XEP-0194: User Chatting

This document defines an XMPP protocol extension for communicating information about the chatrooms a user visits.

WARNING: This Standards-Track document is Experimental. Publication as an XMPP Extension Protocol does not imply approval of this proposal by the XMPP Standards Foundation. Implementation of the protocol described herein is encouraged in exploratory implementations, but production systems should not deploy implementations of this protocol until it advances to a status of Draft.

Document Information

Author Information

Peter Saint-Andre

JabberID: stpeter@jabber.org
URI: https://stpeter.im/

Legal Notices

Copyright

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.

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## 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. In no event shall the XMPP Standards Foundation or the authors of this Specification be liable for any claim, damages, or other liability, whether in an action of contract, tort, or otherwise, arising from, out of, or in connection with the Specification or the implementation, deployment, or other use of the Specification. ##

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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 out of the use or inability to use 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 may be found at <http://www.xmpp.org/extensions/ipr-policy.shtml> or obtained by writing to XSF, P.O. Box 1641, Denver, CO 80201 USA).

Discussion Venue

Relation to XMPP

The Extensible Messaging and Presence Protocol (XMPP) is defined in the XMPP Core (RFC 3920) and XMPP IM (RFC 3921) 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.

Conformance Terms

The following 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".

1. Introduction
2. Protocol
    2.1. Container Element and Child Elements
    2.2. Transport Mechanism
3. Security Considerations
4. IANA Considerations
5. XMPP Registrar Considerations
    5.1. Protocol Namespaces
6. XML Schema
Notes
Revision History

1. Introduction

Publish-Subscribe [1] and Personal Eventing via Pubsub [2] can be used to publish a wide variety of "extended presence" information about users. This document specifies an extended presence payload format that communicates information about the chatrooms a user visits. This information may be of interest to a user's contacts and can also be used in social networking applications.

2. Protocol

2.1 Container Element and Child Elements

Information about chatrooms is provided by the user (or automated integration with Jabber, IRC, or other systems) and is propagated on the network by the user's client. The information container for chatting data is a <room/> element that is qualified by the 'http://www.xmpp.org/extensions/xep-0194.html#ns' namespace (see Protocol Namespaces regarding issuance of one or more permanent namespaces). The chatting information itself is provided as the XML character data of the following children of the <room/> element:

Table 1: Child Elements

Element	Description	Example	Datatype	Inclusion
name	The name of the chatroom	Jabber Development	xs:string	OPTIONAL
topic	The current topic of discussion in the room	whiteboard brainstorming session	xs:string	OPTIONAL
uri	A URI for the room (this SHOULD be an XMPP URI or IRI in accordance with RFC 5122 [3] but MAY use some other URI scheme, such as the irc: scheme)	xmpp:jdev@conference.jabber.org	xs:anyURI	REQUIRED

NOTE: The datatypes specified above are defined in XML Schema Part 2 [4].

2.2 Transport Mechanism

When a user joins a room, its client may publish that fact to PEP node whose NodeID is "http://www.xmpp.org/extensions/xep-0194.html#ns" (see Protocol Namespaces regarding issuance of one or more permanent namespaces) or to a generic pubsub node. Because chatroom information is not pure presence information and can change independently of the user's availability, it SHOULD NOT be provided as an extension to the <presence/> stanza type.

Example 1. User Publishes Chatting Information

<iq type='set' from='stpeter@jabber.org/work' id='chatting1'>
  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
    <publish node='http://www.xmpp.org/extensions/xep-0194.html#ns'>
      <item id='1b395148292c0b0ab3a83bb2c22909bf83d2a80b'>
        <room xmlns='http://www.xmpp.org/extensions/xep-0194.html#ns'>
          <name>Jabber Development</name>
          <uri>xmpp:jdev@conference.jabber.org</uri>
        </room>
      </item>
    </publish>
  </pubsub>
</iq>

The chatting information is then delivered to all subscribers:

Example 2. Chatting Information is Delivered to All Subscribers

<message from='stpeter@jabber.org' to='maineboy@jabber.org'>
  <event xmlns='http://jabber.org/protocol/pubsub#event'>
    <items node='http://www.xmpp.org/extensions/xep-0194.html#ns'>
      <item id='1b395148292c0b0ab3a83bb2c22909bf83d2a80b'>
        <room xmlns='http://www.xmpp.org/extensions/xep-0194.html#ns'>
          <name>Jabber Development</name>
          <uri>xmpp:jdev@conference.jabber.org</uri>
        </room>
      </item>
    </items>
  </event>
</message>

[ ... ]

When the user exits the room, the user's client SHOULD send an empty <room/> element with the same ItemID:

Example 3. User Publishes Exit Information

<iq type='set' from='stpeter@jabber.org/work' id='chatting2'>
  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
    <publish node='http://www.xmpp.org/extensions/xep-0194.html#ns'>
      <item id='1b395148292c0b0ab3a83bb2c22909bf83d2a80b'>
        <room xmlns='http://www.xmpp.org/extensions/xep-0194.html#ns'/>
      </item>
    </publish>
  </pubsub>
</iq>

Example 4. Empty Room Information is Delivered to All Subscribers

<message from='stpeter@jabber.org' to='maineboy@jabber.org'>
  <event xmlns='http://jabber.org/protocol/pubsub#event'>
    <items node='http://www.xmpp.org/extensions/xep-0194.html#ns'>
      <item id='1b395148292c0b0ab3a83bb2c22909bf83d2a80b'>
        <room xmlns='http://www.xmpp.org/extensions/xep-0194.html#ns'/>
      </item>
    </items>
  </event>
</message>

[ ... ]

3. Security Considerations

The chat rooms that a user visits may be sensitive. A client MUST provide a way for a user to configure which rooms or types of rooms will not be published (e.g., via user preferences).

4. IANA Considerations

5. XMPP Registrar Considerations

5.1 Protocol Namespaces

Until this specification advances to a status of Draft, its associated namespace shall be "http://www.xmpp.org/extensions/xep-0194.html#ns"; upon advancement of this specification, the XMPP Registrar [6] shall issue a permanent namespace in accordance with the process defined in Section 4 of XMPP Registrar Function [7].

6. XML Schema

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

<xs:schema
    xmlns:xs='http://www.w3.org/2001/XMLSchema'
    targetNamespace='http://www.xmpp.org/extensions/xep-0194.html#ns'
    xmlns='http://www.xmpp.org/extensions/xep-0194.html#ns'
    elementFormDefault='qualified'>

  <xs:element name='room'>
    <xs:complexType>
      <xs:sequence minOccurs='0'>
        <xs:element name='name' type='xs:string' minOccurs='0'/>
        <xs:element name='topic' type='xs:string' minOccurs='0'/>
        <xs:element name='uri' type='xs:anyURI'/>
      </xs:sequence>
    </xs:complexType>
  </xs:element>

</xs:schema>

Notes

1. XEP-0060: Publish-Subscribe <http://www.xmpp.org/extensions/xep-0060.html>.

2. XEP-0163: Personal Eventing via Pubsub <http://www.xmpp.org/extensions/xep-0163.html>.

3. RFC 5122: Internationalized Resource Identifiers (IRIs) and Uniform Resource Identifiers (URIs) for the Extensible Messaging and Presence Protocol (XMPP) <http://tools.ietf.org/html/rfc5122>.

4. XML Schema Part 2: Datatypes <http://www.w3.org/TR/xmlschema-2/>.

5. The Internet Assigned Numbers Authority (IANA) is the central coordinator for the assignment of unique parameter values for Internet protocols, such as port numbers and URI schemes. For further information, see <http://www.iana.org/>.

6. The XMPP Registrar maintains a list of reserved protocol namespaces as well as registries of parameters used in the context of XMPP extension protocols approved by the XMPP Standards Foundation. For further information, see <http://www.xmpp.org/registrar/>.

7. XEP-0053: XMPP Registrar Function <http://www.xmpp.org/extensions/xep-0053.html>.