Data Update Feed

The purpose of this feed API is to enable users to keep their local copies of the consolidated uberblic data set or particular data subsets up-to-date.

Changes to uberblic resources (i.e. nodes in our graph) create change events represented by a numeric, always increasing event id. These event ids are consecutive over the whole uberblic.org data graph. One change event represents a set of changed triples to one particular triple subject URI (hence to one graph node) in one particular graph. Each of the original data sources is represented with a graph, as well as our consolidated graph, named http://uberblic.org/graphs/fusion. Resources also have increasing, individual revision ids.

Note that an uberblic change event may be not as atomic as a change in the original data source. This is especially the case for data sources which do not provide change feeds and object revisions on their own, so that the uberblic can only regularly fetch the latest revision without being able to access individual revisions.

If the unified_diff parameter is set to true (default: false) then all change events between start_id and end_id for one resource get unified into just one change-event. This helps to reduce bandwidth and updates of your triple store in case you are catching up with a long period of updates. If you constantly query the Feed API to fetch real-time changes, set unified_diff to false to help us reduce server load.

http://platform.uberblic.org/api/v1/change_feed?start_id=1234&end_id=2345&unified_diff=true

<change_events start_id="1234" end_id="2345" page_size="20" unified_diff="true">
  <change_event id="1329" resource_uri="http://uberblic.org/resource/e68f52c2-cfc6-4a36-97ae-ac564180dac6#thing" graph_uri="http://uberblic.org/graphs/fusion" revision_id="5" timestamp="2006-01-01T00:00:00Z">
    <diff>
      <addition>
        <![CDATA[
        <http://uberblic.org/resource/e68f52c2-cfc6-4a36-97ae-ac564180dac6#thing> <http://uberblic.org/ontology/label> "hello world!" .
        ]]>
      </addition>
      <removal>
        <![CDATA[
        <http://uberblic.org/resource/e68f52c2-cfc6-4a36-97ae-ac564180dac6#thing> <http://uberblic.org/ontology/label> "hello?" .
        ]]>
      </removal>
    </diff>
  </event>
</change_events>