JEP-0147: XMPP IRI Query Components

This JEP defines a registry of query components to be used in the context of XMPP IRIs and also specifies an initial submission of values to that registry.


WARNING: This Standards-Track JEP is Experimental. Publication as a Jabber Enhancement Proposal does not imply approval of this proposal by the Jabber Software 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.


JEP Information

Status: Experimental
Type: Standards Track
Number: 0147
Version: 0.4
Last Updated: 2005-06-06
JIG: Standards JIG
Approving Body: Jabber Council
Dependencies: XMPP Core, draft-saintandre-xmpp-iri-00, JEP-0053
Supersedes: None
Superseded By: None
Short Name: N/A

Author Information

Peter Saint-Andre

Email: stpeter@jabber.org
JID: stpeter@jabber.org

Legal Notice

This Jabber Enhancement Proposal is copyright 1999 - 2005 by the Jabber Software Foundation (JSF) and is in full conformance with the JSF's Intellectual Property Rights Policy <http://www.jabber.org/jsf/ipr-policy.shtml>. This material may be distributed only subject to the terms and conditions set forth in the Open Publication License, v1.0 or later (the latest version is presently available at <http://www.opencontent.org/openpub/>).

Discussion Venue

The preferred venue for discussion of this document is the Standards-JIG discussion list: <http://mail.jabber.org/mailman/listinfo/standards-jig>.

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 Jabber Software 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 JEP 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 keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119.


Table of Contents

1. Introduction
2. Terminology
3. Query Actions
3.1. Message Action
3.2. Roster-Related Actions
3.3. Subscription-Related Actions
3.4. Presence Probe Action
3.5. Groupchat-Related Actions
3.6. Registration-Related Actions
3.7. Pubsub-Related Actions
3.8. Disco-Related Actions
4. Internationalization Considerations
5. Security Considerations
6. IANA Considerations
7. Jabber Registrar Considerations
7.1. XMPP IRI Querytype Registry
7.1.1. Process
7.1.2. Initial Registration
Notes
Revision History


1. Introduction

XMPP IRI [1] defines an Internationalized Resource Identifier (IRI) scheme [2] for interaction with XMPP entities (see XMPP Core [3]) by non-native applications, but intentionally leaves the potential values of the query component open-ended. In particular, that document does not provide a list of common "actions" for queries (e.g., send message or join chatroom), nor does it specify recommended "key-value" pairs to be used in the context of such actions. This JEP calls for a registry of such actions and key-value pairs, to be maintained by the Jabber Registrar [4].

Note: The format for XMPP IRIs, including the format of the query component, is fully specified and formally defined in draft-saintandre-xmpp-iri-00; this document does not modify the xmpp: IRI scheme in any way and assumes that the reader is familiar with all aspects of that specification.

2. Terminology

This document inherits terminology from RFC 3986 [5], RFC 3987 [6], and draft-saintandre-xmpp-iri-00.

3. Query Actions

The range of actions that might be triggered by interaction with an XMPP entity by means of an XMPP IRI is potentially as wide as the range of extensions to XMPP. This JEP does not seek to exhaustively defined all such potential actions. However, the following actions might be of general interest, and therefore are described below:

  1. Sending a message.
  2. Adding or removing a roster item.
  3. Subscribing to an entity's presence information.
  4. Probing for current presence information.
  5. Joining a groupchat room (see Multi-User Chat [7]).
  6. Registering with another entity via In-Band Registration [8].
  7. Subscribing to or unsubscribing from a Publish-Subscribe [9] node.
  8. Determining Service Discovery [10] information about an entity.

For each such action, this JEP specifies a recommended "querytype" (this can be thought of as an action name; see draft-saintandre-xmpp-iri-00 for syntax and semantics) as well as a list of keys to be used in key-value pairs if appropriate.

3.1 Message Action

It may desirable for an XMPP IRI to trigger a specialized interface for sending an XMPP message stanza (as opposed to completing some other action). The RECOMMENDED querytype for this action is "message". If no key-value pair is provided, interacting with an XMPP IRI that contains a querytype of "message" SHOULD trigger an interface that enables the user to input the text of an XMPP message and other relevant parameters (e.g., a message subject or XHTML-IM [11] markup).

Example 1. Basic Message Action

xmpp:romeo@montague.net?message
    

A query component whose querytype is "message" MAY specify various key-value pairs. The following three keys are associated with the child elements of the <message/> stanza specified in the XML schema for the 'jabber:client' namespace as defined in XMPP IM [12]:

  1. subject
  2. body
  3. thread

In addition, the following three keys are associated with the attributes of the <message/> stanza specified in the XML schema for the 'jabber:client' namespace (the 'to' attribute is unnecessary, since it is provided by the XMPP address included in the IRI):

  1. from
  2. id
  3. type

Other keys MAY be registered with the Jabber Registrar but are not specified herein.

Example 2. Message Action with Keys: IRI

xmpp:romeo@montague.net?message;subject=Test%20Message;body=Here%27s%20a%20test%20message
    

Example 3. Message Action with Keys: Resulting Stanza

<message to='romeo@montage.net'>
  <subject>Test Message</subject>
  <body>Here&apos;s a test message.</body>
</message>
    

3.2 Roster-Related Actions

The 'jabber:iq:roster' namespace provides a mechanism for managing an XMPP roster (also called a "contact list"). This namespace is defined in RFC 3921. The registered querytype for adding items to the roster or editing items in the roster is "roster" (effectively there is no difference between adding and editing). An XMPP IRI containing a "roster" querytype MAY also include at most one "name" key whose value maps to the 'name' attribute of the <item/> element within the 'jabber:iq:roster' namespace, and MAY contain one "group" key whose value maps to the character data of the <group/> child element of <item/>.

Example 4. Roster Action: IRI

xmpp:romeo@montague.net?roster
    

Example 5. Roster Action: Resulting Stanza

<iq type='set'>
  <query xmlns='jabber:iq:roster'>
    <item jid='romeo@montage.net'/>
  </query>
</iq>
    

Example 6. Roster Action With Name: IRI

xmpp:romeo@montague.net?roster;name=Romeo%20Montague
    

Example 7. Roster Action With Name: Resulting Stanza

<iq type='set'>
  <query xmlns='jabber:iq:roster'>
    <item jid='romeo@montage.net' name='Romeo Montague'/>
  </query>
</iq>
    

Example 8. Roster Action With Name and Group: IRI

xmpp:romeo@montague.net?roster;name=Romeo%20Montague;group=Friends
    

Example 9. Roster Action With Name and Group: Resulting Stanza

<iq type='set'>
  <query xmlns='jabber:iq:roster'>
    <item jid='romeo@montage.net' name='Romeo Montague'>
      <group>Friends</group>
    </item>
  </query>
</iq>
    

Note: Methods for including more than one group are yet to be determined.

3.3 Subscription-Related Actions

Closely coupled with roster management is presence subscription management. In XMPP, subscription management is handled via special values of the <presence/> stanza, as described in RFC 3921. When an entity subscribes to another entity's presence by means of an XMPP IRI, the invoked XMPP application SHOULD first send a roster add stanza as shown below (this is consistent with the recommendations in RFC 3921.

Example 10. Subscribe Action: IRI

xmpp:romeo@montague.net?subscribe
    

Example 11. Subscribe Action: Resulting Stanzas

<iq type='set'>
  <query xmlns='jabber:iq:roster'>
    <item jid='romeo@montage.net'/>
  </query>
</iq>

<presence to='romeo@montague.net' type='subscribe'/>
    

3.4 Presence Probe Action

Once an entity is subscribed to the presence of a contact, it is allowed to probe for the contact's current presence if necessary. Although normally this is done by the server on the user's behalf, the client may initiate a probe as well. The action and resulting protocol are shown below.

Example 12. Probe Action: IRI

xmpp:romeo@montague.net?probe
    

Example 13. Probe Action: Resulting Stanza

<presence to='romeo@montague.net' type='probe'/>
    

3.5 Groupchat-Related Actions

The Jabber network has long included groupchat rooms (similar to IRC channels); this functionality is defined fully in JEP-0045: Multi-User Chat. Two querytype values are registered to enable interaction with groupchat rooms: "join" and "invite".

Example 14. Join Action: IRI

xmpp:darkcave@macbeth.shakespeare.lit?join
    

The application MUST either present an interface enabling the user to provide a room nickname or populate the room nickname based on configured preferences.

Example 15. Join Action: Resulting Stanza

<presence to='darkcave@macbeth.shakespeare.lit/thirdwitch'>
  <x xmlns='http://jabber.org/protocol/muc'/>
</presence>
    

The application SHOULD populate the room nickname based on the value provided when joining.

It may be desirable to simultaneously join a room and invite one or more specified other individuals to join the room. The "invite" querytype is used to complete such an action.

Example 16. Invite Action: IRI

xmpp:darkcave@macbeth.shakespeare.lit?invite;jid=hecate@shakespeare.lit
    

If the joining user is not yet in the room, the application MUST send two stanzas: the first to join the room and the second to invite the other individual. If the joining user is in the room already, the application shall send only the invitation stanza.

Example 17. Invite Action: Resulting Stanza(s)

<presence to='darkcave@macbeth.shakespeare.lit/thirdwitch'>
  <x xmlns='http://jabber.org/protocol/muc'/>
</presence>

<message to='darkcave@macbeth.shakespeare.lit'>
  <x xmlns='http://jabber.org/protocol/muc#user'>
    <invite to='hecate@shakespeare.lit'/>
  </x>
</message>
    

3.6 Registration-Related Actions

Sometimes it is necessary to register with an entity (e.g., a groupchat room or gateway to a non-Jabber IM system) before interacting with it further; the protocol for doing so is defined in JEP-0077: In-Band Registration. One querytype value is included in the querytype registry to enable registration management: "register".

Example 18. Register Action: IRI

xmpp:marlowe.shakespeare.lit?register
    

Because registration is a two-step process (see JEP-0077), the application MUST then send an IQ-get to the entity in order to retrieve the required registration fields:

Example 19. Retrieving Registration Fields

<iq to='marlowe.shakespeare.lit' type='get'>
  <query xmlns='jabber:iq:register'/>
</iq>
    

Example 20. Receiving Registration Fields

<iq from='marlowe.shakespeare.lit' type='result'>
  <query xmlns='jabber:iq:register'>
    <username/>
    <password/>
  </query>
</iq>
    

The application MUST then present an appropriate interface that enables the user to complete the registration form. Once the user provides the information, the application MUST send an IQ-set to the entity.

Example 21. Sending Registration Information

<iq to='marlowe.shakespeare.lit' type='set'>
  <query xmlns='jabber:iq:register'>
    <username>juliet</username>
    <password>R0m30</password>
  </query>
</iq>
    

3.7 Pubsub-Related Actions

JEP-0060: Publish-Subscribe defines a generic protocol for subscribing and publishing to "feeds" or "channels" of information. The "pubsub" querytype is defined herein for interaction with pubsub services, with two keys: (1) "node" (to specify pubsub nodes) and (2) "action", whose defined values are "subscribe", "unsubscribe", and "publish".

Example 22. Pubsub Subscribe Action: IRI

xmpp:pubsub.shakespeare.lit?pubsub;action=subscribe;node=globe/performances
    

Example 23. Pubsub Subscribe Action: Resulting Stanza

<iq to='pubsub.shakespeare.lit' type='set'>
  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
    <subscribe node='globe/performances'/>
  </pubsub>
</iq>
    

Example 24. Pubsub Unsubscribe Action: IRI

xmpp:pubsub.shakespeare.lit?pubsub;action=unsubscribe;node=globe/performances
    

Example 25. Pubsub Unsubscribe Action: Resulting Stanza

<iq to='pubsub.shakespeare.lit' type='set'>
  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
    <unsubscribe node='globe/performances'/>
  </pubsub>
</iq>
    

3.8 Disco-Related Actions

JEP-0030: Service Discovery defines a protocol for for discovering information about Jabber entities as well as the items associated with such entities. The "disco" querytype is defined herein for interaction for the purpose of service discovery, with three keys: (1) an OPTIONAL "node" (to specify service discovery nodes), (2) "request", whose defined values are "info" and "items" (corresponding to the disco#info and disco#items namespaces specified in JEP-0030), and (3) "type", whose defined values are "get" and "set" (corresponding to the IQ "get" and "set" methods specified in RFC 3920).

Example 26. Service Discovery Information Request: IRI

xmpp:romeo@montague.net?disco;type=get;request=info
    

Example 27. Service Discovery Information Request: Resulting Stanza

<iq to='romeo@montague.net' type='get'>
  <query xmlns='http://jabber.org/protocol/disco#info'/>
</iq>
    

Example 28. Service Discovery Items Request: IRI

xmpp:romeo@montague.net?disco;type=get;request=items;node=http://jabber.org/protocol/extended-presence
    

Example 29. Service Discovery Items Request: Resulting Stanza

<iq to='romeo@montague.net' type='get'>
  <query xmlns='http://jabber.org/protocol/disco#info'
         node='http://jabber.org/protocol/extended-presence'/>
</iq>
    

4. Internationalization Considerations

Internationalization considerations for XMPP IRIs are specified in draft-saintandre-xmpp-iri-00; the reader is referred to that document for a complete discussion of the relevant issues.

5. Security Considerations

Security considerations for XMPP IRIs are specified in draft-saintandre-xmpp-iri-00.

Furthermore, completion of some of the actions defined herein will cause changes to an entity's account, subscriptions to information, registration with services, communication with other entities, and the like. Naturally, such changes, information, services, and communications are potentially undesirable (e.g., joining a chatroom whose discussion topic is not of interest to, or even patently offensive to, the joining user). The invoked application SHOULD appropriately warn a human user regarding the consequences of the action about to be completed.

6. IANA Considerations

This document requires no interaction with the Internet Assigned Numbers Authority (IANA) [13].

7. Jabber Registrar Considerations

7.1 XMPP IRI Querytype Registry

The Jabber Registrar shall create a registry of querytype values.

7.1.1 Process

In order to submit new values to this registry, the registrant must define an XML fragment of the following form and either include it in the relevant Jabber Enhancement Proposal or send it to the email address <registrar@jabber.org>:

<querytype>
  <name>the name of the querytype (e.g., "pubsub")</name>
  <proto>
    the namespace of associated protocol output 
    (e.g., "http://jabber.org/protocol/pubsub")
  </proto>
  <desc>a natural-language description of the querytype</desc>
  <doc>the document in which the querytype is specified</doc>
  <keys>
    <key>
      <name>the name of the key (e.g., "action")</name>
      <desc>a natural-language description of the key</desc>
      <values>
        <value>
	  <name>the name of a value (e.g., "subscribe")</name>
          <desc>a natural-language description of the value</desc>
        </value>
      </values>
    </key>
  </keys>
</querytype>
      

Note: Within the <querytype/> element, the <keys/> child element is OPTIONAL; within any given <key/> element, the <values/> child element is also OPTIONAL.

The registrant may register more than one querytype at a time, each contained in a separate <querytype/> element.

7.1.2 Initial Registration


<querytype>
  <name>disco</name>
  <proto>http://jabber.org/protocol/disco</proto>
  <desc>enables interaction for the purpose of service discovery</desc>
  <doc>JEP-0147</doc>
  <keys>
    <key>
      <name>node</name>
      <desc>the (optional) service discovery node</desc>
    </key>
    <key>
      <name>request</name>
      <desc>the service discovery request type</desc>
      <values>
        <value>
	  <name>info</name>
          <desc>a service discovery information (disco#info) request</desc>
        </value>
        <value>
	  <name>items</name>
          <desc>a service discovery items (disco#items) request</desc>
        </value>
      </values>
    </key>
    <key>
      <name>type</name>
      <desc>the IQ type</desc>
      <values>
        <value>
	  <name>get</name>
          <desc>an IQ get</desc>
        </value>
        <value>
	  <name>set</name>
          <desc>an IQ set (disco publish)</desc>
        </value>
      </values>
    </key>
  </keys>
</querytype>

<querytype>
  <name>invite</name>
  <proto>http://jabber.org/protocol/muc</proto>
  <desc>enables simultaneously joining a groupchat room and inviting others</desc>
  <doc>JEP-0147</doc>
</querytype>

<querytype>
  <name>join</name>
  <proto>http://jabber.org/protocol/muc</proto>
  <desc>enables joining a groupchat room</desc>
  <doc>JEP-0147</doc>
</querytype>

<querytype>
  <name>message</name>
  <proto>jabber:client</proto>
  <desc>enables sending of an XMPP message stanza</desc>
  <doc>JEP-0147</doc>
  <keys>
    <key>
      <name>subject</name>
      <desc>a subject for the message per the "jabber:client" schema</desc>
    </key>
    <key>
      <name>body</name>
      <desc>a body for the message per the "jabber:client" schema</desc>
    </key>
    <key>
      <name>thread</name>
      <desc>a Thread ID for the message per the "jabber:client" schema</desc>
    </key>
    <key>
      <name>from</name>
      <desc>a from address for the message per the "jabber:client" schema</desc>
    </key>
    <key>
      <name>id</name>
      <desc>an ID for the message per the "jabber:client" schema</desc>
    </key>
    <key>
      <name>type</name>
      <desc>the message type per the "jabber:client" schema</desc>
      <values>
        <value>
	  <name>chat</name>
          <desc>a message of type "chat"</desc>
        </value>
        <value>
	  <name>groupchat</name>
          <desc>a message of type "groupchat"</desc>
        </value>
        <value>
	  <name>headline</name>
          <desc>a message of type "headline"</desc>
        </value>
        <value>
	  <name>normal</name>
          <desc>a message of type "normal"</desc>
        </value>
      </values>
    </key>
  </keys>
</querytype>

<querytype>
  <name>probe</name>
  <proto>jabber:client</proto>
  <desc>enables probing for a contact's current presence information</desc>
  <doc>JEP-0147</doc>
</querytype>

<querytype>
  <name>pubsub</name>
  <proto>http://jabber.org/protocol/pubsub</proto>
  <desc>enables interaction with a publish-subscribe service</desc>
  <doc>JEP-0147</doc>
  <keys>
    <key>
      <name>action</name>
      <desc>the pubsub action</desc>
      <values>
        <value>
	  <name>subscribe</name>
          <desc>enables subscribing to a pubsub node</desc>
        </value>
        <value>
	  <name>unsubscribe</name>
          <desc>enables unsubscribing from a pubsub node</desc>
        </value>
      </values>
    </key>
    <key>
      <name>node</name>
      <desc>the pubsub node</desc>
    </key>
  </keys>
</querytype>

<querytype>
  <name>register</name>
  <proto>jabber:iq:register</proto>
  <desc>enables registering with a server or service</desc>
  <doc>JEP-0147</doc>
</querytype>

<querytype>
  <name>roster</name>
  <proto>jabber:iq:roster</proto>
  <desc>enables adding or editing a roster item</desc>
  <doc>JEP-0147</doc>
</querytype>

<querytype>
  <name>subscribe</name>
  <proto>jabber:client</proto>
  <desc>enables sending a presence subscription request</desc>
  <doc>JEP-0147</doc>
</querytype>

      


Notes

1. An Internationalized Resource Identifier (IRI) Scheme for the Extensible Messaging and Presence Protocol (XMPP) <http://www.ietf.org/internet-drafts/draft-saintandre-xmpp-iri-00.txt> (work in progress).

2. On the difference between IRIs and URIs, see RFC 3987.

3. RFC 3920: Extensible Messaging and Presence Protocol (XMPP): Core <http://www.ietf.org/rfc/rfc3920.txt>.

4. The Jabber Registrar maintains a list of reserved Jabber protocol namespaces as well as registries of parameters used in the context of protocols approved by the Jabber Software Foundation. For further information, see <http://www.jabber.org/registrar/>.

5. RFC 3986: Uniform Resource Identifiers (URI): Generic Syntax <http://www.ietf.org/rfc/rfc3986.txt>.

6. RFC 3987: Internationalized Resource Identifiers (IRIs) <http://www.ietf.org/rfc/rfc3987.txt>.

7. JEP-0045: Multi-User Chat <http://www.jabber.org/jeps/jep-0045.html>.

8. JEP-0077: In-Band Registration <http://www.jabber.org/jeps/jep-0077.html>.

9. JEP-0060: Publish-Subscribe <http://www.jabber.org/jeps/jep-0060.html>.

10. JEP-0030: Service Discovery <http://www.jabber.org/jeps/jep-0030.html>.

11. JEP-0071: XHTML-IM <http://www.jabber.org/jeps/jep-0071.html>.

12. RFC 3921: Extensible Messaging and Presence Protocol (XMPP): Instant Messaging and Presence <http://www.ietf.org/rfc/rfc3921.txt>.

13. 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/>.


Revision History

Version 0.4 (2005-06-06)

Updated to reflect draft-saintandre-xmpp-iri-00. (psa)

Version 0.3 (2005-02-28)

Updated to reflect draft-saintandre-xmpp-uri-08 and subsequent XMPP WG discussion; removed use cases for editing roster items, removing roster items, leaving chatrooms, unsubscribing, and unregistering (these make more sense from within a dedicated client); added use case for simultaneously joining a room and inviting other participants; further specified security considerations. (psa)

Version 0.2 (2004-11-17)

Updated to reflect draft-saintandre-xmpp-uri-07; specified Service Discovery usage. (psa)

Version 0.1 (2004-11-12)

Initial version. (psa)


END