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• HTTP Verb: POST
• URL: /objects/$pid/fedora-system:SomeBuiltInSDef/updateDatastream?dsID=$dsID&type=sparql-update
• Body: A SPARQL/Update document (UTF-8?) to apply to the datastream
• Successful response:
  • Code: 201 200
  • Location header: URL to datastream version
  • Content-type header: text/plain; charset=utf-8
  • Body: URL to datastream version
• Failed response (bad request):
  • Code: 400
  • Content-type header: text/plain; charset=utf-8
  • Body: (one-line message)
    • Unrecognized update type: $type
    • No such object: $pid
    • No such datastream in $pid: $dsID

Notes:

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• Adding or modifying the entire content of a datastream would still be possible via a POST or PUT, respectively, to the datastream URL as it is today.
• The syntax for invoking disseminations has not yet been decided for the REST API; the URL above with fedora-system:SomeBuiltInSDef assumes an obvious possible syntax.

Outstanding Issues:

1. Does SPARQL Update have a mime type?  If so that might make sense to use as the value of the type parameter
2. The strawman does not yet include a way to get relationships.  Perhaps this could also be a built-in function of SomeBuiltInSDef.
   1. Q: Would it require one to specify which datastream (e.g. RELS-EXT) the relationships reside in?
   2. Q: What form of query would it accept?  A simple S,P,O style query, or SPARQL?

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