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(See the Legal Provisions document at https://trustee.ietf.org/license-info for more information.) -- The document date (September 11, 2009) is 5339 days in the past. Is this intentional? Checking references for intended status: Experimental ---------------------------------------------------------------------------- ** Obsolete normative reference: RFC 2616 (Obsoleted by RFC 7230, RFC 7231, RFC 7232, RFC 7233, RFC 7234, RFC 7235) Summary: 2 errors (**), 0 flaws (~~), 4 warnings (==), 2 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group G. Clemm 3 Internet-Draft IBM 4 Intended status: Experimental J. Crawford 5 Expires: March 15, 2010 IBM Research 6 J. Reschke, Ed. 7 greenbytes 8 J. Whitehead 9 U.C. Santa Cruz 10 September 11, 2009 12 Binding Extensions to Web Distributed Authoring and Versioning (WebDAV) 13 draft-ietf-webdav-bind-26 15 Status of this Memo 17 This Internet-Draft is submitted to IETF in full conformance with the 18 provisions of BCP 78 and BCP 79. This document may contain material 19 from IETF Documents or IETF Contributions published or made publicly 20 available before November 10, 2008. The person(s) controlling the 21 copyright in some of this material may not have granted the IETF 22 Trust the right to allow modifications of such material outside the 23 IETF Standards Process. Without obtaining an adequate license from 24 the person(s) controlling the copyright in such materials, this 25 document may not be modified outside the IETF Standards Process, and 26 derivative works of it may not be created outside the IETF Standards 27 Process, except to format it for publication as an RFC or to 28 translate it into languages other than English. 30 Internet-Drafts are working documents of the Internet Engineering 31 Task Force (IETF), its areas, and its working groups. Note that 32 other groups may also distribute working documents as Internet- 33 Drafts. 35 Internet-Drafts are draft documents valid for a maximum of six months 36 and may be updated, replaced, or obsoleted by other documents at any 37 time. It is inappropriate to use Internet-Drafts as reference 38 material or to cite them other than as "work in progress." 40 The list of current Internet-Drafts can be accessed at 41 http://www.ietf.org/ietf/1id-abstracts.txt. 43 The list of Internet-Draft Shadow Directories can be accessed at 44 http://www.ietf.org/shadow.html. 46 This Internet-Draft will expire on March 15, 2010. 48 Copyright Notice 49 Copyright (c) 2009 IETF Trust and the persons identified as the 50 document authors. All rights reserved. 52 This document is subject to BCP 78 and the IETF Trust's Legal 53 Provisions Relating to IETF Documents in effect on the date of 54 publication of this document (http://trustee.ietf.org/license-info). 55 Please review these documents carefully, as they describe your rights 56 and restrictions with respect to this document. 58 Abstract 60 This specification defines bindings, and the BIND method for creating 61 multiple bindings to the same resource. Creating a new binding to a 62 resource causes at least one new URI to be mapped to that resource. 63 Servers are required to ensure the integrity of any bindings that 64 they allow to be created. 66 Editorial Note (To be removed by RFC Editor before publication) 68 Please send comments to the Distributed Authoring and Versioning 69 (WebDAV) working group at , which may be 70 joined by sending a message with subject "subscribe" to 71 . Discussions of the WEBDAV 72 working group are archived at 73 . 75 lists 76 all registered issues since draft 02. 78 Table of Contents 80 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 5 81 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 6 82 1.2. Method Preconditions and Postconditions . . . . . . . . . 8 83 2. Overview of Bindings . . . . . . . . . . . . . . . . . . . . . 8 84 2.1. Bindings to Collections . . . . . . . . . . . . . . . . . 8 85 2.1.1. Bind Loops . . . . . . . . . . . . . . . . . . . . . . 9 86 2.2. URI Mappings Created by a new Binding . . . . . . . . . . 9 87 2.3. COPY and Bindings . . . . . . . . . . . . . . . . . . . . 10 88 2.3.1. Example: COPY with 'Depth: infinity' in Presence 89 of Bind Loops . . . . . . . . . . . . . . . . . . . . 12 90 2.3.2. Example: COPY updating multiple Bindings . . . . . . . 14 91 2.3.3. Example: COPY with 'Depth: infinity' with Multiple 92 Bindings to a Leaf Resource . . . . . . . . . . . . . 15 93 2.4. DELETE and Bindings . . . . . . . . . . . . . . . . . . . 16 94 2.5. MOVE and Bindings . . . . . . . . . . . . . . . . . . . . 16 95 2.5.1. Example: Simple MOVE . . . . . . . . . . . . . . . . . 17 96 2.5.2. Example: MOVE Request causing a Bind Loop . . . . . . 17 97 2.6. PROPFIND and Bindings . . . . . . . . . . . . . . . . . . 19 98 2.7. Determining Whether Two Bindings Are to the Same 99 Resource . . . . . . . . . . . . . . . . . . . . . . . . . 19 100 2.8. Discovering the Bindings to a Resource . . . . . . . . . . 20 101 3. Properties . . . . . . . . . . . . . . . . . . . . . . . . . . 20 102 3.1. DAV:resource-id Property . . . . . . . . . . . . . . . . . 20 103 3.2. DAV:parent-set Property . . . . . . . . . . . . . . . . . 21 104 3.2.1. Example for DAV:parent-set Property . . . . . . . . . 21 105 4. BIND Method . . . . . . . . . . . . . . . . . . . . . . . . . 22 106 4.1. Example: BIND . . . . . . . . . . . . . . . . . . . . . . 25 107 5. UNBIND Method . . . . . . . . . . . . . . . . . . . . . . . . 25 108 5.1. Example: UNBIND . . . . . . . . . . . . . . . . . . . . . 27 109 6. REBIND Method . . . . . . . . . . . . . . . . . . . . . . . . 27 110 6.1. Example: REBIND . . . . . . . . . . . . . . . . . . . . . 29 111 6.2. Example: REBIND in Presence of Locks and Bind Loops . . . 30 112 7. Additional Status Codes . . . . . . . . . . . . . . . . . . . 32 113 7.1. 208 Already Reported . . . . . . . . . . . . . . . . . . . 32 114 7.1.1. Example: PROPFIND by Bind-Aware Client . . . . . . . . 33 115 7.1.2. Example: PROPFIND by Non-Bind-Aware Client . . . . . . 35 116 7.2. 506 Loop Detected . . . . . . . . . . . . . . . . . . . . 35 117 8. Capability Discovery . . . . . . . . . . . . . . . . . . . . . 35 118 8.1. OPTIONS Method . . . . . . . . . . . . . . . . . . . . . . 35 119 8.2. 'DAV' Request Header . . . . . . . . . . . . . . . . . . . 35 120 9. Relationship to WebDAV Access Control Protocol . . . . . . . . 36 121 10. Relationship to Versioning Extensions to WebDAV . . . . . . . 36 122 11. Security Considerations . . . . . . . . . . . . . . . . . . . 38 123 11.1. Privacy Concerns . . . . . . . . . . . . . . . . . . . . . 39 124 11.2. Bind Loops . . . . . . . . . . . . . . . . . . . . . . . . 39 125 11.3. Bindings, and Denial of Service . . . . . . . . . . . . . 39 126 11.4. Private Locations May Be Revealed . . . . . . . . . . . . 39 127 11.5. DAV:parent-set and Denial of Service . . . . . . . . . . . 39 128 12. Internationalization Considerations . . . . . . . . . . . . . 39 129 13. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 40 130 14. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 40 131 15. References . . . . . . . . . . . . . . . . . . . . . . . . . . 40 132 15.1. Normative References . . . . . . . . . . . . . . . . . . . 40 133 15.2. Informative References . . . . . . . . . . . . . . . . . . 41 134 Appendix A. Clarification to RFC4918 Usage of the Term 'Lock 135 Root' . . . . . . . . . . . . . . . . . . . . . . . . 41 136 A.1. Example: Locking and Multiple Bindings . . . . . . . . . . 42 137 Appendix B. Change Log (to be removed by RFC Editor before 138 publication) . . . . . . . . . . . . . . . . . . . . 43 139 B.1. Since draft-ietf-webdav-bind-02 . . . . . . . . . . . . . 43 140 B.2. Since draft-ietf-webdav-bind-03 . . . . . . . . . . . . . 43 141 B.3. Since draft-ietf-webdav-bind-04 . . . . . . . . . . . . . 43 142 B.4. Since draft-ietf-webdav-bind-05 . . . . . . . . . . . . . 43 143 B.5. Since draft-ietf-webdav-bind-06 . . . . . . . . . . . . . 44 144 B.6. Since draft-ietf-webdav-bind-07 . . . . . . . . . . . . . 44 145 B.7. Since draft-ietf-webdav-bind-08 . . . . . . . . . . . . . 44 146 B.8. Since draft-ietf-webdav-bind-09 . . . . . . . . . . . . . 44 147 B.9. Since draft-ietf-webdav-bind-10 . . . . . . . . . . . . . 44 148 B.10. Since draft-ietf-webdav-bind-11 . . . . . . . . . . . . . 44 149 B.11. Since draft-ietf-webdav-bind-12 . . . . . . . . . . . . . 45 150 B.12. Since draft-ietf-webdav-bind-13 . . . . . . . . . . . . . 45 151 B.13. Since draft-ietf-webdav-bind-14 . . . . . . . . . . . . . 45 152 B.14. Since draft-ietf-webdav-bind-15 . . . . . . . . . . . . . 45 153 B.15. Since draft-ietf-webdav-bind-16 . . . . . . . . . . . . . 46 154 B.16. Since draft-ietf-webdav-bind-17 . . . . . . . . . . . . . 46 155 B.17. Since draft-ietf-webdav-bind-18 . . . . . . . . . . . . . 46 156 B.18. Since draft-ietf-webdav-bind-19 . . . . . . . . . . . . . 46 157 B.19. Since draft-ietf-webdav-bind-20 . . . . . . . . . . . . . 46 158 B.20. Since draft-ietf-webdav-bind-21 . . . . . . . . . . . . . 46 159 B.21. Since draft-ietf-webdav-bind-22 . . . . . . . . . . . . . 46 160 B.22. Since draft-ietf-webdav-bind-23 . . . . . . . . . . . . . 46 161 B.23. Since draft-ietf-webdav-bind-24 . . . . . . . . . . . . . 47 162 B.24. Since draft-ietf-webdav-bind-25 . . . . . . . . . . . . . 47 163 Appendix C. Resolved issues (to be removed by RFC Editor 164 before publication) . . . . . . . . . . . . . . . . . 47 165 C.1. edit . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 166 C.2. locking-example . . . . . . . . . . . . . . . . . . . . . 47 167 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 168 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 50 170 1. Introduction 172 This specification extends the WebDAV Distributed Authoring Protocol 173 ([RFC4918]) to enable clients to create new access paths to existing 174 resources. This capability is useful for several reasons: 176 URIs of WebDAV-compliant resources are hierarchical and correspond to 177 a hierarchy of collections in resource space. The WebDAV Distributed 178 Authoring Protocol makes it possible to organize these resources into 179 hierarchies, placing them into groupings, known as collections, which 180 are more easily browsed and manipulated than a single flat 181 collection. However, hierarchies require categorization decisions 182 that locate resources at a single location in the hierarchy, a 183 drawback when a resource has multiple valid categories. For example, 184 in a hierarchy of vehicle descriptions containing collections for 185 cars and boats, a description of a combination car/boat vehicle could 186 belong in either collection. Ideally, the description should be 187 accessible from both. Allowing clients to create new URIs that 188 access the existing resource lets them put that resource into 189 multiple collections. 191 Hierarchies also make resource sharing more difficult, since 192 resources that have utility across many collections are still forced 193 into a single collection. For example, the mathematics department at 194 one university might create a collection of information on fractals 195 that contains bindings to some local resources, but also provides 196 access to some resources at other universities. For many reasons, it 197 may be undesirable to make physical copies of the shared resources on 198 the local server: to conserve disk space, to respect copyright 199 constraints, or to make any changes in the shared resources visible 200 automatically. Being able to create new access paths to existing 201 resources in other collections or even on other servers is useful for 202 this sort of case. 204 The BIND method defined here provides a mechanism for allowing 205 clients to create alternative access paths to existing WebDAV 206 resources. HTTP [RFC2616] and WebDAV [RFC4918] methods are able to 207 work because there are mappings between URIs and resources. A method 208 is addressed to a URI, and the server follows the mapping from that 209 URI to a resource, applying the method to that resource. Multiple 210 URIs may be mapped to the same resource, but until now there has been 211 no way for clients to create additional URIs mapped to existing 212 resources. 214 BIND lets clients associate a new URI with an existing WebDAV 215 resource, and this URI can then be used to submit requests to the 216 resource. Since URIs of WebDAV resources are hierarchical, and 217 correspond to a hierarchy of collections in resource space, the BIND 218 method also has the effect of adding the resource to a collection. 219 As new URIs are associated with the resource, it appears in 220 additional collections. 222 A BIND request does not create a new resource, but simply makes 223 available a new URI for submitting requests to an existing resource. 224 The new URI is indistinguishable from any other URI when submitting a 225 request to a resource. Only one round trip is needed to submit a 226 request to the intended target. Servers are required to enforce the 227 integrity of the relationships between the new URIs and the resources 228 associated with them. Consequently, it may be very costly for 229 servers to support BIND requests that cross server boundaries. 231 This specification is organized as follows. Section 1.1 defines 232 terminology used in the rest of the specification, while Section 2 233 overviews bindings. Section 3 defines the new properties needed to 234 support multiple bindings to the same resource. Section 4 specifies 235 the BIND method, used to create multiple bindings to the same 236 resource. Section 5 specifies the UNBIND method, used to remove a 237 binding to a resource. Section 6 specifies the REBIND method, used 238 to move a binding to another collection. 240 1.1. Terminology 242 The terminology used here follows and extends that in the WebDAV 243 Distributed Authoring Protocol specification [RFC4918]. 245 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 246 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 247 document are to be interpreted as described in [RFC2119]. 249 This document uses XML DTD fragments ([XML]) as a notational 250 convention, using the rules defined in Section 17 of [RFC4918]. 252 URI Mapping 254 A relation between an absolute URI and a resource. For an 255 absolute URI U and the resource it identifies R, the URI mapping 256 can be thought of as (U => R). Since a resource can represent 257 items that are not network retrievable, as well as those that are, 258 it is possible for a resource to have zero, one, or many URI 259 mappings. Mapping a resource to an "http" scheme URI makes it 260 possible to submit HTTP protocol requests to the resource using 261 the URI. 263 Path Segment 265 Informally, the characters found between slashes ("/") in a URI. 266 Formally, as defined in Section 3.3 of [RFC3986]. 268 Binding 270 A relation between a single path segment (in a collection) and a 271 resource. A binding is part of the state of a collection. If two 272 different collections contain a binding between the same path 273 segment and the same resource, these are two distinct bindings. 274 So for a collection C, a path segment S, and a resource R, the 275 binding can be thought of as C:(S -> R). Bindings create URI 276 mappings, and hence allow requests to be sent to a single resource 277 from multiple locations in a URI namespace. For example, given a 278 collection C (accessible through the URI 279 http://www.example.com/CollX), a path segment S (equal to 280 "foo.html"), and a resource R, then creating the binding C: (S -> 281 R) makes it possible to use the URI 282 http://www.example.com/CollX/foo.html to access R. 284 Collection 286 A resource that contains, as part of its state, a set of bindings 287 that identify internal member resources. 289 Internal Member URI 291 The URI that identifies an internal member of a collection, and 292 that consists of the URI for the collection, followed by a slash 293 character ('/'), followed by the path segment of the binding for 294 that internal member. 296 Binding Integrity 298 The property of a binding that says that: 300 * the binding continues to exist, and 302 * the identity of the resource identified by that binding does 303 not change 305 unless an explicit request is executed that is defined to delete 306 that binding (examples of requests that delete a binding are 307 DELETE, MOVE, and - defined later on - UNBIND, and REBIND). 309 1.2. Method Preconditions and Postconditions 311 See Section 16 of [RFC4918] for the definitions of "precondition" and 312 "postcondition". 314 2. Overview of Bindings 316 Bindings are part of the state of a collection. They define the 317 internal members of the collection, and the names of those internal 318 members. 320 Bindings are added and removed by a variety of existing HTTP methods. 321 A method that creates a new resource, such as PUT, COPY, and MKCOL, 322 adds a binding. A method that deletes a resource, such as DELETE, 323 removes a binding. A method that moves a resource (e.g. MOVE) both 324 adds a binding (in the destination collection) and removes a binding 325 (in the source collection). The BIND method introduced here provides 326 a mechanism for adding a second binding to an existing resource. 327 There is no difference between an initial binding added by PUT, COPY, 328 or MKCOL, and additional bindings added with BIND. 330 It would be very undesirable if one binding could be destroyed as a 331 side effect of operating on the resource through a different binding. 332 In particular, the removal of one binding to a resource (e.g. with a 333 DELETE or a MOVE) MUST NOT disrupt another binding to that resource, 334 e.g. by turning that binding into a dangling path segment. The 335 server MUST NOT reclaim system resources after removing one binding, 336 while other bindings to the resource remain. In other words, the 337 server MUST maintain the integrity of a binding. It is permissible, 338 however, for future method definitions (e.g., a DESTROY method) to 339 have semantics that explicitly remove all bindings and/or immediately 340 reclaim system resources. 342 2.1. Bindings to Collections 344 Creating a new binding to a collection makes each resource associated 345 with a binding in that collection accessible via a new URI, and thus 346 creates new URI mappings to those resources but no new bindings. 348 For example, suppose a new binding CollY is created for collection C1 349 in the figure below. It immediately becomes possible to access 350 resource R1 using the URI /CollY/x.gif and to access resource R2 351 using the URI /CollY/y.jpg, but no new bindings for these child 352 resources were created. This is because bindings are part of the 353 state of a collection, and associate a URI that is relative to that 354 collection with its target resource. No change to the bindings in 355 Collection C1 is needed to make its children accessible using /CollY/ 356 x.gif and /CollY/y.jpg. 358 +-------------------------+ 359 | Root Collection | 360 | bindings: | 361 | CollX CollY | 362 +-------------------------+ 363 | / 364 | / 365 | / 366 +------------------+ 367 | Collection C1 | 368 | bindings: | 369 | x.gif y.jpg | 370 +------------------+ 371 | \ 372 | \ 373 | \ 374 +-------------+ +-------------+ 375 | Resource R1 | | Resource R2 | 376 +-------------+ +-------------+ 378 2.1.1. Bind Loops 380 Bindings to collections can result in loops ("cycles"), which servers 381 MUST detect when processing "Depth: infinity" requests. It is 382 sometimes possible to complete an operation in spite of the presence 383 of a loop. For instance, a PROPFIND can still succeed if the server 384 uses the new status code 208 (Already Reported) defined in 385 Section 7.1. 387 However, the 506 (Loop Detected) status code is defined in 388 Section 7.2 for use in contexts where an operation is terminated 389 because a loop was encountered. 391 Support for loops is OPTIONAL: servers MAY reject requests that would 392 lead to the creation of a bind loop (see DAV:cycle-allowed 393 precondition defined in Section 4). 395 2.2. URI Mappings Created by a new Binding 397 Suppose a binding from "Binding-Name" to resource R is to be added to 398 a collection, C. Then if C-MAP is the set of URIs that were mapped to 399 C before the BIND request, then for each URI "C-URI" in C-MAP, the 400 URI "C-URI/Binding-Name" is mapped to resource R following the BIND 401 request. 403 For example, if a binding from "foo.html" to R is added to a 404 collection C, and if the following URIs are mapped to C: 406 http://www.example.com/A/1/ 407 http://example.com/A/one/ 409 then the following new mappings to R are introduced: 411 http://www.example.com/A/1/foo.html 412 http://example.com/A/one/foo.html 414 Note that if R is a collection, additional URI mappings are created 415 to the descendents of R. Also, note that if a binding is made in 416 collection C to C itself (or to a parent of C), an infinite number of 417 mappings are introduced. 419 For example, if a binding from "myself" to C is then added to C, the 420 following infinite number of additional mappings to C are introduced: 422 http://www.example.com/A/1/myself 423 http://www.example.com/A/1/myself/myself 424 ... 426 and the following infinite number of additional mappings to R are 427 introduced: 429 http://www.example.com/A/1/myself/foo.html 430 http://www.example.com/A/1/myself/myself/foo.html 431 ... 433 2.3. COPY and Bindings 435 As defined in Section 9.8 of [RFC4918], COPY causes the resource 436 identified by the Request-URI to be duplicated, and makes the new 437 resource accessible using the URI specified in the Destination 438 header. Upon successful completion of a COPY, a new binding is 439 created between the last path segment of the Destination header, and 440 the destination resource. The new binding is added to its parent 441 collection, identified by the Destination header minus its final 442 segment. 444 The following figure shows an example: Suppose that a COPY is issued 445 to URI-3 for resource R (which is also mapped to URI-1 and URI-2), 446 with the Destination header set to URI-X. After successful 447 completion of the COPY operation, resource R is duplicated to create 448 resource R', and a new binding has been created which creates at 449 least the URI mapping between URI-X and the new resource (although 450 other URI mappings may also have been created). 452 URI-1 URI-2 URI-3 URI-X 453 | | | | 454 | | | <---- URI Mappings ----> | 455 | | | | 456 +---------------------+ +------------------------+ 457 | Resource R | | Resource R' | 458 +---------------------+ +------------------------+ 460 It might be thought that a COPY request with "Depth: 0" on a 461 collection would duplicate its bindings, since bindings are part of 462 the collection's state. This is not the case, however. The 463 definition of Depth in [RFC4918] makes it clear that a "Depth: 0" 464 request does not apply to a collection's members. Consequently, a 465 COPY with "Depth: 0" does not duplicate the bindings contained by the 466 collection. 468 If a COPY request causes an existing resource to be updated, the 469 bindings to that resource MUST be unaffected by the COPY request. 470 Using the preceding example, suppose that a COPY request is issued to 471 URI-X for resource R', with the Destination header set to URI-2. The 472 content and dead properties of resource R would be updated to be a 473 copy of those of resource R', but the mappings from URI-1, URI-2, and 474 URI-3 to resource R remain unaffected. If because of multiple 475 bindings to a resource, more than one source resource updates a 476 single destination resource, the order of the updates is server 477 defined (see Section 2.3.2 for an example). 479 If a COPY request would cause a new resource to be created as a copy 480 of an existing resource, and that COPY request has already created a 481 copy of that existing resource, the COPY request instead creates 482 another binding to the previous copy, instead of creating a new 483 resource (see Section 2.3.3 for an example). 485 2.3.1. Example: COPY with 'Depth: infinity' in Presence of Bind Loops 487 As an example of how COPY with Depth infinity would work in the 488 presence of bindings, consider the following collection: 490 +------------------+ 491 | Root Collection | 492 | bindings: | 493 | CollX | 494 +------------------+ 495 | 496 | 497 +-------------------------------+ 498 | Collection C1 |<-------+ 499 | bindings: | | 500 | x.gif CollY | | 501 +-------------------------------+ | 502 | \ (creates loop) | 503 | \ | 504 +-------------+ +------------------+ | 505 | Resource R1 | | Collection C2 | | 506 +-------------+ | bindings: | | 507 | y.gif CollZ | | 508 +------------------+ | 509 | | | 510 | +--------+ 511 | 512 +-------------+ 513 | Resource R2 | 514 +-------------+ 516 If a COPY with Depth infinity is submitted to /CollX, with 517 destination of /CollA, the outcome of the copy operation is: 519 +------------------+ 520 | Root Collection | 521 | bindings: | 522 | CollX CollA | 523 +------------------+ 524 | | 525 | +---------------------------+ 526 | | 527 +-------------------+ | 528 | Collection C1 |<------------------+ | 529 | bindings: | | | 530 | x.gif CollY | | | 531 +-------------------+ | | 532 | \ (creates loop) | | 533 | \ | | 534 +-------------+ +-----------------+ | | 535 | Resource R1 | | Collection C2 | | | 536 +-------------+ | bindings: | | | 537 | y.gif CollZ | | | 538 +-----------------+ | | 539 | | | | 540 | +-------+ | 541 | | 542 +-------------+ | 543 | Resource R2 | | 544 +-------------+ | 545 | 546 +-------------------------------+ 547 | 548 +-------------------+ 549 | Collection C3 |<------------------+ 550 | bindings: | | 551 | x.gif CollY | | 552 +-------------------+ | 553 | \ (creates loop) | 554 | \ | 555 +-------------+ +-----------------+ | 556 | Resource R3 | | Collection C4 | | 557 +-------------+ | bindings: | | 558 | y.gif CollZ | | 559 +-----------------+ | 560 | | | 561 | +-------+ 562 | 563 +-------------+ 564 | Resource R4 | 565 +-------------+ 567 2.3.2. Example: COPY updating multiple Bindings 569 Given the following collection hierarchy: 571 +------------------+ 572 | Root Collection | 573 | bindings: | 574 | CollX CollY | 575 +------------------+ 576 / \ 577 / \ 578 / \ 579 +--------------------------+ +-----------------+ 580 | Collection C1 | | Collection C2 | 581 | bindings: | | bindings: | 582 | x.gif y.gif | | x.gif y.gif | 583 +--------------------------+ +-----------------+ 584 | | | | 585 | | | | 586 +-------------+ +-------------+ +-------------+ 587 | Resource R1 | | Resource R2 | | Resource R3 | 588 +-------------+ +-------------+ +-------------+ 590 A COPY of /CollX with Depth infinity to /CollY will not result in a 591 changed hierarchy, and Resource R3 will be updated with the content 592 of either Resource R1 or Resource R2. 594 2.3.3. Example: COPY with 'Depth: infinity' with Multiple Bindings to a 595 Leaf Resource 597 Given the following collection hierarchy: 599 +------------------+ 600 | Root Collection | 601 | bindings: | 602 | CollX | 603 +------------------+ 604 | 605 | 606 | 607 +----------------+ 608 | Collection C1 | 609 | bindings: | 610 | x.gif y.gif | 611 +----------------+ 612 | | 613 | | 614 +-------------+ 615 | Resource R1 | 616 +-------------+ 618 A COPY of /CollX with Depth infinity to /CollY results in the 619 following collection hierarchy: 621 +------------------+ 622 | Root Collection | 623 | bindings: | 624 | CollX CollY | 625 +------------------+ 626 | \ 627 | \ 628 | \ 629 +----------------+ +-----------------+ 630 | Collection C1 | | Collection C2 | 631 | bindings: | | bindings: | 632 | x.gif y.gif | | x.gif y.gif | 633 +----------------+ +-----------------+ 634 | | | | 635 | | | | 636 +-------------+ +-------------+ 637 | Resource R1 | | Resource R2 | 638 +-------------+ +-------------+ 640 2.4. DELETE and Bindings 642 When there are multiple bindings to a resource, a DELETE applied to 643 that resource MUST NOT remove any bindings to that resource other 644 than the one identified by the Request-URI. For example, suppose the 645 collection identified by the URI "/a" has a binding named "x" to a 646 resource R, and another collection identified by "/b" has a binding 647 named "y" to the same resource R. Then a DELETE applied to "/a/x" 648 removes the binding named "x" from "/a" but MUST NOT remove the 649 binding named "y" from "/b" (i.e. after the DELETE, "/y/b" continues 650 to identify the resource R). 652 When DELETE is applied to a collection, it MUST NOT modify the 653 membership of any other collection that is not itself a member of the 654 collection being deleted. For example, if both "/a/.../x" and 655 "/b/.../y" identify the same collection, C, then applying DELETE to 656 "/a" must not delete an internal member from C or from any other 657 collection that is a member of C, because that would modify the 658 membership of "/b". 660 If a collection supports the UNBIND method (see Section 5), a DELETE 661 of an internal member of a collection MAY be implemented as an UNBIND 662 request. In this case, applying DELETE to a Request-URI has the 663 effect of removing the binding identified by the final segment of the 664 Request-URI from the collection identified by the Request-URI minus 665 its final segment. Although [RFC4918] allows a DELETE to be a non- 666 atomic operation, when the DELETE operation is implemented as an 667 UNBIND, the operation is atomic. In particular, a DELETE on a 668 hierarchy of resources is simply the removal of a binding to the 669 collection identified by the Request-URI. 671 2.5. MOVE and Bindings 673 When MOVE is applied to a resource, the other bindings to that 674 resource MUST be unaffected, and if the resource being moved is a 675 collection, the bindings to any members of that collection MUST be 676 unaffected. Also, if MOVE is used with Overwrite:T to delete an 677 existing resource, the constraints specified for DELETE apply. 679 If the destination collection of a MOVE request supports the REBIND 680 method (see Section 6), a MOVE of a resource into that collection MAY 681 be implemented as a REBIND request. Although [RFC4918] allows a MOVE 682 to be a non-atomic operation, when the MOVE operation is implemented 683 as a REBIND, the operation is atomic. In particular, applying a MOVE 684 to a Request-URI and a Destination URI has the effect of removing a 685 binding to a resource (at the Request-URI), and creating a new 686 binding to that resource (at the Destination URI). Even when the 687 Request-URI identifies a collection, the MOVE operation involves only 688 removing one binding to that collection and adding another. 690 2.5.1. Example: Simple MOVE 692 As an example, suppose that a MOVE is issued to URI-3 for resource R 693 below (which is also mapped to URI-1 and URI-2), with the Destination 694 header set to URI-X. After successful completion of the MOVE 695 operation, a new binding has been created which creates the URI 696 mapping between URI-X and resource R. The binding corresponding to 697 the final segment of URI-3 has been removed, which also causes the 698 URI mapping between URI-3 and R to be removed. If resource R were a 699 collection, old URI-3 based mappings to members of R would have been 700 removed, and new URI-X based mappings to members of R would have been 701 created. 703 >> Before Request: 705 URI-1 URI-2 URI-3 706 | | | 707 | | | <---- URI Mappings 708 | | | 709 +---------------------+ 710 | Resource R | 711 +---------------------+ 713 >> After Request: 715 URI-1 URI-2 URI-X 716 | | | 717 | | | <---- URI Mappings 718 | | | 719 +---------------------+ 720 | Resource R | 721 +---------------------+ 723 2.5.2. Example: MOVE Request causing a Bind Loop 725 Note that in the presence of collection bindings, a MOVE request can 726 cause the creating of a bind loop. 728 Consider a the top level collections C1 and C2 with URIs "/CollW/" 729 and "/CollX/". C1 also contains an additional binding named "CollY" 730 to C2: 732 +------------------+ 733 | Root Collection | 734 | bindings: | 735 | CollW CollX | 736 +------------------+ 737 | | 738 | | 739 +------------------+ | 740 | Collection C1 | | 741 | bindings: | | 742 | CollY | | 743 +------------------+ | 744 | | 745 | | 746 +------------------+ 747 | Collection C2 | 748 | | 749 | | 750 +------------------+ 752 In this case, the MOVE request below would cause a bind loop: 754 >> Request: 756 MOVE /CollW HTTP/1.1 757 Host: example.com 758 Destination: /CollX/CollZ 759 If the request succeeded, the resulting state would be: 761 +------------------+ 762 | Root Collection | 763 | bindings: | 764 | CollX | 765 +------------------+ 766 | 767 | 768 +------------------+ | 769 | Collection C1 | | 770 +----> | bindings: | | 771 | | CollY | | 772 | +------------------+ | 773 | | | 774 | | | 775 | +------------------+ 776 | | Collection C2 | 777 | | bindings: | 778 | | CollZ | 779 | +------------------+ 780 | | 781 | | 782 +-------------------+ 784 2.6. PROPFIND and Bindings 786 Consistent with [RFC4918], the value of a dead property MUST be 787 independent of the number of bindings to its host resource or of the 788 path submitted to PROPFIND. On the other hand, the behavior for each 789 live property depends on its individual definition (for example, see 790 [RFC3744], Section 5, paragraph 2 for a case where the value is 791 independent of path and bindings, and [RFC4918], Section 8.8 for a 792 discussion about the live properties DAV:getetag and DAV: 793 getlastmodified, which may behave differently). 795 2.7. Determining Whether Two Bindings Are to the Same Resource 797 It is useful to have some way of determining whether two bindings are 798 to the same resource. Two resources might have identical contents 799 and properties, but not be the same resource (e.g. an update to one 800 resource does not affect the other resource). 802 The REQUIRED DAV:resource-id property defined in Section 3.1 is a 803 resource identifier, which MUST be unique across all resources for 804 all time. If the values of DAV:resource-id returned by PROPFIND 805 requests through two bindings are identical character by character, 806 the client can be assured that the two bindings are to the same 807 resource. 809 The DAV:resource-id property is created, and its value assigned, when 810 the resource is created. The value of DAV:resource-id MUST NOT be 811 changed. Even after the resource is no longer accessible through any 812 URI, that value MUST NOT be reassigned to another resource's DAV: 813 resource-id property. 815 Any method that creates a new resource MUST assign a new, unique 816 value to its DAV:resource-id property. For example, a PUT applied to 817 a null resource, COPY (when not overwriting an existing target) and 818 CHECKIN (see [RFC3253], Section 4.4) must assign a new, unique value 819 to the DAV:resource-id property of the new resource they create. 821 On the other hand, any method that affects an existing resource must 822 not change the value of its DAV:resource-id property. Specifically, 823 a PUT or a COPY that updates an existing resource must not change the 824 value of its DAV:resource-id property. A REBIND, since it does not 825 create a new resource, but only changes the location of an existing 826 resource, must not change the value of the DAV:resource-id property. 828 2.8. Discovering the Bindings to a Resource 830 An OPTIONAL DAV:parent-set property on a resource provides a list of 831 the bindings that associate a collection and a URI segment with that 832 resource. If the DAV:parent-set property exists on a given resource, 833 it MUST contain a complete list of all bindings to that resource that 834 the client is authorized to see. When deciding whether to support 835 the DAV:parent-set property, server implementers / administrators 836 should balance the benefits it provides against the cost of 837 maintaining the property and the security risks enumerated in 838 Sections 11.4 and 11.5. 840 3. Properties 842 The bind feature introduces the properties defined below. 844 A DAV:allprop PROPFIND request SHOULD NOT return any of the 845 properties defined by this document. This allows a binding server to 846 perform efficiently when a naive client, which does not understand 847 the cost of asking a server to compute all possible live properties, 848 issues a DAV:allprop PROPFIND request. 850 3.1. DAV:resource-id Property 852 The DAV:resource-id property is a REQUIRED property that enables 853 clients to determine whether two bindings are to the same resource. 855 The value of DAV:resource-id is a URI, and may use any registered URI 856 scheme that guarantees the uniqueness of the value across all 857 resources for all time (e.g. the urn:uuid: URN namespace defined in 858 [RFC4122] or the opaquelocktoken: URI scheme defined in [RFC4918]). 860 862 3.2. DAV:parent-set Property 864 The DAV:parent-set property is an OPTIONAL property that enables 865 clients to discover what collections contain a binding to this 866 resource (i.e. what collections have that resource as an internal 867 member). It contains an href/segment pair for each collection that 868 has a binding to the resource. The href identifies the collection, 869 and the segment identifies the binding name of that resource in that 870 collection. 872 A given collection MUST appear only once in the DAV:parent-set for 873 any given binding, even if there are multiple URI mappings to that 874 collection. 876 877 878 879 882 3.2.1. Example for DAV:parent-set Property 884 For example, if collection C1 is mapped to both /CollX and /CollY, 885 and C1 contains a binding named "x.gif" to a resource R1, then either 886 [/CollX, x.gif] or [/CollY, x.gif] can appear in the DAV:parent-set 887 of R1, but not both. But if C1 also had a binding named "y.gif" to 888 R1, then there would be two entries for C1 in the DAV:parent-set of 889 R1 (i.e. both [/CollX, x.gif] and [/CollX, y.gif] or, alternatively, 890 both [/CollY, x.gif] and [/CollY, y.gif]). 892 +-------------------------+ 893 | Root Collection | 894 | bindings: | 895 | CollX CollY | 896 +-------------------------+ 897 | / 898 | / 899 | / 900 +-----------------+ 901 | Collection C1 | 902 | bindings: | 903 | x.gif y.gif | 904 +-----------------+ 905 | | 906 | | 907 | | 908 +-------------+ 909 | Resource R1 | 910 +-------------+ 912 In this case, one possible value for DAV:parent-set property on 913 "/CollX/x.gif" would be: 915 916 917 /CollX 918 x.gif 919 920 921 /CollX 922 y.gif 923 924 926 4. BIND Method 928 The BIND method modifies the collection identified by the Request- 929 URI, by adding a new binding from the segment specified in the BIND 930 body to the resource identified in the BIND body. 932 If a server cannot guarantee the integrity of the binding, the BIND 933 request MUST fail. Note that it is especially difficult to maintain 934 the integrity of cross-server bindings. Unless the server where the 935 resource resides knows about all bindings on all servers to that 936 resource, it may unwittingly destroy the resource or make it 937 inaccessible without notifying another server that manages a binding 938 to the resource. For example, if server A permits creation of a 939 binding to a resource on server B, server A must notify server B 940 about its binding and must have an agreement with B that B will not 941 destroy the resource while A's binding exists. Otherwise server B 942 may receive a DELETE request that it thinks removes the last binding 943 to the resource and destroy the resource while A's binding still 944 exists. The precondition DAV:cross-server-binding is defined below 945 for cases where servers fail cross-server BIND requests because they 946 cannot guarantee the integrity of cross-server bindings. 948 By default, if there already is a binding for the specified segment 949 in the collection, the new binding replaces the existing binding. 950 This default binding replacement behavior can be overridden using the 951 Overwrite header defined in Section 10.6 of [RFC4918]. 953 If a BIND request fails, the server state preceding the request MUST 954 be restored. This method is unsafe and idempotent (see [RFC2616], 955 Section 9.1). 957 Marshalling: 959 The request MAY include an Overwrite header. 961 The request body MUST be a DAV:bind XML element. 963 965 If the request succeeds, the server MUST return 201 (Created) when 966 a new binding was created and 200 (OK) or 204 (No Content) when an 967 existing binding was replaced. 969 If a response body for a successful request is included, it MUST 970 be a DAV:bind-response XML element. Note that this document does 971 not define any elements for the BIND response body, but the DAV: 972 bind-response element is defined to ensure interoperability 973 between future extensions that do define elements for the BIND 974 response body. 976 978 Preconditions: 980 (DAV:bind-into-collection): The Request-URI MUST identify a 981 collection. 983 (DAV:bind-source-exists): The DAV:href element MUST identify a 984 resource. 986 (DAV:binding-allowed): The resource identified by the DAV:href 987 supports multiple bindings to it. 989 (DAV:cross-server-binding): If the resource identified by the DAV: 990 href element in the request body is on another server from the 991 collection identified by the Request-URI, the server MUST support 992 cross-server bindings (servers that do not support cross-server 993 bindings can use this condition code to signal the client exactly 994 why the request failed). 996 (DAV:name-allowed): The name specified by the DAV:segment is 997 available for use as a new binding name. 999 (DAV:can-overwrite): If the collection already contains a binding 1000 with the specified path segment, and if an Overwrite header is 1001 included, the value of the Overwrite header MUST be "T". 1003 (DAV:cycle-allowed): If the DAV:href element identifies a 1004 collection, and if the Request-URI identifies a collection that is 1005 a member of that collection, the server MUST support cycles in the 1006 URI namespace (servers that do not support cycles can use this 1007 condition code to signal the client exactly why the request 1008 failed). 1010 (DAV:locked-update-allowed): If the collection identified by the 1011 Request-URI is write-locked, then the appropriate token MUST be 1012 specified in an If request header. 1014 (DAV:locked-overwrite-allowed): If the collection already contains 1015 a binding with the specified path segment, and if that binding is 1016 protected by a write-lock, then the appropriate token MUST be 1017 specified in an If request header. 1019 Postconditions: 1021 (DAV:new-binding): The collection MUST have a binding that maps 1022 the segment specified in the DAV:segment element in the request 1023 body, to the resource identified by the DAV:href element in the 1024 request body. 1026 4.1. Example: BIND 1028 >> Request: 1030 BIND /CollY HTTP/1.1 1031 Host: www.example.com 1032 Content-Type: application/xml; charset="utf-8" 1033 Content-Length: 172 1035 1036 1037 bar.html 1038 http://www.example.com/CollX/foo.html 1039 1041 >> Response: 1043 HTTP/1.1 201 Created 1044 Location: http://www.example.com/CollY/bar.html 1046 The server added a new binding to the collection, 1047 "http://www.example.com/CollY", associating "bar.html" with the 1048 resource identified by the URI 1049 "http://www.example.com/CollX/foo.html". Clients can now use the URI 1050 "http://www.example.com/CollY/bar.html" to submit requests to that 1051 resource. 1053 5. UNBIND Method 1055 The UNBIND method modifies the collection identified by the Request- 1056 URI, by removing the binding identified by the segment specified in 1057 the UNBIND body. 1059 Once a resource is unreachable by any URI mapping, the server MAY 1060 reclaim system resources associated with that resource. If UNBIND 1061 removes a binding to a resource, but there remain URI mappings to 1062 that resource, the server MUST NOT reclaim system resources 1063 associated with the resource. 1065 If an UNBIND request fails, the server state preceding the request 1066 MUST be restored. This method is unsafe and idempotent (see 1067 [RFC2616], Section 9.1). 1069 Marshalling: 1071 The request body MUST be a DAV:unbind XML element. 1073 1075 If the request succeeds, the server MUST return 200 (OK) or 204 1076 (No Content) when the binding was successfully deleted. 1078 If a response body for a successful request is included, it MUST 1079 be a DAV:unbind-response XML element. Note that this document 1080 does not define any elements for the UNBIND response body, but the 1081 DAV:unbind-response element is defined to ensure interoperability 1082 between future extensions that do define elements for the UNBIND 1083 response body. 1085 1087 Preconditions: 1089 (DAV:unbind-from-collection): The Request-URI MUST identify a 1090 collection. 1092 (DAV:unbind-source-exists): The DAV:segment element MUST identify 1093 a binding in the collection identified by the Request-URI. 1095 (DAV:locked-update-allowed): If the collection identified by the 1096 Request-URI is write-locked, then the appropriate token MUST be 1097 specified in the request. 1099 (DAV:protected-url-deletion-allowed): If the binding identified by 1100 the segment is protected by a write-lock, then the appropriate 1101 token MUST be specified in the request. 1103 Postconditions: 1105 (DAV:binding-deleted): The collection MUST NOT have a binding for 1106 the segment specified in the DAV:segment element in the request 1107 body. 1109 (DAV:lock-deleted): If the internal member URI of the binding 1110 specified by the Request-URI and the DAV:segment element in the 1111 request body was protected by a write-lock at the time of the 1112 request, that write-lock must have been deleted by the request. 1114 5.1. Example: UNBIND 1116 >> Request: 1118 UNBIND /CollX HTTP/1.1 1119 Host: www.example.com 1120 Content-Type: application/xml; charset="utf-8" 1121 Content-Length: 117 1123 1124 1125 foo.html 1126 1128 >> Response: 1130 HTTP/1.1 200 OK 1132 The server removed the binding named "foo.html" from the collection, 1133 "http://www.example.com/CollX". A request to the resource named 1134 "http://www.example.com/CollX/foo.html" will return a 404 (Not Found) 1135 response. 1137 6. REBIND Method 1139 The REBIND method removes a binding to a resource from a collection, 1140 and adds a binding to that resource into the collection identified by 1141 the Request-URI. The request body specifies the binding to be added 1142 (segment) and the old binding to be removed (href). It is 1143 effectively an atomic form of a MOVE request, and MUST be treated the 1144 same way as MOVE for the purpose of determining access permissions. 1146 If a REBIND request fails, the server state preceding the request 1147 MUST be restored. This method is unsafe and idempotent (see 1148 [RFC2616], Section 9.1). 1150 Marshalling: 1152 The request MAY include an Overwrite header. 1154 The request body MUST be a DAV:rebind XML element. 1156 1158 If the request succeeds, the server MUST return 201 (Created) when 1159 a new binding was created and 200 (OK) or 204 (No Content) when an 1160 existing binding was replaced. 1162 If a response body for a successful request is included, it MUST 1163 be a DAV:rebind-response XML element. Note that this document 1164 does not define any elements for the REBIND response body, but the 1165 DAV:rebind-response element is defined to ensure interoperability 1166 between future extensions that do define elements for the REBIND 1167 response body. 1169 1171 Preconditions: 1173 (DAV:rebind-into-collection): The Request-URI MUST identify a 1174 collection. 1176 (DAV:rebind-source-exists): The DAV:href element MUST identify a 1177 resource. 1179 (DAV:cross-server-binding): If the resource identified by the DAV: 1180 href element in the request body is on another server from the 1181 collection identified by the Request-URI, the server MUST support 1182 cross-server bindings (servers that do not support cross-server 1183 bindings can use this condition code to signal the client exactly 1184 why the request failed). 1186 (DAV:name-allowed): The name specified by the DAV:segment is 1187 available for use as a new binding name. 1189 (DAV:can-overwrite): If the collection already contains a binding 1190 with the specified path segment, and if an Overwrite header is 1191 included, the value of the Overwrite header MUST be "T". 1193 (DAV:cycle-allowed): If the DAV:href element identifies a 1194 collection, and if the Request-URI identifies a collection that is 1195 a member of that collection, the server MUST support cycles in the 1196 URI namespace (servers that do not support cycles can use this 1197 condition code to signal the client exactly why the request 1198 failed). 1200 (DAV:locked-update-allowed): If the collection identified by the 1201 Request-URI is write-locked, then the appropriate token MUST be 1202 specified in the request. 1204 (DAV:protected-url-modification-allowed): If the collection 1205 identified by the Request-URI already contains a binding with the 1206 specified path segment, and if that binding is protected by a 1207 write-lock, then the appropriate token MUST be specified in the 1208 request. 1210 (DAV:locked-source-collection-update-allowed): If the collection 1211 identified by the parent collection prefix of the DAV:href URI is 1212 write-locked, then the appropriate token MUST be specified in the 1213 request. 1215 (DAV:protected-source-url-deletion-allowed): If the DAV:href URI 1216 is protected by a write lock, then the appropriate token MUST be 1217 specified in the request. 1219 Postconditions: 1221 (DAV:new-binding): The collection MUST have a binding that maps 1222 the segment specified in the DAV:segment element in the request 1223 body, to the resource that was identified by the DAV:href element 1224 in the request body. 1226 (DAV:binding-deleted): The URL specified in the DAV:href element 1227 in the request body MUST NOT be mapped to a resource. 1229 (DAV:lock-deleted): If the URL specified in the DAV:href element 1230 in the request body was protected by a write-lock at the time of 1231 the request, that write-lock must have been deleted by the 1232 request. 1234 6.1. Example: REBIND 1236 >> Request: 1238 REBIND /CollX HTTP/1.1 1239 Host: www.example.com 1240 Content-Type: application/xml; charset="utf-8" 1241 Content-Length: 176 1243 1244 1245 foo.html 1246 http://www.example.com/CollY/bar.html 1247 1249 >> Response: 1251 HTTP/1.1 200 OK 1253 The server added a new binding to the collection, 1254 "http://www.example.com/CollX", associating "foo.html" with the 1255 resource identified by the URI 1256 "http://www.example.com/CollY/bar.html", and removes the binding 1257 named "bar.html" from the collection identified by the URI 1258 "http://www.example.com/CollY". Clients can now use the URI 1259 "http://www.example.com/CollX/foo.html" to submit requests to that 1260 resource, and requests on the URI 1261 "http://www.example.com/CollY/bar.html" will fail with a 404 (Not 1262 Found) response. 1264 6.2. Example: REBIND in Presence of Locks and Bind Loops 1266 To illustrate the effects of locks and bind loops on a REBIND 1267 operation, consider the following collection: 1269 +------------------+ 1270 | Root Collection | 1271 | bindings: | 1272 | CollW | 1273 +------------------+ 1274 | 1275 | 1276 | 1277 +-------------------------------+ 1278 | Collection C1 |<--------+ 1279 | LOCKED infinity | | 1280 | (lock token L1) | | 1281 | bindings: | | 1282 | CollX CollY | | 1283 +-------------------------------+ | 1284 | | | 1285 | | (creates loop) | 1286 | | | 1287 +-----------------+ +------------------+ | 1288 | Collection C2 | | Collection C3 | | 1289 | (inherit lock) | | (inherit lock) | | 1290 | (lock token L1) | | (lock token L1) | | 1291 | bindings: | | bindings: | | 1292 | {none} | | y.gif CollZ | | 1293 +-----------------+ +------------------+ | 1294 | | | 1295 | +-----+ 1296 | 1297 +---------------------------+ 1298 | Resource R2 | 1299 | (lock inherited from C1) | 1300 | (lock token L1) | 1301 +---------------------------+ 1303 (where L1 is "urn:uuid:f92d4fae-7012-11ab-a765-00c0ca1f6bf9"). 1305 Note that the binding between CollZ and C1 creates a loop in the 1306 containment hierarchy. Servers are not required to support such 1307 loops, though the server in this example does. 1309 The REBIND request below will remove the segment "CollZ" from C3 and 1310 add a new binding from "CollA" to the collection C2. 1312 REBIND /CollW/CollX HTTP/1.1 1313 Host: www.example.com 1314 If: () 1315 Content-Type: application/xml; charset="utf-8" 1316 Content-Length: 152 1318 1319 1320 CollA 1321 /CollW/CollY/CollZ 1322 1323 The outcome of the REBIND operation is: 1325 +------------------+ 1326 | Root Collection | 1327 | bindings: | 1328 | CollW | 1329 +------------------+ 1330 | 1331 | 1332 | 1333 +-------------------------------+ 1334 | Collection C1 | 1335 | LOCKED infinity | 1336 | (lock token L1) | 1337 | bindings: | 1338 | CollX CollY | 1339 +-------------------------------+ 1340 | ^ | 1341 | | | 1342 +-----------------+ | +------------------+ 1343 | Collection C2 | | | Collection C3 | 1344 |(inherited lock) | | | (inherited lock) | 1345 |(lock token L1) | | | (lock token L1) | 1346 | bindings: | | | bindings: | 1347 | CollA | | | y.gif | 1348 +-----------------+ | +------------------+ 1349 | | | 1350 +---------------+ | 1351 (creates loop) | 1352 +---------------------------+ 1353 | Resource R2 | 1354 | (inherited lock from C1) | 1355 | (lock token L1) | 1356 +---------------------------+ 1358 7. Additional Status Codes 1360 7.1. 208 Already Reported 1362 The 208 (Already Reported) status code can be used inside a DAV: 1363 propstat response element to avoid enumerating the internal members 1364 of multiple bindings to the same collection repeatedly. For each 1365 binding to a collection inside the request's scope, only one will be 1366 reported with a 200 status, while subsequent DAV:response elements 1367 for all other bindings will use the 208 status, and no DAV:response 1368 elements for their descendants are included. 1370 Note that the 208 status will only occur for "Depth: infinity" 1371 requests, and that it is of particular importance when the multiple 1372 collection bindings cause a bind loop as discussed in Section 2.2. 1374 A client can request the DAV:resource-id property in a PROPFIND 1375 request to guarantee that they can accurately reconstruct the binding 1376 structure of a collection with multiple bindings to a single 1377 resource. 1379 For backward compatibility with clients not aware of the 208 status 1380 code appearing in multistatus response bodies, it SHOULD NOT be used 1381 unless the client has signalled support for this specification using 1382 the "DAV" request header (see Section 8.2). Instead, a 506 status 1383 should be returned when a binding loop is discovered. This allows 1384 the server to return the 506 as the top level return status, if it 1385 discovers it before it started the response, or in the middle of a 1386 multistatus, if it discovers it in the middle of streaming out a 1387 multistatus response. 1389 7.1.1. Example: PROPFIND by Bind-Aware Client 1391 For example, consider a PROPFIND request on /Coll (bound to 1392 collection C), where the members of /Coll are /Coll/Foo (bound to 1393 resource R) and /Coll/Bar (bound to collection C). 1395 >> Request: 1397 PROPFIND /Coll/ HTTP/1.1 1398 Host: www.example.com 1399 Depth: infinity 1400 DAV: bind 1401 Content-Type: application/xml; charset="utf-8" 1402 Content-Length: 152 1404 1405 1406 1407 1408 1409 1410 1412 >> Response: 1414 HTTP/1.1 207 Multi-Status 1415 Content-Type: application/xml; charset="utf-8" 1416 Content-Length: 1241 1418 1419 1420 1421 http://www.example.com/Coll/ 1422 1423 1424 Loop Demo 1425 1426 urn:uuid:f81d4fae-7dec-11d0-a765-00a0c91e6bf8 1428 1429 1430 HTTP/1.1 200 OK 1431 1432 1433 1434 http://www.example.com/Coll/Foo 1435 1436 1437 Bird Inventory 1438 1439 urn:uuid:f81d4fae-7dec-11d0-a765-00a0c91e6bf9 1441 1442 1443 HTTP/1.1 200 OK 1444 1445 1446 1447 http://www.example.com/Coll/Bar 1448 1449 1450 Loop Demo 1451 1452 urn:uuid:f81d4fae-7dec-11d0-a765-00a0c91e6bf8 1454 1455 1456 HTTP/1.1 208 Already Reported 1457 1458 1459 1461 7.1.2. Example: PROPFIND by Non-Bind-Aware Client 1463 In this example, the client isn't aware of the 208 status code 1464 introduced by this specification. As the "Depth: infinity" PROPFIND 1465 request would cause a loop condition, the whole request is rejected 1466 with a 506 status. 1468 >> Request: 1470 PROPFIND /Coll/ HTTP/1.1 1471 Host: www.example.com 1472 Depth: infinity 1473 Content-Type: application/xml; charset="utf-8" 1474 Content-Length: 125 1476 1477 1478 1479 1481 >> Response: 1483 HTTP/1.1 506 Loop Detected 1485 7.2. 506 Loop Detected 1487 The 506 (Loop Detected) status code indicates that the server 1488 terminated an operation because it encountered an infinite loop while 1489 processing a request with "Depth: infinity". This status indicates 1490 that the entire operation failed. 1492 8. Capability Discovery 1494 8.1. OPTIONS Method 1496 If the server supports bindings, it MUST return the compliance class 1497 name "bind" as a field in the "DAV" response header (see [RFC4918], 1498 Section 10.1) from an OPTIONS request on any resource implemented by 1499 that server. A value of "bind" in the "DAV" header MUST indicate 1500 that the server supports all MUST level requirements and REQUIRED 1501 features specified in this document. 1503 8.2. 'DAV' Request Header 1505 Clients SHOULD signal support for all MUST level requirements and 1506 REQUIRED features by submitting a "DAV" request header containing the 1507 compliance class name "bind". In particular, the client MUST 1508 understand the 208 status code defined in Section 7.1. 1510 9. Relationship to WebDAV Access Control Protocol 1512 BIND and REBIND behave the same as MOVE with respect to the DAV:acl 1513 property (see [RFC3744], Section 7.3). 1515 10. Relationship to Versioning Extensions to WebDAV 1517 Servers that implement Workspaces ([RFC3253], Section 6) and Version 1518 Controlled Collections ([RFC3253], Section 14) already need to 1519 implement BIND-like behavior in order to handle UPDATE and UNCHECKOUT 1520 semantics. 1522 Consider a workspace "/ws1/", containing the version-controlled, 1523 checked-out collections C1 and C2, named "/ws1/CollX" and "/ws1/ 1524 CollY", and a version-controlled resource R, bound to C1 as "/ws1/ 1525 CollX/test": 1527 +-------------------------+ 1528 | Workspace | 1529 | bindings: | 1530 | CollX CollY | 1531 +-------------------------+ 1532 | | 1533 | | 1534 | | 1535 +---------------+ +---------------+ 1536 | Collection C1 | | Collection C2 | 1537 | bindings: | | | 1538 | test | | | 1539 +---------------+ +---------------+ 1540 | 1541 | 1542 | 1543 +------------------+ 1544 | Resource R | 1545 +------------------+ 1547 Moving "/ws1/CollX/test" into "/ws1/CollY", checking in C2, but 1548 undoing the checkout on C1 will undo part of the MOVE request, thus 1549 restoring the binding from C1 to R, but keeping the new binding from 1550 C2 to R: 1552 >> Request: 1554 MOVE /ws1/CollX/test HTTP/1.1 1555 Host: www.example.com 1556 Destination: /ws1/CollY/test 1558 >> Response: 1560 HTTP/1.1 204 No Content 1562 >> Request: 1564 CHECKIN /ws1/CollY/ HTTP/1.1 1565 Host: www.example.com 1567 >> Response: 1569 HTTP/1.1 201 Created 1570 Cache-Control: no-cache 1571 Location: http://repo.example.com/his/17/ver/42 1573 >> Request: 1575 UNCHECKOUT /ws1/CollX/ HTTP/1.1 1576 Host: www.example.com 1578 >> Response: 1580 HTTP/1.1 200 OK 1581 Cache-Control: no-cache 1583 As a result, both C1 and C2 would have a binding to R: 1585 +-------------------------+ 1586 | Workspace | 1587 | bindings: | 1588 | CollX CollY | 1589 +-------------------------+ 1590 | | 1591 | | 1592 | | 1593 +---------------+ +---------------+ 1594 | Collection C1 | | Collection C2 | 1595 | bindings: | | bindings: | 1596 | test | | test | 1597 +---------------+ +---------------+ 1598 | | 1599 | | 1600 | | 1601 +------------------+ 1602 | Resource R | 1603 +------------------+ 1605 The MOVE semantics defined in Section 3.15 of [RFC3253] already 1606 require that "/ws1/CollX/test" and "/ws1/CollY/test" will have the 1607 same version history (as exposed in the DAV:version-history 1608 property). Furthermore, the UNCHECKOUT semantics (which in this case 1609 is similar to UPDATE, see Section 14.11 of [RFC3253]) require: 1611 ...If a new version-controlled member is in a workspace that 1612 already has a version-controlled resource for that version 1613 history, then the new version-controlled member MUST be just a 1614 binding (i.e., another name for) that existing version-controlled 1615 resource... 1617 Thus, "/ws1/CollX/test" and "/ws1/CollY/test" will be bindings to the 1618 same resource R, and have identical DAV:resource-id properties. 1620 11. Security Considerations 1622 This section is provided to make WebDAV implementors aware of the 1623 security implications of this protocol. 1625 All of the security considerations of HTTP/1.1 ([RFC2616], Section 1626 15) and the WebDAV Distributed Authoring Protocol specification 1627 ([RFC4918], Section 20) also apply to this protocol specification. 1628 In addition, bindings introduce several new security concerns and 1629 increase the risk of some existing threats. These issues are 1630 detailed below. 1632 11.1. Privacy Concerns 1634 In a context where cross-server bindings are supported, creating 1635 bindings on a trusted server may make it possible for a hostile agent 1636 to induce users to send private information to a target on a 1637 different server. 1639 11.2. Bind Loops 1641 Although bind loops were already possible in HTTP 1.1, the 1642 introduction of the BIND method creates a new avenue for clients to 1643 create loops accidentally or maliciously. If the binding and its 1644 target are on the same server, the server may be able to detect BIND 1645 requests that would create loops. Servers are required to detect 1646 loops that are caused by bindings to collections during the 1647 processing of any requests with "Depth: infinity". 1649 11.3. Bindings, and Denial of Service 1651 Denial of service attacks were already possible by posting URIs that 1652 were intended for limited use at heavily used Web sites. The 1653 introduction of BIND creates a new avenue for similar denial of 1654 service attacks. If cross-server bindings are supported, clients can 1655 now create bindings at heavily used sites to target locations that 1656 were not designed for heavy usage. 1658 11.4. Private Locations May Be Revealed 1660 If the DAV:parent-set property is maintained on a resource, the 1661 owners of the bindings risk revealing private locations. The 1662 directory structures where bindings are located are available to 1663 anyone who has access to the DAV:parent-set property on the resource. 1664 Moving a binding may reveal its new location to anyone with access to 1665 DAV:parent-set on its resource. 1667 11.5. DAV:parent-set and Denial of Service 1669 If the server maintains the DAV:parent-set property in response to 1670 bindings created in other administrative domains, it is exposed to 1671 hostile attempts to make it devote resources to adding bindings to 1672 the list. 1674 12. Internationalization Considerations 1676 All internationalization considerations mentioned in Section 19 of 1677 [RFC4918] also apply to this document. 1679 13. IANA Considerations 1681 Section 7 defines the HTTP status codes 208 (Already Reported) and 1682 506 (Loop Detected), to be added to the registry at 1683 . 1685 14. Acknowledgements 1687 This document is the collaborative product of the authors and Tyson 1688 Chihaya, Jim Davis, Chuck Fay and Judith Slein. It has benefited 1689 from thoughtful discussion by Jim Amsden, Peter Carlson, Steve 1690 Carter, Ken Coar, Ellis Cohen, Dan Connolly, Bruce Cragun, Cyrus 1691 Daboo, Spencer Dawkins, Mark Day, Werner Donne, Rajiv Dulepet, David 1692 Durand, Lisa Dusseault, Stefan Eissing, Roy Fielding, Yaron Goland, 1693 Joe Hildebrand, Fred Hitt, Alex Hopmann, James Hunt, Marcus Jager, 1694 Chris Kaler, Manoj Kasichainula, Rohit Khare, Brian Korver, Daniel 1695 LaLiberte, Steve Martin, Larry Masinter, Jeff McAffer, Alexey 1696 Melnikov, Surendra Koduru Reddy, Max Rible, Sam Ruby, Bradley 1697 Sergeant, Nick Shelness, John Stracke, John Tigue, John Turner, Kevin 1698 Wiggen, and other members of the concluded WebDAV working group. 1700 15. References 1702 15.1. Normative References 1704 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 1705 Requirement Levels", BCP 14, RFC 2119, March 1997. 1707 [RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., 1708 Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext 1709 Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999. 1711 [RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform 1712 Resource Identifier (URI): Generic Syntax", STD 66, 1713 RFC 3986, January 2005. 1715 [RFC4918] Dusseault, L., Ed., "HTTP Extensions for Web Distributed 1716 Authoring and Versioning (WebDAV)", RFC 4918, June 2007. 1718 [XML] Bray, T., Paoli, J., Sperberg-McQueen, C., Maler, E., and 1719 F. Yergeau, "Extensible Markup Language (XML) 1.0 (Fifth 1720 Edition)", W3C REC-xml-20081126, November 2008, 1721 . 1723 15.2. Informative References 1725 [RFC3253] Clemm, G., Amsden, J., Ellison, T., Kaler, C., and J. 1726 Whitehead, "Versioning Extensions to WebDAV (Web 1727 Distributed Authoring and Versioning)", RFC 3253, 1728 March 2002. 1730 [RFC3744] Clemm, G., Reschke, J., Sedlar, E., and J. Whitehead, "Web 1731 Distributed Authoring and Versioning (WebDAV) Access 1732 Control Protocol", RFC 3744, May 2004. 1734 [RFC4122] Leach, P., Mealling, M., and R. Salz, "A Universally 1735 Unique IDentifier (UUID) URN Namespace", RFC 4122, 1736 July 2005. 1738 Appendix A. Clarification to RFC4918 Usage of the Term 'Lock Root' 1740 [RFC4918], Section 9.10.1 claims: 1742 A LOCK request to an existing resource will create a lock on the 1743 resource identified by the Request-URI, provided the resource is 1744 not already locked with a conflicting lock. The resource 1745 identified in the Request-URI becomes the root of the lock. 1747 This is misleading in that it implies that the "lock root" is the 1748 directly locked resource, not the URI through which the lock was 1749 requested (see 1750 ). As a matter 1751 of fact, other parts of the specification use the term "lock-root" to 1752 talk about that URI (see [RFC4918], Section 6.1, Item 2, and Section 1753 14.12). With that definition, it becomes clear that a lock affects 1754 the resource identified by the Request-URI (plus optionally its 1755 descendants), plus the URI through which the lock was requested, but 1756 not URIs mapped to that resource due to the existence of additional 1757 bindings. 1759 A clearer description would be: 1761 A LOCK request to an existing resource will create a lock on the 1762 resource identified by the Request-URI, provided the resource is 1763 not already locked with a conflicting lock. The Request-URI 1764 becomes the "lock-root" of the lock. 1766 Note that this change makes the description consistent with the 1767 definition of the DAV:lockroot XML element in Section 14.12 of 1768 [RFC4918]. 1770 A.1. Example: Locking and Multiple Bindings 1772 This example shows how the clarification above is relevant when a 1773 locked resource is addressable through multiple URIs. 1775 Consider a root collection "/", containing the two collections C1 and 1776 C2, named "/CollX" and "/CollY", and a child resource R, bound to C1 1777 as "/CollX/test" and bound to C2 as "/CollY/test": 1779 +-------------------------+ 1780 | Root Collection | 1781 | bindings: | 1782 | CollX CollY | 1783 +-------------------------+ 1784 | | 1785 | | 1786 | | 1787 +---------------+ +---------------+ 1788 | Collection C1 | | Collection C2 | 1789 | bindings: | | bindings: | 1790 | test | | test | 1791 +---------------+ +---------------+ 1792 | | 1793 | | 1794 | | 1795 +------------------+ 1796 | Resource R | 1797 +------------------+ 1799 Given a host name of "www.example.com", applying a depth-zero write 1800 lock to "/CollX/test" will lock the resource R, and the lock-root of 1801 this lock will be "http://www.example.com/CollX/test". 1803 Thus the following operations will require that the associated lock 1804 token is submitted with the "If" request header ([RFC4918], Section 1805 10.4): 1807 o a PUT or PROPPATCH request modifying the content or lockable 1808 properties of resource R (as R is locked) -- no matter which URI 1809 is used as request target, 1811 o a MOVE, REBIND, UNBIND or DELETE request causing "/CollX/test" not 1812 being mapped to resource R anymore (be it addressed to "/CollX" or 1813 "/CollX/test"). 1815 The following operations will not require submission of the lock 1816 token: 1818 o a DELETE request addressed to "/CollY" or /CollY/test", as it does 1819 not affect the resource R, nor the lock-root, 1821 o for the same reason, an UNBIND request removing the binding "test" 1822 from collection C2, or the binding "CollY" from the root 1823 collection, 1825 o similarly, a MOVE or REBIND request causing "/CollY/test" not 1826 being mapped to resource R anymore. 1828 Note that despite the lock root being 1829 "http://www.example.com/CollX/test", an UNLOCK request can be 1830 addressed through any URI mapped to resource R, as UNLOCK operates on 1831 the resource identified by the request URI, not that URI (see 1832 [RFC4918], Section 9.11). 1834 Appendix B. Change Log (to be removed by RFC Editor before publication) 1836 B.1. Since draft-ietf-webdav-bind-02 1838 Add and resolve issues "2.3_COPY_SHARED_BINDINGS" and 1839 "2.3_MULTIPLE_COPY". Add issue "5.1_LOOP_STATUS" and proposed 1840 resolution, but keep it open. Add issues "ED_references" and 1841 "4_507_status". Started work on index. Rename document to "Binding 1842 Extensions to Web Distributed Authoring and Versioning (WebDAV)". 1843 Rename "References" to "Normative References". Close issue 1844 "ED_references". Close issue "4_507_status". 1846 B.2. Since draft-ietf-webdav-bind-03 1848 Add and close issues "9.2_redirect_loops", "ED_authors" and 1849 "ED_updates". Add section about capability discovery (DAV header). 1850 Close issues "5.1_LOOP_STATUS". Add and resolve new issue 1851 "5.1_506_STATUS_STREAMING". Update XML spec reference. Add issue 1852 "locking" and resolve as invalid. 1854 B.3. Since draft-ietf-webdav-bind-04 1856 Add and close issues "6_precondition_binding_allowed" and 1857 "6_lock_behaviour". Add mailing list and issues list pointers to 1858 front. 1860 B.4. Since draft-ietf-webdav-bind-05 1862 Editorial fixes. Add and resolve issues "1.3_error_negotiation", 1863 "2.5_language" and "7.1.1_add_resource_id". Add historical issue 1864 "4_LOCK_BEHAVIOR" and it's resolution for better tracking. 1866 B.5. Since draft-ietf-webdav-bind-06 1868 Rewrite Editorial Note. Open and resolve issues "2.6_identical", 1869 "specify_safeness_and_idempotence" and "ED_rfc2026_ref". 1871 B.6. Since draft-ietf-webdav-bind-07 1873 Add more index items (no change tracking). Add and resolve issues 1874 "2.3_copy_to_same", "bind_properties", "bind_vs_ACL", 1875 "6_rebind_intro" and "rfc2396bis" (actually an action item). Fix XML 1876 DTD fragment in section 3.3. Make spelling of "Request-URI" 1877 consistent. 1879 B.7. Since draft-ietf-webdav-bind-08 1881 Resolved editorial issues raised by Jim Whitehead in . 1883 Add and resolve issues "atomicity", "2_allow_destroy", 1884 "2.1_separate_loop_discussion", "2.1.1_bind_loops_vs_locks", 1885 "2.3_copy_depth_infinity", "2.3_copy_example", "2.3_copy_vs_loops", 1886 "2.6_resource-id_vs_versions", "3.2_example" and 1887 "6_rebind_premissions". Add issue "2.6_when_do_ids_change". Re-open 1888 and resolve "6_rebind_intro". 1890 B.8. Since draft-ietf-webdav-bind-09 1892 Add and resolve issue "6.1_rebind_vs_locks", adding proposed example 1893 text. Add action item "3.1_uuids". Close issue 1894 "2.6_when_do_ids_change". Add and resolve issues 1895 "2.6_bindings_vs_properties" and "uri_draft_ref". 1897 B.9. Since draft-ietf-webdav-bind-10 1899 Resolve action item "3.1_uuids". Add and resolve issue 1900 "2.7_unlock_vs_bindings". Revisit issue 1901 "2.6_bindings_vs_properties", and remove the part of the sentence 1902 that speaks about live properties. Update "rfc2396bis" references to 1903 "RFC3986". Add issue "9_ns_op_and_acl" and add potential resolution. 1904 Align artwork where applicable (new xml2rfc1.29rc2 feature). 1906 B.10. Since draft-ietf-webdav-bind-11 1908 Updated [draft-mealling-uuid-urn] to [RFC4122]. Add statement about 1909 live properties in Section 2.6. 1911 B.11. Since draft-ietf-webdav-bind-12 1913 Updated Author's address. Uppercase "Section" when referring to 1914 other documents. 1916 Updating from RFC2518 to RFC2518bis: 1918 o Remove own explanation of DTD syntax. 1920 o Remove own definition of precondition/postcondition. 1922 o Remove reference to broken RFC2518 language about DELETE and 1923 UNLOCK. 1925 o Remove own definition of DAV: request header. 1927 o Updated "Rationale for Distinguishing Bindings from URI Mappings" 1928 to reflect the changes in [draft-ietf-webdav-rfc2518bis], making 1929 proposals for more changes so that the issue can be closed (see 1930 also 1931 and ). 1934 B.12. Since draft-ietf-webdav-bind-13 1936 Update [draft-ietf-webdav-rfc2518-bis] to draft 14. Update one 1937 incorrect section reference. Remove Section "Rationale for 1938 Distinguishing Bindings from URI Mappings" as 1939 [draft-ietf-webdav-rfc2518-bis] now uses the proper definition of 1940 collection state. Examples use application/xml instead of text/xml 1941 MIME type. 1943 Fix IANA section (there are no IANA considerations). 1945 B.13. Since draft-ietf-webdav-bind-14 1947 Update [draft-ietf-webdav-rfc2518-bis] to draft 15. Update [XML] to 1948 4th edition. 1950 Markup ASCII art for box recognition (doesn't affect ASCII version). 1952 Identify Julian Reschke as Editor. 1954 B.14. Since draft-ietf-webdav-bind-15 1956 Fix typo in RFC2119 keywords section (sorry!). 1958 Update [draft-ietf-webdav-rfc2518-bis] to draft 17. 1960 Add and resolve issue "rfc2518bis-lock-root". 1962 B.15. Since draft-ietf-webdav-bind-16 1964 Add and resolve issue "iana-vs-http-status". 1966 B.16. Since draft-ietf-webdav-bind-17 1968 Update rfc2518bis reference to draft 18 (note that the bug reported 1969 in 1970 is still present). 1972 B.17. Since draft-ietf-webdav-bind-18 1974 Update: draft-ietf-webdav-rfc2518bis replaced by RFC4918. 1976 B.18. Since draft-ietf-webdav-bind-19 1978 Add and resolve issues "2.1.1-bind-loops", "2.1.1-cycles", "2.5-move- 1979 creating-cycles", "3.1-clarify-resource-id" and "4-precondition- 1980 language". 1982 B.19. Since draft-ietf-webdav-bind-20 1984 Use "urn:uuid:" instead of "opaquelocktoken:" scheme in examples. 1985 Replace RFC2518bis issue link by pointer to RFC Errata Page. 1987 Add issues "relation-to-deltav" and "status-codes". 1989 B.20. Since draft-ietf-webdav-bind-21 1991 Resolve issues "relation-to-deltav" and "status-codes". 1993 Add correct content length values to examples (no change bars). 1995 B.21. Since draft-ietf-webdav-bind-22 1997 Set "Intended Status" to "Experimental". 1999 Update XML reference to "Extensible Markup Language (XML) 1.0 (Fifth 2000 Edition)". 2002 B.22. Since draft-ietf-webdav-bind-23 2004 Remove surplus white space from one example. 2006 Fix typo: "DAV:binding-set" -> "DAV:parent-set". 2008 Add and resolve issues "clarify-alternate-uri", "def-integrity", "ex- 2009 copy-multiple-update", "ex-copy-graph", and "ex-live-property". 2011 B.23. Since draft-ietf-webdav-bind-24 2013 Add and resolve issues "clarify-clarify", "sec-cons-references", 2014 "should-not-update-4918", "should-update-2616", and "webdav-wg-gone". 2016 B.24. Since draft-ietf-webdav-bind-25 2018 Add and resolve issue "locking-example". 2020 Appendix C. Resolved issues (to be removed by RFC Editor before 2021 publication) 2023 Issues that were either rejected or resolved in this version of this 2024 document. 2026 C.1. edit 2028 Type: edit 2030 julian.reschke@greenbytes.de (2004-05-30): Umbrella issue for 2031 editorial fixes/enhancements. 2033 C.2. locking-example 2035 In Section A: 2037 Type: edit 2039 julian.reschke@greenbytes.de (2009-09-05): Based on IESG feedback: 2040 add an example showing a case where the text below becomes relevant. 2042 Resolution: Example added. 2044 Index 2046 2 2047 208 Already Reported (status code) 32, 40 2049 5 2050 506 Loop Detected (status code) 35, 40 2052 B 2053 BIND method 22 2054 Marshalling 23 2055 Postconditions 24 2056 Preconditions 23 2057 Binding 7 2058 Binding Integrity 7-8, 22 2060 C 2061 Collection 7 2062 Condition Names 2063 DAV:bind-into-collection (pre) 23 2064 DAV:bind-source-exists (pre) 23 2065 DAV:binding-allowed (pre) 24 2066 DAV:binding-deleted (post) 26, 29 2067 DAV:can-overwrite (pre) 24, 28 2068 DAV:cross-server-binding (pre) 24, 28 2069 DAV:cycle-allowed (pre) 24, 28 2070 DAV:lock-deleted (post) 26, 29 2071 DAV:locked-overwrite-allowed (pre) 24 2072 DAV:locked-source-collection-update-allowed (pre) 29 2073 DAV:locked-update-allowed (pre) 24, 26, 28 2074 DAV:name-allowed (pre) 24, 28 2075 DAV:new-binding (post) 24, 29 2076 DAV:protected-source-url-deletion-allowed (pre) 29 2077 DAV:protected-url-deletion-allowed (pre) 26 2078 DAV:protected-url-modification-allowed (pre) 28 2079 DAV:rebind-from-collection (pre) 28 2080 DAV:rebind-source-exists (pre) 28 2081 DAV:unbind-from-collection (pre) 26 2082 DAV:unbind-source-exists (pre) 26 2084 D 2085 DAV header 2086 compliance class 'bind' 35 2087 DAV:bind-into-collection precondition 23 2088 DAV:bind-source-exists precondition 23 2089 DAV:binding-allowed precondition 24 2090 DAV:binding-deleted postcondition 26, 29 2091 DAV:can-overwrite precondition 24, 28 2092 DAV:cross-server-binding precondition 24, 28 2093 DAV:cycle-allowed precondition 24, 28 2094 DAV:lock-deleted postcondition 26, 29 2095 DAV:locked-overwrite-allowed precondition 24 2096 DAV:locked-source-collection-update-allowed precondition 29 2097 DAV:locked-update-allowed precondition 24, 26, 28 2098 DAV:name-allowed precondition 24, 28 2099 DAV:new-binding postcondition 24, 29 2100 DAV:parent-set property 21 2101 DAV:protected-source-url-deletion-allowed precondition 29 2102 DAV:protected-url-deletion-allowed precondition 26 2103 DAV:protected-url-modification-allowed precondition 28 2104 DAV:rebind-from-collection precondition 28 2105 DAV:rebind-source-exists precondition 28 2106 DAV:resource-id property 20 2107 DAV:unbind-from-collection precondition 26 2108 DAV:unbind-source-exists precondition 26 2110 I 2111 Internal Member URI 7 2113 M 2114 Methods 2115 BIND 22 2116 REBIND 27 2117 UNBIND 25 2119 P 2120 Path Segment 6 2121 Properties 2122 DAV:parent-set 21 2123 DAV:resource-id 20 2125 R 2126 REBIND method 27 2127 Marshalling 27 2128 Postconditions 29 2129 Preconditions 28 2131 S 2132 Status Codes 2133 208 Already Reported 32, 40 2134 506 Loop Detected 35, 40 2136 U 2137 UNBIND method 25 2138 Marshalling 25 2139 Postconditions 26 2140 Preconditions 26 2141 URI Mapping 6 2143 Authors' Addresses 2145 Geoffrey Clemm 2146 IBM 2147 20 Maguire Road 2148 Lexington, MA 02421 2150 Email: geoffrey.clemm@us.ibm.com 2152 Jason Crawford 2153 IBM Research 2154 P.O. Box 704 2155 Yorktown Heights, NY 10598 2157 Email: ccjason@us.ibm.com 2159 Julian F. Reschke (editor) 2160 greenbytes GmbH 2161 Hafenweg 16 2162 Muenster, NW 48155 2163 Germany 2165 Email: julian.reschke@greenbytes.de 2167 Jim Whitehead 2168 UC Santa Cruz, Dept. of Computer Science 2169 1156 High Street 2170 Santa Cruz, CA 95064 2172 Email: ejw@cse.ucsc.edu