activity streams.xml

<alps version="1.0">
 <description>
  This is an ALPS description of the semantics defined by the
  ActivityStreams standard. It is based on information published in
  the "JSON Activity Streams 1.0" standard
  [http://activitystrea.ms/specs/json/1.0/]

  The 'activity' in Activity Streams is a description of an action that
  was performed (the verb) at some instant in time by someone or
  something (the actor) against some kind of person, place, or thing
  (the object). There may also be a target (like a photo album or
  wishlist) involved.

  The 'stream' in Activity Streams is a feed of related activities for a
  given person or social object.

  Put together, Activity Streams is a convenient and consistent way to
  syndicate social activities around the web.

  This document does *not* describe Activity Streams
  documents. Instead, it allows reuse of the semantics defined by
  Activity Streams in documents written in any hypermedia type with
  ALPS support (HTML, Collection+JSON, Siren, etc.) The goal of this
  document is to stop other people from repeating the work Activity
  Streams has done to catalogue the sort of things people do on the
  Web.

  The semantics defined by this document are comparable in strictness
  to an HTML microformat; much looser than the semantics defined by
  Activity Streams. An example: Activity Streams says that the 'actor'
  in an activity must be an Activity Streams 'object'. This document
  requires that an event have an 'actor', but an 'actor' can be
  anything at all, so long as it's tagged with the 'actor' descriptor.

  <div class="activity">
   <div class="actor">
    J.R. "Bob" Dobbs
   </div>
  </div>

  An 'actor' that also happens to implement the semantics of 'object'
  would be tagged with both 'actor' and 'object':

  <div class="activity">
   <div class="actor object">
    <span class="displayName">
     J.R. "Bob" Dobbs
    </span>
    (<a href="/profiles/jdobbs" class="url" rel="person">Profile</a>)
   </div>
  </div>
 </description>

 <element id="activity" appears="MUST" cardinality="many">

  <description>
   A description of an action that was performed (the verb) at some
   instant in time by someone or something (the actor) against some
   kind of person, place, or thing (the object). There may also be a
   target (like a photo album or wishlist) involved.
  </description>

  <child id="actor" appears="MUST" cardinality="single">
   <description>
    Describes the entity that performed the activity.
   </description>
  </child>

  <child id="content" appears="MAY" cardinality="single">
   <description>
    Natural-language description of the activity containing containing
    HTML markup. Visual elements such as thumbnail images MAY be
    included.
   </description>
  </child>

  <child id="generator" appears="MAY" cardinality="single">
   <description>
    Describes the application that generated the activity.
   </description>
  </child>

  <child id="icon" appears="MAY" cardinality="single">
   <description>
    Description of a resource providing a visual representation of the
    object, intended for human consumption. The image SHOULD have an
    aspect ratio of one (horizontal) to one (vertical) and SHOULD be
    suitable for presentation at a small size.
   </description>
  </child>

  <child href="#id" appears="SHOULD" cardinality="single"/>

  <child appears="SHOULD" cardinality="single">
   <description>
     Describes the primary object of the activity. For instance, in
     the activity, "John saved a movie to his wishlist", the object of
     the activity is "movie". If 'object' is not present, the
     primary object of the activity MAY be implied by context.
   </description>
  </child>

  <child href="#published" appears="MUST" cardinality="single"/>

  <child id="provider" appears="MAY" cardinality="single">
   <description>
    Describes the application that published the activity. Note that
    this is not necessarily the same entity that generated the
    activity.
   </description>
  </child>

  <child id="target" appears="MAY" cardinality="single">
   <description>
    Describes the target of the activity. The precise meaning of the
    activity's target is dependent on the activity's 'verb', but will
    often be the object of the English preposition "to". For instance,
    in the activity, "John saved a movie to his wishlist", the target
    of the activity is "wishlist". The activity target MUST NOT be
    used to identity an indirect object that is not a target of the
    activity.
   </description>
  </child>

  <child id="title" appears="MAY" cardinality="single">
   <description>
    Natural-language title or headline for the activity containing
    HTML markup.
   </description>
  </child>

  <child href="#updated" appears="MAY" cardinality="single"/>

  <child href="#url" type="safe" appears="MAY" cardinality="single">
   <description>
     An IRI [RFC3987] identifying a resource providing an HTML
     representation of the activity.
   </description>
  </child>

  <child id="verb" appears="SHOULD" cardinality="single">
   <description>
     Identifies the action that the activity describes. Value MUST be
     non-empty and match either the "isegment-nz-nc" or the "IRI"
     production in [RFC3339]. The unsafe link relations defined in
     this document make good values for "verb". Note that the use of a
     relative reference other than a simple name is not allowed. If
     the verb is not specified, or if the value is null, the verb is
     assumed to be "post".
   </description>
  </child>
 </element>

 <element id="media-link" appears="MUST NOT">

  <child name="duration" appears="MAY" cardinality="single">
   <description>
    A hint to the consumer about the length, in seconds, of the media
    resource identified by the 'url' property. A media link MAY
    contain a 'duration' property when the target resource is a
    time-based media item such as an audio or video file.
   </description>
  </child>

  <child name="height" appears="MAY" cardinality="single">
   <description>
    A hint to the consumer about the height, in pixels, of the media
    resource identified by the "url" property. A media link MAY contain
    a "width" property when the target resource is a visual media item
    such as an image, video or embeddable HTML page.
   </description>
  </child>

  <child name="width" appears="MAY" cardinality="single">
   <description>
    A hint to the consumer about the width, in pixels, of the media
    resource identified by the "url" property. A media link MAY contain
    a "width" property when the target resource is a visual media item
    such as an image, video or embeddable HTML page.
   </description>
  </child>

  <child href="#url" appears="MUST" cardinality="single">
   <description>
 	The IRI of the media resource being linked.
   </description>
  </child>
 </element>

 <element id="object" appears="MUST NOT">
  <description>
   An object is a collection of data with very generic aplication. An
   object may be 'actor', 'generator', 'object', 'provider', or
   'target' of an activity. In the activity "John saved a movie to his
   wishlist," the objects are: John himself ('actor'), the movie
   ('object'), the wishlist ('target'), the service that makes an
   announcement when John's wishlist changes ('provider'), and the
   service John uses to manage his wishlist ('genarator').
  </description>

  <child id="attachment" appears="MAY" cardinality="many">
   <description>
     A collection of one or more additional, associated objects,
     similar to the concept of attached files in an email message.
   </description>
  </child>

  <child id="author" appears="MAY" cardinality="single">
   <description>
     Describes the entity that created or authored the object. Note
     that the author field identifies the entity that created the
     object and does not necessarily identify the entity that
     published the object. For instance, it may be the case that an
     object created by one person is posted and published to a system
     by an entirely different entity.
   </description>
  </child>

  <child id="content" appears="MAY" cardinality="single">
   <description>
    Natural-language description of the object including HTML
    markup. Visual elements such as thumbnail images MAY be included.
   </description>
  </child>

  <child id="displayname" appears="MAY" cardinality="single">
   <description>
     A natural-language, human-readable and plain-text name for the
     object. HTML markup MUST NOT be included.
   </description>
  </child>

  <child id="downstreamDuplicate" type="safe" appears="MAY" cardinality="many">
   <description>
    An absolute IRI [RFC3987] identifying an object that duplicates
    this object's content. An object SHOULD use the
    downstreamDuplicate element when there are known objects,
    possibly in a different system, that duplicate the content in this
    object. This MAY be used as a hint for consumers to use when
    resolving duplicates between objects received from different
    sources.
   </description>
  </child>

  <child href="#id" cardinality="single"/>

  <child id="image" appears="MAY" cardinality="single">
   <description>
    Description of a resource providing a visual representation of the
    object, intended for human consumption.
   </description>
  </child>

  <child href="#published" appears="MAY" cardinality="single"/>

  <child id="summary" appears="MAY" cardinality="single">
   <description>
    Natural-language summarization of the object containing HTML
    markup. Visual elements such as thumbnail images MAY be included.
   </description>
  </child>

  <child href="#updated" cardinality="single"/>

  <child id="upstreamDuplicate" rel="safe" appears="MAY" cardinality="many">
   <description>
    An absolute IRI [RFC3987] identifying an object that duplicates
    this object's content. An object SHOULD use the
    downstreamDuplicate property when a publisher is knowingly
    duplicating with a new ID the content from another object. This
    MAY be used as a hint for consumers to use when resolving
    duplicates between objects received from different sources.
   </description>
  </child>

  <child href="#url" appears="MAY" cardinality="single">
   <description>
     Identifies a link to an HTML representation of the object. The
     link relation should describe the object. (e.g. "activity",
     "alert", "application", ..., as given in the Activity Schema
     document) This link relation replaces the 'objectType' attribute
     defined by Activity Streams.
   </description>
  </child>
 </element>

 <!--Elements common to "activity", "media-link", and "object".-->

 <element id="id" type="safe" appears="MUST NOT">
  <description>
   Provides a permanent, universally unique identifier for something
   in the form of an absolute IRI [RFC3987]. If the 'id' element is
   not present but the 'url' element is, consumers MAY use the value
   of 'url' as a less-reliable, non-unique identifier.
   </description>
 </element>

 <element id="published" appears="MUST NOT">
   <description>
    The date and time at which something was first published. The
    format is as described in [RFC3339].
   </description>
 </element>

 <element id="updated" appears="MUST NOT">
  <description>
   The date and time at which something previously published was
   modified. The format is as described in [RFC3339].
  </description>
 </element>

 <element id="url" type="safe" appears="MUST NOT">
  <description>
    An IRI [RFC3987] identifying a resource providing a representation
    of the thing being described.
  </description>
 </element>

<!-- This is the only object type defined by the Activity Streams
     standard. It may be used as either a safe link relation or a
     semantic descriptor. The Activity Schema draft defines many more
     object types. -->

 <element id="activity-object" name="activity" type="descriptor safe">
  <description>
  An object representation of an activity.
  </description>
 </element>

<!-- This is the only verb defined by the Activity Stream standard.
     It may be used anywhere as an unsafe link relation.-->

 <element id="post" type="unsafe">
  <description>
   The act of authoring an object and then publishing it online.
  </description>
 </element>
</alps>