XEP-0058: Multi-User Text Editing

Abstract:This document defines how several people may simultaneously edit text.
Author:Alexey Shchepin
Copyright:© 1999 - 2014 XMPP Standards Foundation. SEE LEGAL NOTICES.
Status:Deferred
Type:Standards Track
Version:0.1
Last Updated:2002-11-12

WARNING: Consideration of this document has been Deferred by the XMPP Standards Foundation. Implementation of the protocol described herein is not recommended.


Table of Contents


1. Introduction
2. Protocol description
3. Formal Definitions

Appendices
    A: Document Information
    B: Author Information
    C: Legal Notices
    D: Relation to XMPP
    E: Discussion Venue
    F: Requirements Conformance
    G: Notes
    H: Revision History


1. Introduction

This document defines an XMPP protocol extension for editing one text document by several people. This can be useful when several people write different parts of one single document, or one person edits the text and other people can see the changes. The advantage of using this protocol in compared to using a version control systems is that all changes are distributed between editors in real-time.

2. Protocol description

To start editing a file, the user must subscribe to it on special "server" The server stores text files. A User first can ask for list of these documents.

Example 1. User asks the server list of editable texts

<iq type='get' to='server' id='mute1'>
  <list xmlns='http://jabber.org/protocol/mute#server'/>
</iq>

After that the server returns a list of the documents. For each list item an ID and description is given.

Example 2. Ancestor returns list of editable texts

<iq type='result' to='editor1' id='mute1'>
  <list xmlns='http://jabber.org/protocol/mute#server'>
    <item id='id1' desc='Useful text'/>
    <item id='id2' desc='Useless text'/>
  </list>
</iq>

Then the user can send a subscribe request to the server by sending the documents ID. Attribute type can be rdwr for full access or rdonly for read-only access.

Example 3. User sends subscribe request

<iq type='set' to='server' id='mute2'>
  <subscribe xmlns='http://jabber.org/protocol/mute#server'>
    <item id='id1' type='rdwr'/>
  </subscribe>
</iq>

Example 4. Positive response from server on subscribe request

<iq type='result' to='editor1' id='mute2'/>

Example 5. Negative response from server on subscribe request

<iq type='error' to='editor1' id='mute2'>
  <subscribe xmlns='http://jabber.org/protocol/mute#server'>
    <item id='id1' type='rdwr'/>
  </subscribe>
  <error code="405">Not Allowed</error>
</iq>

After successful subscription, the server sends the full contents of the document to the new editor.

Example 6. Server sends text to editor

<iq type='set' to='editor1' id='mute3'>
  <text xmlns='http://jabber.org/protocol/mute#editor' id='id1'>
...
8. Admin Use Cases
   8.1. Banning a User
   8.2. Modifying the Ban List
   8.3. Granting Membership
   8.4. Revoking Mambership
   8.5. Modifying the Member List
   8.6. Granting Moderator Privileges
   8.7. Revoking Moderator Privileges
   8.8. Modifying the Moderator List  
...
  </text>
</iq>

Example 7. Positive response from editor

<iq type='result' to='server' id='mute3'/>

If an editor wants to commit the changes he made, then he sends a patch file to this text in GNU diff(1) unified format without first two lines (they specify file names and modification dates, that is not needed).

Example 8. Editor sends patch to server

<iq type='set' to='server' id='mute4'>
  <patch xmlns='http://jabber.org/protocol/mute#server' id='id1'>
@@ -2,7 +2,7 @@
    8.1. Banning a User
    8.2. Modifying the Ban List
    8.3. Granting Membership
-   8.4. Revoking Mambership
+   8.4. Revoking Membership
    8.5. Modifying the Member List
    8.6. Granting Moderator Privileges
    8.7. Revoking Moderator Privileges
  </patch>
</iq>

Example 9. Server accepts patch

<iq type='result' to='editor1' id='mute4'/>

Example 10. Server not accepts patch

<iq type='error' to='editor1' id='mute4'>
  <patch xmlns='http://jabber.org/protocol/mute#server' id='id1'>
@@ -2,7 +2,7 @@
    8.1. Banning a User
    8.2. Modifying the Ban List
    8.3. Granting Membership
-   8.4. Revoking Mambership
+   8.4. Revoking Membership
    8.5. Modifying the Member List
    8.6. Granting Moderator Privileges
    8.7. Revoking Moderator Privileges
  </patch>
  <error code="405">Not Allowed</error>
</iq>

If server accepts the patch, then it resends it to all subscribed text editors and readers.

Example 11. Server resend accepted patch to all editors and readers of this text

<iq type='set' to='editor1' id='mute5'>
  <patch xmlns='http://jabber.org/protocol/mute#editor' id='id1'>
@@ -2,7 +2,7 @@
    8.1. Banning a User
    8.2. Modifying the Ban List
    8.3. Granting Membership
-   8.4. Revoking Mambership
+   8.4. Revoking Membership
    8.5. Modifying the Member List
    8.6. Granting Moderator Privileges
    8.7. Revoking Moderator Privileges
  </patch>
</iq>

Example 12. Positive response from editors and readers

<iq type='result' to='server' id='mute5'/>

If server receives an error IQ reply from one of the editors/readers on any of above requests, then it must remove him from subscribers list and may send a message to him about this.

3. Formal Definitions

Example 13. DTD for http://jabber.org/protocol/mute#server

<?xml version="1.0" encoding="UTF-8" ?>

<!ELEMENT list ((item)*)>
<!ELEMENT subscribe (item)>

<!ELEMENT item EMPTY>
<!ATTLIST item
          id CDATA #REQUIRED
          desc CDATA #IMPLIED
          type ( rdwr | rdonly ) #IMPLIED >

<!ELEMENT patch (#PCDATA)>

Example 14. DTD for http://jabber.org/protocol/mute#editor

<?xml version="1.0" encoding="UTF-8" ?>

<!ELEMENT patch (#PCDATA)>
<!ELEMENT text (#PCDATA)>

Appendices


Appendix A: Document Information

Series: XEP
Number: 0058
Publisher: XMPP Standards Foundation
Status: Deferred
Type: Standards Track
Version: 0.1
Last Updated: 2002-11-12
Approving Body: XMPP Council
Dependencies: None
Supersedes: None
Superseded By: None
Short Name:
Source Control: HTML
This document in other formats: XML  PDF


Appendix B: Author Information

Alexey Shchepin

Email: alexey@sevcom.net
JabberID: aleksey@jabber.ru


Appendix C: Legal Notices

Copyright

This XMPP Extension Protocol is copyright © 1999 - 2014 by the XMPP Standards Foundation (XSF).

Permissions

Permission is hereby granted, free of charge, to any person obtaining a copy of this specification (the "Specification"), to make use of the Specification without restriction, including without limitation the rights to implement the Specification in a software program, deploy the Specification in a network service, and copy, modify, merge, publish, translate, distribute, sublicense, or sell copies of the Specification, and to permit persons to whom the Specification is furnished to do so, subject to the condition that the foregoing copyright notice and this permission notice shall be included in all copies or substantial portions of the Specification. Unless separate permission is granted, modified works that are redistributed shall not contain misleading information regarding the authors, title, number, or publisher of the Specification, and shall not claim endorsement of the modified works by the authors, any organization or project to which the authors belong, or the XMPP Standards Foundation.

Disclaimer of Warranty

## NOTE WELL: This Specification is provided on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, express or implied, including, without limitation, any warranties or conditions of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A PARTICULAR PURPOSE. ##

Limitation of Liability

In no event and under no legal theory, whether in tort (including negligence), contract, or otherwise, unless required by applicable law (such as deliberate and grossly negligent acts) or agreed to in writing, shall the XMPP Standards Foundation or any author of this Specification be liable for damages, including any direct, indirect, special, incidental, or consequential damages of any character arising from, out of, or in connection with the Specification or the implementation, deployment, or other use of the Specification (including but not limited to damages for loss of goodwill, work stoppage, computer failure or malfunction, or any and all other commercial damages or losses), even if the XMPP Standards Foundation or such author has been advised of the possibility of such damages.

IPR Conformance

This XMPP Extension Protocol has been contributed in full conformance with the XSF's Intellectual Property Rights Policy (a copy of which can be found at <http://xmpp.org/about-xmpp/xsf/xsf-ipr-policy/> or obtained by writing to XMPP Standards Foundation, 1899 Wynkoop Street, Suite 600, Denver, CO 80202 USA).

Appendix D: Relation to XMPP

The Extensible Messaging and Presence Protocol (XMPP) is defined in the XMPP Core (RFC 6120) and XMPP IM (RFC 6121) specifications contributed by the XMPP Standards Foundation to the Internet Standards Process, which is managed by the Internet Engineering Task Force in accordance with RFC 2026. Any protocol defined in this document has been developed outside the Internet Standards Process and is to be understood as an extension to XMPP rather than as an evolution, development, or modification of XMPP itself.


Appendix E: Discussion Venue

The primary venue for discussion of XMPP Extension Protocols is the <standards@xmpp.org> discussion list.

Discussion on other xmpp.org discussion lists might also be appropriate; see <http://xmpp.org/about/discuss.shtml> for a complete list.

Errata can be sent to <editor@xmpp.org>.


Appendix F: Requirements Conformance

The following requirements keywords as used in this document are to be interpreted as described in RFC 2119: "MUST", "SHALL", "REQUIRED"; "MUST NOT", "SHALL NOT"; "SHOULD", "RECOMMENDED"; "SHOULD NOT", "NOT RECOMMENDED"; "MAY", "OPTIONAL".


Appendix G: Notes


Appendix H: Revision History

Note: Older versions of this specification might be available at http://xmpp.org/extensions/attic/

Version 0.1 (2002-11-12)

Initial version. (as)

END