation if the state of the destination URL does map to a resource. If the overwrite header is not included in a COPY or MOVE request then the resource MUST treat the request as if it has an overwrite header of value "T". While the Overwrite header appears to @@ -3312,21 +3467,21 @@ If-Match 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 header, the method MUST fail with a 412 (Precondition Failed) status code. The server MUST do authorization checks before checking this or any conditional header. All DAV compliant resources MUST support the Overwrite header. -9.7. Timeout Request Header +10.7. Timeout Request Header TimeOut = "Timeout" ":" 1#TimeType TimeType = ("Second-" DAVTimeOutVal | "Infinite") ; No LWS allowed within TimeType DAVTimeOutVal = 1*DIGIT Clients may include Timeout request headers in their LOCK requests. However, the server is not required to honor or even consider these requests. Clients MUST NOT submit a Timeout request header with any method other than a LOCK method. @@ -3359,428 +3514,430 @@ ask for a relatively small timeout value so that if the applet dies, the lock can be quickly harvested. However, a document management system is likely to ask for an extremely long timeout 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. Likewise, a client MUST NOT assume that just because the time-out has not expired, the lock still exists (and for this reason, clients are strongly advised to use ETags as well). -10. Status Code Extensions to HTTP/1.1 +11. Status Code Extensions to HTTP/1.1 The following status codes are added to those defined in HTTP/1.1 [RFC2616]. -10.1. 207 Multi-Status +11.1. 207 Multi-Status The 207 (Multi-Status) status code provides status for multiple - independent operations (see Section 12 for more information). + independent operations (see Section 13 for more information). -10.2. 422 Unprocessable Entity +11.2. 422 Unprocessable Entity The 422 (Unprocessable Entity) status code means the server understands the content type of the request entity (hence a 415(Unsupported Media Type) status code is inappropriate), and the syntax of the request entity is correct (thus a 400 (Bad Request) status code is inappropriate) but was unable to process the contained instructions. For example, this error condition may occur if an XML request body contains well-formed (i.e., syntactically correct), but semantically erroneous XML instructions. -10.3. 423 Locked +11.3. 423 Locked The 423 (Locked) status code means the source or destination resource of a method is locked. This response SHOULD contain an appropriate - precondition or postcondition code, such as 'lock-token-present' or + precondition or postcondition code, such as 'lock-token-submitted' or 'no-conflicting-lock". -10.4. 424 Failed Dependency +11.4. 424 Failed Dependency The 424 (Failed Dependency) status code means that the method could not be performed on the resource because the requested action depended on another action and that action failed. For example, if a command in a PROPPATCH method fails then, at minimum, the rest of the commands will also fail with 424 (Failed Dependency). -10.5. 507 Insufficient Storage +11.5. 507 Insufficient Storage The 507 (Insufficient Storage) status code means the method could not be performed on the resource because the server is unable to store the representation needed to successfully complete the request. This condition is considered to be temporary. If the request which received this status code was the result of a user action, the request MUST NOT be repeated until it is requested by a separate user action. -11. Use of HTTP Status Codes +12. Use of HTTP Status Codes These HTTP codes are not redefined, but their use is somewhat extended by WebDAV methods and requirements. In general, many HTTP status codes can be used in response to any request, not just in cases described in this document. Note also that WebDAV servers are known to use 300-level redirect responses (and early interoperability tests found clients unprepared to see those responses). A 300-level request MUST NOT be used when the server has created a new resource in response to the request. -11.1. 412 Precondition Failed +12.1. 412 Precondition Failed Any request can contain a conditional header defined in HTTP (If- Match, If-Modified-Since, etc.) or the "If" or "Overwrite" conditional headers defined in this specification. If the server evaluates a conditional header, and if that condition fails to hold, then this error code MUST be returned. On the other hand, if the client did not include a conditional header in the request, then the server MUST NOT use this error. -11.2. 414 Request-URI Too Long +12.2. 414 Request-URI Too Long This status code is used in HTTP 1.1 only for Request-URIs, not URIs in other locations. -12. Multi-Status Response +13. Multi-Status Response A Multi-Status response contains one 'response' element for each resource in the scope of the request (in no required order) or MAY be empty if no resources match the request. The default 207 (Multi- Status) response body is a text/xml or application/xml HTTP entity that contains a single XML element called 'multistatus', which contains a set of XML elements called response which contain 200, 300, 400, and 500 series status codes generated during the method invocation. 100 series status codes SHOULD NOT be recorded in a 'response' XML element. The 207 status code itself MUST NOT be considered a success response, it is only completely successful if all 'response' elements inside contain success status codes. The body of a 207 Multi-Status response MUST contain a URL associated with each specific status code, so that the client can tell whether the error occurred with the source resource, destination resource or some other resource in the scope of the request. -12.1. Response headers +13.1. Response headers HTTP defines the Location header to indicate a preferred URL for the resource that was addressed in the Request-URI (e.g. in response to successful PUT requests or in redirect responses). However, use of this header creates ambiguity when there are URLs in the body of the response, as with Multi-Status. Thus, use of the Location header with the Multi-Status response is intentionally undefined. -12.2. URL Handling - - A Multi-Status body contains one or more 'response' elements. Each - response element describes a resource, and has an 'href' element - identifying the resource. The 'href' element MUST contain an - absolute URI or relative reference. It MUST NOT include "." or ".." - as path elements. - - If a 'href' element contains a relative reference, it MUST be - resolved against the Request-URI. A relative reference MUST be an - absolute path (note that clients are not known to support relative - paths). - - Identifiers for collections appearing in the results SHOULD end in a - '/' character. - - If a server allows resource names to include characters that aren't - legal in HTTP URL paths, these characters must be percent-encoded on - the wire (see [RFC3986], section 2.1). For example, it is illegal to - use a space character or double-quote in a URI. URIs appearing in - PROPFIND or PROPPATCH XML bodies (or other XML marshalling defined in - this specification) are still subject to all URI rules, including - forbidden characters. - -12.3. Handling redirected child resources +13.2. Handling redirected child resources Redirect responses (300-303, 305 and 307) defined in HTTP 1.1 normally take a Location header to indicate the new URI for the single resource redirected from the Request-URI. Multi-Status responses contain many resource addresses, but the original definition in RFC2518 did not have any place for the server to provide the new URI for redirected resources. This specification does define a 'location' element for this information (see - Section 13.9). Servers MUST use this new element with redirect + Section 14.9). Servers MUST use this new element with redirect responses in Multi-Status. Clients encountering redirected resources in Multi-Status MUST NOT rely on the 'location' element being present with a new URI. If the element is not present, the client MAY reissue the request to the individual redirected resource, because the response to that request can be redirected with a Location header containing the new URI. -12.4. Internal Status Codes +13.3. Internal Status Codes - Section 8.3.1, Section 8.2.2, Section 8.7.1, Section 8.9.3 and - Section 8.10.2 define various status codes used in Multi-Status + Section 9.2.1, Section 9.1.2, Section 9.6.1, Section 9.8.3 and + Section 9.9.2 define various status codes used in Multi-Status responses. This specification does not define the meaning of other status codes that could appear in these responses. -13. XML Element Definitions +14. XML Element Definitions In this section, the final line of each section gives the element type declaration using the format defined in [XML]. The "Value" field, where present, specifies further restrictions on the allowable contents of the XML element using BNF (i.e., to further restrict the values of a PCDATA element). The "Extensibility" field discusses how the element may be extended in the future (or in existing extensions to WebDAV. All of the elements defined here may be extended by the addition of attributes and child elements not defined in this specification. All elements defined here are in the "DAV:" namespace. -13.1. activelock XML Element +14.1. activelock XML Element Name: activelock Purpose: Describes a lock on a resource. -13.2. allprop XML Element +14.2. allprop XML Element Name: allprop Purpose: Specifies that all names and values of dead properties and the live properties defined by this document existing on the resource are to be returned. -13.3. collection XML Element +14.3. collection XML Element Name: collection Purpose: Identifies the associated resource as a collection. The DAV:resourcetype property of a collection resource MUST contain this element. It is normally empty but extensions may add sub- elements. -13.4. depth XML Element +14.4. depth XML Element Name: depth Purpose: The value of the Depth header. Value: "0" | "1" | "infinity" -13.5. error XML Element +14.5. error XML Element Name: error Purpose: Error responses, particularly 403 Forbidden and 409 Conflict, sometimes need more information to indicate what went wrong. When an error response contains a body in WebDAV, the body is in XML with the root element 'error'. The 'error' element SHOULD include an XML element with the code of a failed precondition or postcondition. Description: Contains at least one XML element, and MUST NOT contain text or mixed content. Any element that is a child of the 'error' element is considered to be a precondition or postcondition code. - Unrecognized elements SHOULD be ignored if not recognized. + Unrecognized elements SHOULD be ignored. -13.6. exclusive XML Element +14.6. exclusive XML Element Name: exclusive Purpose: Specifies an exclusive lock -13.7. href XML Element +14.7. href XML Element Name: href - Purpose: Identifies the content of the element as a URI or a - relative reference. There may be limits on the value of 'href' - depending on the context of its use. Refer to the specification - text where 'href' is used to see what limitations apply in each - case. + Purpose: MUST contain a URI or a relative reference. - Value: URI-reference (See section 4.1 of [RFC3986]) + Description: There may be limits on the value of 'href' depending on + the context of its use. Refer to the specification text where + 'href' is used to see what limitations apply in each case. + + Value: Simple-ref -13.8. include XML Element +14.8. include XML Element Name: include Purpose: Any child element represents the name of a property to be included in the PROPFIND response. All elements inside an 'include' XML element MUST define properties related to the resource, although possible property names are in no way limited to those property names defined in this document or other standards. This element MUST NOT contain text or mixed content. -13.9. location XML Element +14.9. location XML Element Name: location Purpose: HTTP defines the "Location" header (see [RFC2616], section 14.30) for use with some status codes (such as 201 and the 300 series codes). When these codes are used inside a 'multistatus' element, the 'location' element can be used to provide the accompanying Location header value. Description: Contains a single href element with the same value that would be used in a Location header. -13.10. lockentry XML Element +14.10. lockentry XML Element Name: lockentry Purpose: Defines the types of locks that can be used with the resource. -13.11. lockinfo XML Element +14.11. lockinfo XML Element Name: lockinfo Purpose: The 'lockinfo' XML element is used with a LOCK method to specify the type of lock the client wishes to have created. -13.12. lockroot XML Element +14.12. lockroot XML Element Name: lockroot Purpose: Contains the root URL of the lock, which is the URL through which the resource was addressed in the LOCK request. Description: The href contains a HTTP URL with the address of the root of the lock. The server SHOULD include this in all DAV: lockdiscovery property values and the response to LOCK requests. -13.13. lockscope XML Element +14.13. lockscope XML Element Name: lockscope Purpose: Specifies whether a lock is an exclusive lock, or a shared lock. -13.14. locktoken XML Element +14.14. locktoken XML Element Name: locktoken Purpose: The lock token associated with a lock. Description: The href contains a single lock token URI which refers to the lock. -13.15. locktype XML Element +14.15. locktype XML Element Name: locktype Purpose: Specifies the access type of a lock. At present, this specification only defines one lock type, the write lock. -13.16. multistatus XML Element +14.16. multistatus XML Element Name: multistatus Purpose: Contains multiple response messages. Description: The 'responsedescription' element at the top level is used to provide a general message describing the overarching nature of the response. If this value is available an application may use it instead of presenting the individual response descriptions contained within the responses. -13.17. prop XML element +14.17. owner XML Element + + Name: owner + + Purpose: Provides information about the creator of a lock. + + Description: Allows a client to provide information sufficient for + either directly contacting a principal (such as a telephone number + or Email URI), or for discovering the principal (such as the URL + of a homepage) who created a lock. The value provided MUST be + treated as a dead property in terms of XML Information Item + preservation. The server MUST NOT alter the value unless the + owner value provided by the client is empty. For a certain amount + of interoperability between different client implementations, if + clients have URI-formatted contact information for the lock + creator suitable for user display, then clients SHOULD put those + URIs in 'href' child elements of the 'owner' element. + + Extensibility: MAY be extended with child elements, mixed content, + text content or attributes. + + + +14.18. prop XML element Name: prop Purpose: Contains properties related to a resource. Description: A generic container for properties defined on resources. All elements inside a 'prop' XML element MUST define properties related to the resource, although possible property names are in no way limited to those property names defined in this document or other standards. This element MUST NOT contain text or mixed content. -13.18. propertyupdate XML element +14.19. propertyupdate XML element Name: propertyupdate Purpose: Contains a request to alter the properties on a resource. Description: This XML element is a container for the information required to modify the properties on the resource. This XML element is multi-valued. -13.19. propfind XML Element +14.20. propfind XML Element Name: propfind Purpose: Specifies the properties to be returned from a PROPFIND method. Four special elements are specified for use with 'propfind': 'prop', 'allprop', 'include' and 'propname'. If 'prop' is used inside 'propfind' it MUST NOT contain property values. -13.20. propname XML Element +14.21. propname XML Element Name: propname Purpose: Specifies that only a list of property names on the resource is to be returned. -13.21. propstat XML Element +14.22. propstat XML Element Name: propstat Purpose: Groups together a prop and status element that is associated with a particular 'href' element. Description: The propstat XML element MUST contain one prop XML element and one status XML element. The contents of the prop XML element MUST only list the names of properties to which the result - in the status element applies. + in the status element applies. The optional precondition/ + postcondition error code and 'responsedescription' text also apply + to the properties named in 'prop'. - + -13.22. remove XML element +14.23. remove XML element Name: remove + Purpose: Lists the DAV properties to be removed from a resource. Description: Remove instructs that the properties specified in prop should be removed. Specifying the removal of a property that does not exist is not an error. All the XML elements in a 'prop' XML element inside of a 'remove' XML element MUST be empty, as only the names of properties to be removed are required. @@ -3777,136 +3934,138 @@ Purpose: Lists the DAV properties to be removed from a resource. Description: Remove instructs that the properties specified in prop should be removed. Specifying the removal of a property that does not exist is not an error. All the XML elements in a 'prop' XML element inside of a 'remove' XML element MUST be empty, as only the names of properties to be removed are required. -13.23. response XML Element +14.24. response XML Element Name: response Purpose: Holds a single response describing the effect of a method on resource and/or its properties. Description: The 'href' element contains a HTTP URL pointing to a WebDAV resource when used in the 'response' container. A particular 'href' value MUST NOT appear more than once as the child of a 'response' XML element under a 'multistatus' XML element. This requirement is necessary in order to keep processing costs for a response to linear time. Essentially, this prevents having to search in order to group together all the responses by 'href'. There are, however, no requirements - regarding ordering based on 'href' values. + regarding ordering based on 'href' values. The optional + precondition/postcondition error code and 'responsedescription' + text can provide additional information about this resource + relative to the request or result. + error?, responsedescription? , location?) > -13.24. responsedescription XML Element +14.25. responsedescription XML Element Name: responsedescription Purpose: Contains information about a status response within a Multi-Status. - Description: Provides information suitable to be presented to a user - (PCDATA) and/or condition name elements (in 'error'). + Description: Provides information suitable to be presented to a + user. - + + +14.26. set XML element -13.25. set XML element Name: set Purpose: Lists the DAV property values to be set for a resource. Description: The 'set' XML element MUST contain only a prop XML element. The elements contained by the prop XML element inside the 'set' XML element MUST specify the name and value of properties that are set on the resource identified by Request-URI. If a property already exists then its value is replaced. Language tagging information appearing in the scope of the 'prop' element (in the "xml:lang" attribute, if present) MUST be persistently stored along with the property, and MUST be subsequently retrievable using PROPFIND. -13.26. shared XML Element +14.27. shared XML Element Name: shared Purpose: Specifies a shared lock -13.27. status XML Element +14.28. status XML Element Name: status Purpose: Holds a single HTTP status-line Value: status-line (status-line defined in Section 6.1 of [RFC2616]) -13.28. timeout XML Element +14.29. timeout XML Element Name: timeout Purpose: The number of seconds remaining before a lock expires. - Value: TimeType (defined in Section 9.7). + Value: TimeType (defined in Section 10.7). -13.29. write XML Element +14.30. write XML Element Name: write Purpose: Specifies a write lock. -14. DAV Properties +15. DAV Properties For DAV properties, the name of the property is also the same as the name of the XML element that contains its value. In the section below, the final line of each section gives the element type declaration using the format defined in [XML]. The "Value" field, where present, specifies further restrictions on the allowable contents of the XML element using BNF (i.e., to further restrict the - values of a PCDATA element). Note that a resource may have only one - value for a property of a given name, so the property may only show - up once in PROPFIND responses. + values of a PCDATA element). A protected property is one which cannot be changed with a PROPPATCH request. There may be other requests which would result in a change to a protected property (as when a LOCK request affects the value of DAV:lockdiscovery). Note that a given property could be protected on one type of resource, but not protected on another type of resource. A computed property is one with a value defined in terms of a computation (based on the content and other properties of that resource, or even of some other resource). A computed property is always a protected property. COPY and MOVE behavior refers to local COPY and MOVE operations. For properties defined based on HTTP GET response headers (DAV:get*), the value could include LWS as defined in [RFC2616], section 4.2. Server implementors SHOULD NOT include extra LWS in these values, however client implementors MUST be prepared to handle extra LWS. -14.1. creationdate Property +15.1. creationdate Property Name: creationdate Purpose: Records the time and date the resource was created. Value: date-time (defined in [RFC3339], see the ABNF in section 5.6.) Protected: MAY be protected. Some servers allow DAV:creationdate to be changed to reflect the time the document was created if that is @@ -3919,21 +4078,21 @@ created with a COPY. It should not be set in a COPY. Description: The DAV:creationdate property SHOULD be defined on all DAV compliant resources. If present, it contains a timestamp of the moment when the resource was created. Servers that are incapable of persistently recording the creation date SHOULD instead leave it undefined (i.e. report "Not Found") -14.2. displayname Property +15.2. displayname Property Name: displayname Purpose: Provides a name for the resource that is suitable for presentation to a user. Value: Any text Protected: SHOULD NOT be protected. Note that servers implementing RFC2518 might have made this a protected property as this is a new @@ -3945,21 +4104,21 @@ Description: The DAV:displayname property should be defined on all DAV compliant resources. If present, the property contains a description of the resource that is suitable for presentation to a user. This property is defined on the resource, and hence SHOULD have the same value independent of the Request-URI used to retrieve it (thus computing this property based on the Request-URI is deprecated). -14.3. getcontentlanguage Property +15.3. getcontentlanguage Property Name: getcontentlanguage Purpose: Contains the Content-Language header value (from section 14.12 of [RFC2616]) as it would be returned by a GET without accept headers. Value: language-tag (language-tag is defined in section 3.10 of [RFC2616]). @@ -3969,93 +4128,92 @@ COPY/MOVE behaviour: This property value SHOULD be preserved in COPY and MOVE operations. Description: The DAV:getcontentlanguage property MUST be defined on any DAV compliant resource that returns the Content-Language header on a GET. -14.4. getcontentlength Property +15.4. getcontentlength Property Name: getcontentlength Purpose: Contains the Content-Length header returned by a GET without accept headers. Value: See section 14.13 of [RFC2616]. Protected: This property is computed, therefore protected. Description: The DAV:getcontentlength property MUST be defined on any DAV compliant resource that returns the Content-Length header in response to a GET. COPY/MOVE behaviour: This property value is dependent on the size of the destination resource, not the value of the property on the source resource. -14.5. getcontenttype Property +15.5. getcontenttype Property Name: getcontenttype Purpose: Contains the Content-Type header value (from section 14.17 of [RFC2616]) as it would be returned by a GET without accept headers. Value: media-type (defined in section 3.7 of [RFC2616]) - Protected: SHOULD NOT be protected, so clients may fix this value. - Note that servers implementing RFC2518 might have made this a - protected property as this is a new requirement. + Protected: Potentially protected if the server prefers to assign + content types on its own (see also discussion in Section 9.7.1). COPY/MOVE behaviour: This property value SHOULD be preserved in COPY and MOVE operations. Description: This property MUST be defined on any DAV compliant resource that returns the Content-Type header in response to a GET. -14.6. getetag Property +15.6. getetag Property Name: getetag Purpose: Contains the ETag header value (from section 14.19 of [RFC2616]) as it would be returned by a GET without accept headers. Value: entity-tag (defined in section 3.11 of [RFC2616]) Protected: MUST be protected because this value is created and controlled by the server. COPY/MOVE behaviour: This property value is dependent on the final state of the destination resource, not the value of the property on the source resource. Also note the considerations in - Section 8.1.6. + Section 8.7. Description: The getetag property MUST be defined on any DAV compliant resource that returns the Etag header. Refer to RFC2616 - for a complete definition of the semantics of an ETag. Note that - changes in properties or lock state MUST not cause a resource's - ETag to change. + for a complete definition of the semantics of an ETag, and to + Section 8.5 for a discussion of ETags in WebDAV. -14.7. getlastmodified Property +15.7. getlastmodified Property Name: getlastmodified + Purpose: Contains the Last-Modified header value (from section 14.29 of [RFC2616]) as it would be returned by a GET method without accept headers. Value: rfc1123-date (defined in section 3.3.1 of [RFC2616]) Protected: SHOULD be protected because some clients may rely on the value for appropriate caching behavior, or on the value of the Last-Modified header to which this property is linked. @@ -4061,56 +4219,57 @@ COPY/MOVE behaviour: This property value is dependent on the last modified date of the destination resource, not the value of the property on the source resource. Note that some server implementations use the file system date modified value for the DAV:getlastmodified value, and this can be preserved in a MOVE even when the HTTP Last-Modified value SHOULD change. Note that since [RFC2616] requires clients to use ETags where provided, a server implementing ETags can count on clients using a much better mechanism that modification dates for offline synchronization or - cache control. Also note the considerations in Section 8.1.6. + cache control. Also note the considerations in Section 8.7. Description: Note that the last-modified date on a resource SHOULD only reflect changes in the body (the GET responses) of the resource. A change in a property only SHOULD NOT cause the last- modified date to change, because clients MAY rely on the last- modified date to know when to overwrite the existing body. The DAV:getlastmodified property MUST be defined on any DAV compliant resource that returns the Last-Modified header in response to a GET. -14.8. lockdiscovery Property +15.8. lockdiscovery Property Name: lockdiscovery Purpose: Describes the active locks on a resource Protected: MUST be protected. Clients change the list of locks through LOCK and UNLOCK, not through PROPPATCH. COPY/MOVE behaviour: The value of this property depends on the lock state of the destination, not on the locks of the source resource. Recall that locks are not moved in a MOVE operation. Description: Returns a listing of who has a lock, what type of lock he has, the timeout type and the time remaining on the timeout, and the associated lock token. If there are no locks, but the server supports locks, the property will be present but contain zero 'activelock' elements. If there is one or more lock, an - 'activelock' element appears for each lock on the resource. + 'activelock' element appears for each lock on the resource. This + property is NOT lockable with respect to write locks (Section 7). -14.8.1. Example - Retrieving DAV:lockdiscovery +15.8.1. Example - Retrieving DAV:lockdiscovery >>Request PROPFIND /container/ HTTP/1.1 Host: www.example.com Content-Length: xxxx Content-Type: application/xml; charset="utf-8" @@ -4146,77 +4305,78 @@ HTTP/1.1 200 OK This resource has a single exclusive write lock on it, with an infinite timeout. -14.9. resourcetype Property +15.9. resourcetype Property Name: resourcetype Purpose: Specifies the nature of the resource. Protected: SHOULD be protected. Resource type is generally decided through the operation creating the resource (MKCOL vs PUT), not by PROPPATCH. COPY/MOVE behaviour: Generally a COPY/MOVE of a resource results in the same type of resource at the destination. Description: MUST be defined on all DAV compliant resources. Each child element identifies a specific type the resource belongs to, such as 'collection', which is the only resource type defined by - this specification (see Section 13.3). If the element contains + this specification (see Section 14.3). If the element contains the 'collection' child element plus additional unrecognized elements, it should generally be treated as a collection. If the element contains no recognized child elements, it should be treated as a non-collection resource. The default value is empty. This element MUST NOT contain text or mixed content. Any custom child element is considered to be an identifier for a resource type. Example: (fictional example to show extensibility) -14.10. supportedlock Property +15.10. supportedlock Property Name: supportedlock Purpose: To provide a listing of the lock capabilities supported by the resource. Protected: MUST be protected. Servers determine what lock mechanisms are supported, not clients. COPY/MOVE behaviour: This property value is dependent on the kind of locks supported at the destination, not on the value of the property at the source resource. Servers attempting to COPY to a destination should not attempt to set this property at the destination. Description: Returns a listing of the combinations of scope and access types which may be specified in a lock request on the resource. Note that the actual contents are themselves controlled by access controls so a server is not required to provide - information the client is not authorized to see. + information the client is not authorized to see. This property is + NOT lockable with respect to write locks (Section 7). -14.10.1. Example - Retrieving DAV:supportedlock +15.10.1. Example - Retrieving DAV:supportedlock >>Request PROPFIND /container/ HTTP/1.1 Host: www.example.com Content-Length: xxxx Content-Type: application/xml; charset="utf-8" @@ -4244,78 +4404,79 @@ HTTP/1.1 200 OK -15. Precondition/postcondition XML elements +16. Precondition/postcondition XML elements - As introduced in section Section 8.1.5, extra information on error + As introduced in section Section 8.6, extra information on error conditions can be included in the body of many status responses. This section makes requirements on the use of the error body mechanism and introduces a number of precondition and postcondition codes. A "precondition" of a method describes the state of the server that must be true for that method to be performed. A "postcondition" of a method describes the state of the server that must be true after that method has been completed. Each precondition and postcondition has a unique XML element associated with it. In a 207 Multi-Status response, the XML element - MUST appear inside a DAV:error element in the appropriate DAV: - responsedescription element. In all other error responses, the XML - element MUST be returned as the child of a top-level DAV:error - element in the response body, unless otherwise negotiated by the - request, along with an appropriate response status. The most common - response status codes are 403 (Forbidden) if the request should not - be repeated because it will always fail, and 409 (Conflict) if it is - expected that the user might be able to resolve the conflict and - resubmit the request. The DAV:error element MAY contain child - elements with specific error information and MAY be extended with any - custom child elements. + MUST appear inside an 'error' element in the appropriate 'propstat or + 'response' element depending on whether the condition applies to one + or more properties or the resource as a whole. In all other error + responses, the XML element MUST be returned as the child of a top- + level 'error' element in the response body, unless otherwise + negotiated by the request, along with an appropriate response status. + The most common response status codes are 403 (Forbidden) if the + request should not be repeated because it will always fail, and 409 + (Conflict) if it is expected that the user might be able to resolve + the conflict and resubmit the request. The 'error' element MAY + contain child elements with specific error information and MAY be + extended with any custom child elements. This mechanism does not take the place of using a correct numeric error code as defined here or in HTTP, because the client MUST always be able to take a reasonable course of action based only on the numeric error. However, it does remove the need to define new numeric error codes. The machine-readable codes used for this purpose are XML elements classified as preconditions and postconditions, so naturally any group defining a new error code can use their own namespace. As always, the "DAV:" namespace is reserved for use by IETF-chartered WebDAV working groups. - A server supporting "bis" SHOULD use the XML error whenever a - precondition or postcondition defined in this document is violated. - For error conditions not specified in this document, the server MAY - simply choose an appropriate numeric status and leave the response - body blank. However, a server MAY instead use a custom error code - and other supporting text, because even when clients do not - automatically recognize error codes they can be quite useful in + A server supporting this specification SHOULD use the XML error + whenever a precondition or postcondition defined in this document is + violated. For error conditions not specified in this document, the + server MAY simply choose an appropriate numeric status and leave the + response body blank. However, a server MAY instead use a custom + error code and other supporting text, because even when clients do + not automatically recognize error codes they can be quite useful in interoperability testing and debugging. Example - Response with precondition code" >>Response HTTP/1.1 423 Locked Content-Type: application/xml; charset="utf-8" Content-Length: xxxx - + /workspace/webdav/ - + In this example, a client unaware of a "Depth: infinity" lock on the parent collection "/workspace/webdav/" attempted to modify the collection member "/workspace/webdav/proposal.doc". Some other useful preconditions and postconditions have been defined in other specifications extending WebDAV, such as [RFC3744] (see particularly section 7.1.1), [RFC3253], and [RFC3648]. @@ -4342,21 +4503,21 @@ Purpose: The request could not succeed because a lock token should have been submitted. This element, if present, MUST contain at least one URL of a locked resource that prevented the request. In cases of MOVE, COPY and DELETE where collection locks are involved, it can be difficult for the client to find out which locked resource made the request fail -- but the server is only resonsible for returning one such locked resource. The server MAY return every locked resource that prevented the request from succeeding if it knows them all. - + Name: no-conflicting-lock (precondition) Use with: Typically 423 Locked Purpose: A LOCK request failed due the presence of an already existing conflicting lock. Note that a lock can be in conflict although the resource to which the request was directed is only indirectly locked. In this case, the precondition code can be used to inform the client about the resource which is the root of @@ -4388,155 +4549,162 @@ Name: propfind-finite-depth Use with: 403 Forbidden Purpose: (precondition) -- This server does not allow infinite-depth PROPFIND requests on collections. - Name: writable-property + Name: cannot-modify-protected-property Use with: 403 Forbidden Purpose: (precondition) -- The client attempted to set a read-only property in a PROPPATCH (such as DAV:getetag). - + -16. XML Extensibility in DAV +17. XML Extensibility in DAV The XML namespace extension [W3C.REC-xml-names-19990114] is used in this specification in order to allow for new XML elements to be added without fear of colliding with other element names. Although WebDAV request and response bodies can be extended by arbitrary XML elements, which can be ignored by the message recipient, an XML element in the "DAV:" namespace SHOULD NOT be used in the request or response body unless that XML element is explicitly defined in an IETF RFC reviewed by a WebDAV working group. - Extensibility with backwards-compatibility requires that both clients - and servers behave appropriately when unrecognized command extensions - are received. For XML processing, this means that clients and - servers MUST process received XML documents as if unrecognized - elements (and all children) and unrecognized attributes were not - there. Ignoring custom elements for backwards-compatibility can of - course be consistent with logging all information or presenting for - debugging. + For WebDAV to be both extensibile and backwards-compatible, both + clients and servers need to know how to behave when unexpected or + unrecognized command extensions are received. For XML processing, + this means that clients and servers MUST process received XML + documents as if unexpected elements and attributes (and all children + of unrecognized elements) were not there. An unexpected element or + attribute includes one which may be used in another context but is + not expected here. Ignoring such items for purposes of processing + can of course be consistent with logging all information or + presenting for debugging. 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. + property values where unexpected 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. + server where the server MUST record all 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. When XML is used for a request or response body, the Content-Type type SHOULD be application/xml. Implementations MUST accept both text/xml and application/xml in request and response bodies. Use of text/xml is deprecated. Processing instructions in XML SHOULD be ignored by recipients. Thus, specifications extending WebDAV SHOULD NOT use processing instructions to define normative behavior. XML DTD fragments are included for all the XML elements defined in this specification. However, correct XML will not be valid according to any DTD due to namespace usage and extension rules. In particular: - All elements defined in this specification use the "DAV:" + o All elements defined in this specification use the "DAV:" namespace, - Element ordering is irrelevant unless otherwise stated, - Extension attributes MAY be added, + o Element ordering is irrelevant unless otherwise stated, - For element type definitions of "ANY", the normative text + o Extension attributes MAY be added, + + o For element type definitions of "ANY", the normative text definition for that element defines what can be in it and what that means. - For element type definitions of "#PCDATA", extension elements MUST + o For element type definitions of "#PCDATA", extension elements MUST NOT be added. - For other element type definitions, including "EMPTY", extension + o For other element type definitions, including "EMPTY", extension elements MAY be added. Note that this means that elements containing elements cannot be extended to contain text, and vice versa. With DTD validation relaxed by the rules above, the constraints described by the DTD fragments are normative (see for example Appendix A A recipient of a WebDAV message with an XML body MUST NOT validate the XML document according to any hard-coded or dynamically- declared DTD. Note that this section describes backwards-compatible extensibility rules. There might also be times when an extension is designed not to be backwards-compatible, for example defining an extension that reuses an XML element defined in this document but omitting one of the child elements required by the DTDs in this specification. -17. DAV Compliance Classes +18. DAV Compliance Classes A DAV compliant resource can advertise several classes of compliance. A client can discover the compliance classes of a resource by executing OPTIONS on the resource, and examining the "DAV" header which is returned. Note particularly that resources are spoken of as being compliant, rather than servers. That is because theoretically some resources on a server could support different feature sets. E.g. a server could have a sub-repository where an advanced feature like server was supported, even if that feature was not supported on all servers. Since this document describes extensions to the HTTP/1.1 protocol, minimally all DAV compliant resources, clients, and proxies MUST be compliant with [RFC2616]. A resource that is class 2 compliant must also be class 1 compliant, - and a resource that is compliant with "bis" must also be class 1 + and a resource that is class 3 compliant must also be class 1 compliant. -17.1. Class 1 +18.1. Class 1 A class 1 compliant resource MUST meet all "MUST" requirements in all sections of this document. Class 1 compliant resources MUST return, at minimum, the value "1" in the DAV header on all responses to the OPTIONS method. -17.2. Class 2 +18.2. Class 2 A class 2 compliant resource MUST meet all class 1 requirements and support the LOCK method, the DAV:supportedlock property, the DAV: lockdiscovery property, the Time-Out response header and the Lock- Token request header. A class "2" compliant resource SHOULD also support the Time-Out request header and the 'owner' XML element. Class 2 compliant resources MUST return, at minimum, the values "1" and "2" in the DAV header on all responses to the OPTIONS method. -17.3. Class 'bis' +18.3. Class 3 A resource can explicitly advertise its support for the revisions to - RFC2518 made in this document. Class 1 must be supported as well. - Class 2 MAY be supported. + RFC2518 made in this document. Class 1 MUST be supported as well. + Class 2 MAY be supported. Advertising class 3 support in addition to + class 1 and 2 means that the server supports all the requirements in + this specification. Advertising class 3 and class 1 support, but not + class 2, means that the server supports all the requirements in this + specification except possibly those that involve locking support. Example: - DAV: 1, bis + DAV: 1, 3 -18. Internationalization Considerations +19. Internationalization Considerations In the realm of internationalization, this specification complies with the IETF Character Set Policy [RFC2277]. In this specification, human-readable fields can be found either in the value of a property, or in an error message returned in a response entity body. In both cases, the human-readable content is encoded using XML, which has explicit provisions for character set tagging and encoding, and requires that XML processors read XML elements encoded, at minimum, using the UTF-8 [RFC3629] and UTF-16 encodings of the ISO 10646 multilingual plane. XML examples in this specification demonstrate @@ -4583,33 +4751,33 @@ codes, including with each status code a short, English description of the code (e.g., 423 (Locked)). While the possibility exists that a poorly crafted user agent would display this message to a user, internationalized applications will ignore this message, and display an appropriate message in the user's language and character set. Since interoperation of clients and servers does not require locale information, this specification does not specify any mechanism for transmission of this information. -19. Security Considerations +20. Security Considerations This section is provided to detail issues concerning security implications of which WebDAV applications need to be aware. All of the security considerations of HTTP/1.1 (discussed in [RFC2616]) and XML (discussed in [RFC3023]) also apply to WebDAV. In addition, the security risks inherent in remote authoring require stronger authentication technology, introduce several new privacy concerns, and may increase the hazards from poor server design. These issues are detailed below. -19.1. Authentication of Clients +20.1. Authentication of Clients Due to their emphasis on authoring, WebDAV servers need to use authentication technology to protect not just access to a network resource, but the integrity of the resource as well. Furthermore, the introduction of locking functionality requires support for authentication. A password sent in the clear over an insecure channel is an inadequate means for protecting the accessibility and integrity of a resource as the password may be intercepted. Since Basic @@ -4624,21 +4792,21 @@ connection over a network which is physically secure, for example, an isolated network in a building with restricted access. WebDAV applications MUST support the Digest authentication scheme [RFC2617]. Since Digest authentication verifies that both parties to a communication know a shared secret, a password, without having to send that secret in the clear, Digest authentication avoids the security problems inherent in Basic authentication while providing a level of authentication which is useful in a wide range of scenarios. -19.2. Denial of Service +20.2. Denial of Service Denial of service attacks are of special concern to WebDAV servers. WebDAV plus HTTP enables denial of service attacks on every part of a system's resources. o The underlying storage can be attacked by PUTting extremely large files. o Asking for recursive operations on large collections can attack processing time. @@ -4648,58 +4816,58 @@ WebDAV servers need to be aware of the possibility of a denial of service attack at all levels. The proper response to such an attack MAY be to simply drop the connection, or if the server is able to make a response, the server MAY use a 400-level status request such as 400 (Bad Request) and indicate why the request was refused (a 500- level status response would indicate that the problem is with the server, whereas unintentional DOS attacks are something the client is capable of remedying). -19.3. Security through Obscurity +20.3. Security through Obscurity WebDAV provides, through the PROPFIND method, a mechanism for listing the member resources of a collection. This greatly diminishes the effectiveness of security or privacy techniques that rely only on the difficulty of discovering the names of network resources. Users of WebDAV servers are encouraged to use access control techniques to prevent unwanted access to resources, rather than depending on the relative obscurity of their resource names. -19.4. Privacy Issues Connected to Locks +20.4. Privacy Issues Connected to Locks When submitting a lock request a user agent may also submit an 'owner' XML field giving contact information for the person taking out the lock (for those cases where a person, rather than a robot, is taking out the lock). This contact information is stored in a DAV: lockdiscovery property on the resource, and can be used by other collaborators to begin negotiation over access to the resource. However, in many cases this contact information can be very private, and should not be widely disseminated. Servers SHOULD limit read access to the DAV:lockdiscovery property as appropriate. Furthermore, user agents SHOULD provide control over whether contact information is sent at all, and if contact information is sent, control over exactly what information is sent. -19.5. Privacy Issues Connected to Properties +20.5. Privacy Issues Connected to Properties Since property values are typically used to hold information such as the author of a document, there is the possibility that privacy concerns could arise stemming from widespread access to a resource's property data. To reduce the risk of inadvertent release of private information via properties, servers are encouraged to develop access control mechanisms that separate read access to the resource body and read access to the resource's properties. This allows a user to control the dissemination of their property data without overly restricting access to the resource's contents. -19.6. Implications of XML Entities +20.6. Implications of XML Entities XML supports a facility known as "external entities", defined in section 4.2.2 of [XML], which instruct an XML processor to retrieve and include additional XML. An external XML entity can be used to append or modify the document type declaration (DTD) associated with an XML document. An external XML entity can also be used to include XML within the content of an XML document. For non-validating XML, such as the XML used in this specification, including an external XML entity is not required by XML. However, XML does state that an XML processor may, at its discretion, include the external XML entity. @@ -4724,25 +4892,25 @@ containing the external XML entity. Furthermore, there's also a risk based on the evaluation of "internal entities" as defined in section 4.2.2 of [XML]. A small, carefully crafted request using nested internal entities may require enormous amounts of memory and/or processing time to process. Server implementors should be aware of this risk and configure their XML parsers so that requests like these can be detected and rejected as early as possible. -19.7. Risks Connected with Lock Tokens +20.7. Risks Connected with Lock Tokens This specification encourages the use of "A Universally Unique Identifier (UUID) URN Namespace" ([RFC4122]) for lock tokens - Section 6.4, in order to guarantee their uniqueness across space and + Section 6.5, in order to guarantee their uniqueness across space and time. Version 1 UUIDs (defined in section 4) MAY contain a "node" field that "consists of an IEEE 802 MAC address, usually the host address. For systems with multiple IEEE addresses, any available one can be used". Since a WebDAV server will issue many locks over its lifetime, the implication is that it may also be publicly exposing its IEEE 802 address. There are several risks associated with exposure of IEEE 802 addresses. Using the IEEE 802 address: @@ -4753,162 +4921,151 @@ running a WebDAV server. o It may be possible to determine the number of each type of computer running WebDAV. This risk only applies to host address based UUID versions. Section 4 of [RFC4122] describes several other mechanisms for generating UUIDs that do involve the host address and therefore do not suffer from this risk. -19.8. Hosting malicious scripts executed on client machines - - HTTP has the ability to host scripts which are executed on client - machines. These scripts can be used to read another user's cookies - and therefore may provide an attacker the ability to use another - user's session, assume their identity temporarily and gain access to - their resources. Other attacks are also possible with client- - executed scripts. - - WebDAV may worsen this situation only by making it easier for a Web - server to host content provided by many different authors (making it - harder to trust the content providers) and to host content with - restricted access alongside public pages (see particularly RFC3744). - Note also that allowing clients to set the Content-Type might make it - possible for malevolent clients to bypass type checks in other user - agents. - - HTTP servers may mitigate some of these threats by filtering content - in areas where many authors contribute pages -- the server could, for - example, remove script from HTML pages. - - This vulnerability should provide yet another reason for server - implementors and administrators not to replace authentication - mechanisms with cookie-based session tokens if there's any sensitive - information relying on the authenticated identity. +20.8. Hosting Malicious Content - HTTP and WebDAV client implementors might consider locking down the - use of scripts and cookies based on these considerations. + HTTP has the ability to host programs which are executed on client + machines. These programs can take many forms including web scripts, + executables, plug in modules, and macros in documents. WebDAV does + not change any of the security concerns around these programs yet + often WebDAV is used in contexts where a wide range of users can + publish documents on a server. The server might not have a close + trust relationship with the author that is publishing the document. + Servers that allow clients to publish arbitrary content can usefully + implement precautions to check that content published to the server + is not harmful to other clients. Servers could do this by techniques + such as restricting the types of content that is allowed to be + published and running virus and malware detection software on + published content. Servers can also mitigate the risk by having + appropriate access restriction and authentication of users that are + allowed to publish content to the server. -20. IANA Considerations +21. IANA Considerations -20.1. New URI Schemes +21.1. New URI Schemes This specification defines two URI schemes: 1. the "opaquelocktoken" scheme defined in Appendix C, and 2. the "DAV" URI scheme, which historically was used in RFC2518 to disambiguate WebDAV property and XML element names and which continues to be used for that purpose in this specification and others extending WebDAV. Creation of identifiers in the "DAV:" namespace is controlled by the IETF. Note that defining new URI schemes for XML namespaces is now discouraged. "DAV:" was defined before standard best practices emerged. -20.2. XML Namespaces +21.2. XML Namespaces XML namespaces disambiguate WebDAV property names and XML elements. Any WebDAV user or application can define a new namespace in order to create custom properties or extend WebDAV XML syntax. IANA does not need to manage such namespaces, property names or element names. -20.3. Message Header Fields +21.3. Message Header Fields The message header fields below should be added to the permanent registry (see [RFC3864]). -20.3.1. DAV +21.3.1. DAV Header field name: DAV Applicable protocol: http Status: standard Author/Change controller: IETF - Specification document: this specification (Section 9.1) + Specification document: this specification (Section 10.1) -20.3.2. Depth +21.3.2. Depth Header field name: Depth Applicable protocol: http Status: standard Author/Change controller: IETF - Specification document: this specification (Section 9.2) + Specification document: this specification (Section 10.2) -20.3.3. Destination +21.3.3. Destination Header field name: Destination Applicable protocol: http Status: standard Author/Change controller: IETF - Specification document: this specification (Section 9.3) + Specification document: this specification (Section 10.3) -20.3.4. If +21.3.4. If Header field name: If Applicable protocol: http Status: standard Author/Change controller: IETF - Specification document: this specification (Section 9.4) + Specification document: this specification (Section 10.4) -20.3.5. Lock-Token +21.3.5. Lock-Token Header field name: Lock-Token Applicable protocol: http Status: standard Author/Change controller: IETF - Specification document: this specification (Section 9.5) + Specification document: this specification (Section 10.5) -20.3.6. Overwrite +21.3.6. Overwrite Header field name: Overwrite Applicable protocol: http Status: standard Author/Change controller: IETF - Specification document: this specification (Section 9.6) + Specification document: this specification (Section 10.6) -20.3.7. Timeout +21.3.7. Timeout Header field name: Timeout Applicable protocol: http Status: standard Author/Change controller: IETF - Specification document: this specification (Section 9.7) + Specification document: this specification (Section 10.7) -21. Acknowledgements +22. Acknowledgements A specification such as this thrives on piercing critical review and withers from apathetic neglect. The authors gratefully acknowledge the contributions of the following people, whose insights were so valuable at every stage of our work. Contributors to RFC2518 Terry Allen, Harald Alvestrand, Jim Amsden, Becky Anderson, Alan Babich, Sanford Barr, Dylan Barrell, Bernard Chester, Tim Berners- @@ -4941,47 +5098,47 @@ due to IETF author count restrictions they can take credit for the majority of the design of WebDAV. Additional Contributors to This Specification Valuable contributions to this specification came from some already named. New and significant contributors to this specification must also be gratefully acknowledged. Julian Reschke, Geoff Clemm, Joel Soderberg, and Dan Brotsky hashed out specific text on the list or in meetings. Joe Hildebrand and Cullen Jennings helped close many - issues. Barry Lind described an additional security consideration. - - Jason Crawford tracked issue status for this document for a period of + issues. Barry Lind described an additional security consideration + and Cullen Jennings provided text for that consideration. Jason + Crawford tracked issue status for this document for a period of years, followed by Elias Sinderson. Elias and Jim Whitehead collaborated on specific document text. -21.1. Previous Authors' Addresses +22.1. Previous Authors' Addresses Y. Y. Goland, Microsoft Corporation, One Microsoft Way, Redmond, WA 98052-6399. Email: yarong@microsoft.com. E. J. Whitehead, Jr., Dept. Of Information and Computer Science, University of California, Irvine, Irvine, CA 92697-3425. Email: ejw@ics.uci.edu. A. Faizi, Netscape, 685 East Middlefield Road, Mountain View, CA 94043. Email: asad@netscape.com. S. R. Carter, Novell, 1555 N. Technology Way, M/S ORM F111, Orem, UT 84097-2399. Email: srcarter@novell.com. D. Jensen, Novell, 1555 N. Technology Way, M/S ORM F111, Orem, UT 84097-2399. Email: dcjensen@novell.com. -22. References +23. References -22.1. Normative References +23.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2277] Alvestrand, H., "IETF Policy on Character Sets and Languages", BCP 18, RFC 2277, January 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. @@ -5012,21 +5169,21 @@ [W3C.REC-xml-names-19990114] Hollander, D., Bray, T., and A. Layman, "Namespaces in XML", W3C REC REC-xml-names-19990114, January 1999. [XML] Bray, T., Paoli, J., Sperberg-McQueen, C., Maler, E., and F. Yergeau, "Extensible Markup Language (XML) 1.0 (Third Edition)", W3C REC-xml-20040204, February 2004, . -22.2. Informational References +23.2. Informational References [RFC2291] Slein, J., Vitali, F., Whitehead, E., and D. Durand, "Requirements for a Distributed Authoring and Versioning Protocol for the World Wide Web", RFC 2291, February 1998. [RFC2518] Goland, Y., Whitehead, E., Faizi, A., Carter, S., and D. Jensen, "HTTP Extensions for Distributed Authoring -- WEBDAV", RFC 2518, February 1999. [RFC3023] Murata, M., St. Laurent, S., and D. Kohn, "XML Media @@ -5091,21 +5248,21 @@ client running over a bandwidth limited line who intended to execute a propname would be in for a big surprise if the server treated the command as an allprop. Additionally, if a server were lenient and decided to reply to this request, the results would vary randomly from server to server, with some servers executing the allprop directive, and others executing the propname directive. This reduces interoperability rather than increasing it. -A.4. Example - Unknown XML Element +A.4. Example - Unexpected XML Element The previous example was illegal because it contained two elements that were explicitly banned from appearing together in the propfind element. However, XML is an extensible language, so one can imagine new elements being defined for use with propfind. Below is the request body of a PROPFIND and, like the previous example, must be rejected with a 400 (Bad Request) by a server that does not understand the expired-props element. @@ -5117,22 +5274,23 @@ To understand why a 400 (Bad Request) is returned let us look at the request body as the server unfamiliar with expired-props sees it. As the server does not understand the 'expired-props' element, according to the WebDAV-specific XML processing rules specified in - Section 16, it must ignore it. Thus the server sees an empty - propfind, which by the definition of the propfind element is illegal. + Section 17, it must process the request as if the element were not + there. Thus the server sees an empty propfind, which by the + definition of the propfind element is illegal. Please note that had the extension been additive it would not necessarily have resulted in a 400 (Bad Request). For example, imagine the following request body for a PROPFIND: *boss* @@ -5222,21 +5380,21 @@ The first approach is to perform a request that ought to require authentication. However, it's possible that a server might handle any request even without authentication, so to be entirely safe the client could add a conditional header to ensure that even if the request passes permissions checks it's not actually handled by the server. An example of following this approach would be to use a PUT request with an "If-Match" header with a made-up ETag value. This approach might fail to result in an authentication challenge if the server does not test authorization before testing conditionals as is - required (see Section 8.1.3), or if the server does not need to test + required (see Section 8.4), or if the server does not need to test authorization. Example - forcing auth challenge with write request >>Request PUT /forceauth.txt HTTP/1.1 Host: www.example.com If-Match: "xxx" Content-Type: text/plain @@ -5253,162 +5411,163 @@ username, invalid password, or if it doesn't even handle Basic authentication. This seems likely to work because of the requirements of RFC2617: "If the origin server does not wish to accept the credentials sent with a request, it SHOULD return a 401 (Unauthorized) response. The response MUST include a WWW-Authenticate header field containing at least one (possibly new) challenge applicable to the requested resource." + There's a slight problem with implementing that recommendation in + some cases, because some servers do not even have challenge + information for certain resources. Thus, when there's no way to + authenticate to a resource or the resource is entirely publicly + available over all accepted methods, the server MAY ignore the + Authorization header, and the client presumably try again later. + Example - forcing auth challenge with Authorization header >>Request PROPFIND /docs/ HTTP/1.1 Host: www.example.com Authorization: Basic QWxhZGRpbjpvcGVuIHNlc2FtZQ== Content-type: application/xml; charset="utf-8" Content-Length: xxxx [body omitted] Appendix E. Summary of changes from RFC2518 - This section describes changes that are likely to result in + This section lists changes that are likely to result in implementation changes due to tightened requirements or changed behavior. -E.1. Changes Notable to Server Implementors +E.1. Changes for both Clients and Servers - Tightened requirements for storing property values (Section 4.3) when - "xml:lang" appears and also when values are XML fragments - (specifically on preserving prefixes, namespaces and whitespace.) + New value for "DAV:" header (Section 10.1) to advertise support for + this specification. + + Replaced lock-null resources with simpler locked empty resources + (Section 7.3). + + Support for UTF-16 now required (ref (Section 19)). Changed meaning of PROPFIND 'allprop' so that it doesn't have to return live properties not defined in this specification; added 'include' syntax so that clients can retrieve specific live properties along with 'allprop' results. - Tightened requirements on which properties are protected and computed - (Section 14). + Changes in LOCK refresh (not implicit anymore, uses LOCK without body + with Lock-Token request header) - Several tightened requirements for general response handling - (Section 8.1), including ETag and Location header, and reminder to - use Date header. + New element 'location' defined for handling redirected resources in + Multi-Status. Defined response bodies for error responses, including several - machine-readable precondition or postcondition codes (Section 15) for + machine-readable precondition or postcondition codes (Section 16) for error detail. - Tightened requirements for URL construction in PROPFIND (Section 8.2) - responses. + Removed definition of "source" property and special handling for + dynamic resources. - Tightened requirements for checking identity of lock creators - (Section 6.3) during operations affected by locks. + The definition of the 102 Processing response was removed and servers + ought to stop sending that response when they implement this + specification; clients may be able to remove code that handles this. - Tightened requirements for copying properties (Section 8.9.2) and - moving properties (Section 8.10.1). +E.2. Changes Notable to Server Implementors - Tightened requirements on preserving 'owner' field in locks - (Section 8.11). Added "lockroot" element to lockdiscovery - information. + Tightened requirements for storing property values (Section 4.3) when + "xml:lang" appears and also when values are XML fragments + (specifically on preserving prefixes, namespaces and whitespace.) - New value for "DAV:" header (Section 9.1) to advertise support for - this specification. + Tightened requirements on which properties are protected and computed + (Section 15). - Some changes for "If:" header (Section 9.4), including "DAV:no-lock" - state token and requirement to evaluate entire header. + Several tightened requirements for general response handling + (Section 8), including ETag and Location header, and reminder to use + Date header. - Support for UTF-16 now required (ref (Section 18)). + Requirements for URL construction in Multi-Status responses, + Destination and If headers: more consistent and mostly tighter + requirements. - Removed definition of "source" property and special handling for - dynamic resources + Tightened requirements for checking identity of lock creators + (Section 6.4) during operations affected by locks. - Replaced lock-null resources with simpler locked empty resources - (Section 7.5). Lock-null resources are now not compliant with the - requirements in this specification. + Tightened requirements for copying properties (Section 9.8.2) and + moving properties (Section 9.9.1). - Encouraged servers to change ETags (Section 8.1.4) only when body of - resource changes. + Tightened requirements on preserving 'owner' field in locks + (Section 9.10). Added "lockroot" element to lockdiscovery + information. - The definition of the 102 Processing response was removed and servers - ought to stop sending that response when they implement this - specification. + Some changes for "If:" header (Section 10.4) handling, including + "DAV:no-lock" state token. + + Encouraged servers to change ETags (Section 8.5) only when body of + resource changes. Previously, servers were encouraged to return 409 status code in response to a collection LOCK request if some resource could not be locked. Now servers should use 207 Multi-Status instead. - New element 'location' defined for handling redirected resources in - Multi-Status. - Only 'rfc1123-date' productions are legal as values for DAV: getlastmodified. New explicit requirement to do authorization checks before - conditional checks (Section 8.1.3). + conditional checks (Section 8.4). Defined idempotence, safeness and cacheability for all new methods. Depth: Infinity doesn't affect other headers; by default these - headers only apply to the Request-URI (Section 9.4). + headers only apply to the Request-URI (Section 10.4). -E.2. Changes Notable to Client Implementors +E.3. Changes Notable to Client Implementors Tightened requirements for supporting WebDAV collections (Section 5.2) within resources that do not support WebDAV (e.g. servlet containers). - Redefined 'allprop' PROPFIND requests so that the server does not - have to return all properties. - Servers are no longer required to support all depth "infinity" PROPFIND requests, so clients need to be able to handle that and do multiple depth "1" requests instead. No more "propertybehavior" specification allowed in MOVE and COPY requests + The change in behavior of LOCK with an unmapped URL might affect client implementations that counted on lock-null resources disappearing when the lock expired. Clients can no longer rely on that cleanup happening. - Support for UTF-16 now required (ref (Section 18)). - - Removed definition of "source" property and special handling for - dynamic resources. - - The definition of the 102 Processing response was removed and clients - can safely remove code (if any) that deals with this. - - Servers may now reject PROPFIND depth "infinity" requests. - Clients use Lock-Token header, not the If header, to provide lock - token when renewing lock. Section 8.11.1 + token when renewing lock. Section 9.10.2 Clients must refresh locks explicitly as this is now the only way to renew timeout. Appendix F. Change Log (to be removed by RFC Editor before publication) F.1. Changes from -05 to -06 Specified that a successful LOCK request to an unmapped URL creates a new, empty locked resource. Resolved UNLOCK_NEEDS_IF_HEADER by clarifying that only Lock-Token header is needed on UNLOCK. - Added Section 15 on preconditions and postconditions and defined a - number of preconditions and postconditions. The 'lock-token-present' - precondition resolves the REPORT_OTHER_RESOURCE_LOCKED issue. + Added Section 16 on preconditions and postconditions and defined a + number of preconditions and postconditions. The 'lock-token- + submitted' precondition resolves the REPORT_OTHER_RESOURCE_LOCKED + issue. Added example of matching lock token to URI in the case of a collection lock in the If header section. Removed ability for Destination header to take "abs_path" in order to keep consistent with other places where client provides URLs (If header, href element in request body) Clarified the href element - that it generally contains HTTP URIs but not always. @@ -5559,23 +5719,43 @@ not recommend use of 414 for over-long Destination URI, bug 179 Changes for bug 10, 31, 42, 44, 46, 47, 80, 86, 99, 124, 132, 143, 147, 152, 166, 177, 188, 216, 218 Various changes discussed in conference call, including bug 10, 42, 44, 80, 97, 152. Bugs 55, 85, 86 +F.7. Changes in -11 + + Incorporated GULP (Lock model) into document, making a fair number of + changes to rationalize the new order of explaining things, keeping + text that explains a lock model concept in more detail but removing + text that is redundant or inconsistent. + + Various bugs including 46, 48, 53, 97, 152, 179, 184, 188, 200, 210, + 211, and 225. Moved URL Handling from Multi-Status section to + general request and response handling section as it now applies to + Destination and If as well as 'href' in Multi-Status. Moved GR&RH + section up one level to be the new Section 8. + + Bug 53, 184, 210, 213, 217, 221 + Further rewriting of URL Handling section. Changes resulting from + discussion of empty locked resources and how servers should handle + Content-Type in that situation. Bug 48, 179. + + Bug 227, 228, + Author's Address - Lisa Dusseault + Lisa Dusseault (editor) Open Source Application Foundation 2064 Edgewood Dr. Palo Alto, CA 94303 US Email: lisa@osafoundation.org Intellectual Property Statement The IETF takes no position regarding the validity or scope of any