[kepler-dev] [Bug 3576] New: - support for accessing cascading metadata from within CompositeCoactor

[bugzilla-daemon at ecoinformatics.org]

http://bugzilla.ecoinformatics.org/show_bug.cgi?id=3576

           Summary: support for accessing cascading metadata from within
                    CompositeCoactor
           Product: Kepler
           Version: 1.0.0
          Platform: All
        OS/Version: All
            Status: NEW
          Severity: normal
          Priority: P2
         Component: general
        AssignedTo: mcphillips at ecoinformatics.org
        ReportedBy: mcphillips at ecoinformatics.org
         QAContact: kepler-dev at ecoinformatics.org


The CompositeCoactor class extends TypedCompositeActor (and implements Coactor)
to provide a mechanism for implementing coactors from SDF sub-workflows of
conventional actors.  Data is extracted from the read scope using input ports
named according to the types of data to be extracted, e.g., a port named
'StringToken' will extract a single string token out of the current read scope
and provide it as input to the subworkflow on each firing; a port named
'StringToken+' will provide an array token containing one or more string tokens
extracted from the read scope on each firing, etc.

Currently, metadata or annotations applied to the top-level collection in a
scope-match can also be extracted by specifying the key for the metadata
element required (e.g., by naming a port 'StringToken [key=filename]'). One
thing that can't be done is to access metadata applied to collections above the
read scope and cascading down to it.  This function would be very useful for
reusing information across multiple invocations of a composite coactor.