XEP-0197: User Viewing

This document defines an XMPP protocol extension for communicating information about the television shows, movies, or other videos that a user watches.

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

Email: stpeter@jabber.org
JabberID: stpeter@jabber.org

Kevin Hoekman

Email: kevin.hoekman@pandora.be
JabberID: kevinh@jabber.org

Legal Notice

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 television shows, movies, or other videos that a user watches. This information may be of interest to a user's contacts and can also be used in social networking applications (e.g., IPTV systems).

2. Protocol

2.1 Container Element and Child Elements

Information about video viewing is provided by the user (or automated integration with video systems) and is propagated on the network by the user's client. The information container for video viewing data is a <video/> element that is qualified by the 'http://jabber.org/protocol/viewing' namespace. The video information itself is provided as the XML character data of the following children of the <video/> element:

Table 1: Child Elements

Element	Description	Example	Datatype
author	The author of the program	Robert Duncan	xs:string
cast	The cast members of the program	Trace Beaulieu, Frank Conniff, Joel Hodgson, Jim Mallon, Kevin Murphy, Michael J. Nelson, Mary Jo Pehl	xs:string
channel_name	The name of the channel showing the program	Sci-Fi Channel	xs:string
description	A description of the program	Terror From The Year 5000	xs:string
duration	The duration of the program (in seconds)	1800	xs:positiveInteger
end_time	The end time of the program	2006-08-29T03:30Z	xs:dateTime
episode	The episode number of the program	807	xs:string
program_name	The name of the program	Mystery Science Theater 3000	xs:string
program_type	The type of the program	Comedy	xs:string
start_time	The start time of the program	2006-08-29T03:00Z	xs:dateTime
subprogram_type	The type of the sub-program (e.g., outtakes on an extended DVD)	Cast interview	xs:string
uri	A URI for the video or relevant service	http://www.mst3kinfo.com/	xs:anyURI
user_comment	A user's free-form comments about the program	This is one of my favorite episodes! MST3K forever!	xs:string
user_rating	The user's personal rating of the program (on a scale of 1 to 10, with 10 being highest)	9	xs:string

All elements are OPTIONAL.

NOTE: The datatypes specified above are defined in XML Schema Part 2 [3].

2.2 Transport Mechanism

When a user starts watching a video, its client may publish that fact to a special pubsub or PEP node (if a PEP node, the NodeID is "http://jabber.org/protocol/viewing"). The viewing information SHOULD be communicated and transported by means of the XEP-0060 protocol, especially the subset specified in XEP-0163 (as shown in the following examples). Because viewing 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 Viewing Information

<iq type='set' from='stpeter@jabber.org/work' id='viewing1'>
  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
    <publish node='http://jabber.org/protocol/viewing'>
      <item id='8eaa8ae16651455376dab4eae45772337e9ec372'>
        <video xmlns='http://jabber.org/protocol/viewing'>
          <name>Mystery Science Theater 3000</name>
          <episode>807</episode>
          <description>Terror From The Year 5000</description>
          <uri>http://www.mst3kinfo.com/</uri>
        </video>
      </item>
    </publish>
  </pubsub>
</iq>

The viewing information is then delivered to all subscribers:

Example 2. Viewing 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://jabber.org/protocol/viewing'>
      <item id='8eaa8ae16651455376dab4eae45772337e9ec372'>
        <video xmlns='http://jabber.org/protocol/viewing'>
          <name>Mystery Science Theater 3000</name>
          <episode>807</episode>
          <description>Terror From The Year 5000</description>
          <uri>http://www.mst3kinfo.com/</uri>
        </video>
      </item>
    </items>
  </event>
</message>
.
.
.

When the user stops watching the video, the user's client SHOULD send an empty <video/> element to the node with the same ItemID:

Example 3. User Publishes Stop Information

<iq type='set' from='stpeter@jabber.org/work' id='viewing2'>
  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
    <publish node='http://jabber.org/protocol/viewing'>
      <item id='8eaa8ae16651455376dab4eae45772337e9ec372'>
        <video xmlns='http://jabber.org/protocol/viewing'/>
      </item>
    </publish>
  </pubsub>
</iq>

Example 4. Stop 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://jabber.org/protocol/viewing'>
      <item id='8eaa8ae16651455376dab4eae45772337e9ec372'>
        <video xmlns='http://jabber.org/protocol/viewing'/>
      </item>
    </items>
  </event>
</message>
.
.
.

3. Security Considerations

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

4. IANA Considerations

This document requires no interaction with the Internet Assigned Numbers Authority (IANA) [4].

5. XMPP Registrar Considerations

5.1 Protocol Namespaces

The XMPP Registrar [5] shall include 'http://jabber.org/protocol/viewing' in its registry of protocol namespaces.

6. XML Schema

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

<xs:schema
    xmlns:xs='http://www.w3.org/2001/XMLSchema'
    targetNamespace='http://jabber.org/protocol/viewing'
    xmlns='http://jabber.org/protocol/viewing'
    elementFormDefault='qualified'>

  <xs:element name='room'>
    <xs:complexType>
      <xs:sequence minOccurs='0'>
        <xs:element name='author' type='xs:string' minOccurs='0'/>
        <xs:element name='cast' type='xs:string' minOccurs='0'/>
        <xs:element name='channel_name' type='xs:string' minOccurs='0'/>
        <xs:element name='description' type='xs:string' minOccurs='0'/>
        <xs:element name='duration' type='xs:positiveInteger' minOccurs='0'/>
        <xs:element name='end_time' type='xs:dateTime' minOccurs='0'/>
        <xs:element name='episode' type='xs:string' minOccurs='0'/>
        <xs:element name='program_name' type='xs:string' minOccurs='0'/>
        <xs:element name='program_type' type='xs:string' minOccurs='0'/>
        <xs:element name='start_time' type='xs:dateTime' minOccurs='0'/>
        <xs:element name='subprogram_type' type='xs:string' minOccurs='0'/>
        <xs:element name='uri' type='xs:anyURI' minOccurs='0'/>
        <xs:element name='user_comment' type='xs:string' minOccurs='0'/>
        <xs:element name='user_rating' type='xs:string' minOccurs='0'/>
      </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. XML Schema Part 2: Datatypes <http://www.w3.org/TR/xmlschema-2/>.

4. 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/>.

5. 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/>.