Follow Content Item Relations
This section shows how a content item's relations are included in Atom entry resources, and how you can navigate from a content item to it's related content items.
If a retrieved content item has related content items, then they are
always included in the returned Atom entry resource. They appear as
link
elements, with the rel
attribute set to related
. The following example shows
the Atom entry resource for a content item with two related content
items (highlighted in bold):
<entry xmlns="http://www.w3.org/2005/Atom"xmlns:vdf="http://www.vizrt.com/types" xmlns:ns2="http://www.w3.org/1999/xhtml" xmlns:ns="http://www.w3.org/2005/Atom" xmlns:metadata="http://xmlns.escenic.com/2010/atom-metadata" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:app="http://www.w3.org/2007/app"> <id>http://host-ip-address/webservice/escenic/content/5403</id> <title type="text">UK and US terror alerts</title> <updated>2010-10-03T22:07:41.000Z</updated> <app:edited>2011-01-14T14:24:16.000Z</app:edited> <published>2010-10-03T22:07:41.000Z</published> <dcterms:created>2010-10-03T22:07:41.000Z</dcterms:created> <author> <name>Mark mark</name> <uri>http://host-ip-address/webservice/escenic/person/103</uri> </author> <dcterms:identifier>5403</dcterms:identifier> <metadata:reference source="ece-auto-gen" sourceid="38f4f7a2-c2bb-4026-a79f-3bde3c3592df" /> <link href="http://host-ip-address/webservice/escenic/section/44" rel="http://www.vizrt.com/types/relation/home-section" title="News" type="application/atom+xml; type=entry" /> <link href="http://ecedemo5/wf-escenic-times/news/article5403.ece" rel="alternate" /> <link href="http://host-ip-address/webservice/escenic/publication/wf-escenic-times" rel="http://www.vizrt.com/types/relation/publication" title="wf-escenic-times" type="application/atom+xml; type=entry" /> <metadata:creator> <name>Mark mark</name> </metadata:creator> <metadata:publication href="http://host-ip-address/webservice/escenic/publication/wf-escenic-times"> <link href="http://host-ip-address/webservice/escenic/section/44" rel="http://www.vizrt.com/types/relation/home-section" title="News" type="application/atom+xml; type=entry" /> <link href="http://host-ip-address/webservice/escenic/section/44" rel="http://www.vizrt.com/types/relation/section" title="News" type="application/atom+xml; type=entry" /> </metadata:publication> <link href="http://host-ip-address/webservice/escenic/content/5403" rel="edit" /> <link href="http://host-ip-address/webservice/escenic/content/5403" rel="self" /> <link href="http://host-ip-address/webservice/escenic/lock/article/5403" rel="http://www.vizrt.com/types/relation/lock" /> <content type="application/vnd.vizrt.payload+xml"> <vdf:payload model="http://host-ip-address/webservice/escenic/model/news"> ...content... </vdf:payload> </content> <link href="http://host-ip-address/webservice/escenic/content/1513" rel="related" type="application/atom+xml; type=entry" metadata:group="STORYREL"> <vdf:payload model="http://host-ip-address/webservice/content-summaries/news"> <vdf:field name="TITLE"> <vdf:value>Obama rejects 'Biden option' on Afghanistan</vdf:value> </vdf:field> <vdf:field name="LEADTEXT"> <vdf:value>President Obama ....</vdf:value> </vdf:field> </vdf:payload> </link> <link href="http://host-ip-address/webservice/escenic/content/5391" rel="related" type="application/atom+xml; type=entry" metadata:group="STORYREL"> <vdf:payload model="http://host-ip-address/webservice/content-summaries/news"> <vdf:field name="TITLE"> <vdf:value>Travel alert issued for U.S. citizens in Europe</vdf:value> </vdf:field> <vdf:field name="LEADTEXT"> <vdf:value>The United States ...</vdf:value> </vdf:field> </vdf:payload> </link> </entry>
The rel="related"
attribute setting indicates that
the link represents one of the content item's relations. The
metadata:group
attribute specifies the relation type
group that the relation belongs to. Relation type groups are defined in
the content-type
publication resource (see
relation-type-group)
and appear as separate relation drop zones in
Content Studio.
Note that each relation link
element also contains
the relation's summary fields packaged in a VDF
payload
element. This makes it possible for
interactive clients to display the relation summaries along with a
content item, in the same way as
Content Studio.
A client can retrieve related content items by following the links, for example:
curl -u user:password -X GET http://host-ip-address/webservice/escenic/content/1513