I have an XProc pipeline with two http-request steps. The first http-request retrieves an XML document containing a sequence of RDF/XML documents. An xquery step extracts only the RDF/XML, which I then want to post to a SPARQL endpoint in the second http-request. In the last step, I want to retrieve the data from the SPARQL endpoint again so that I can do further processing.
I've tried following the solution to a similar question, but I get an error (in XML Calabash) stating, Expression could not be evaluated: c:request/c:body: Prefix c has not been declared. Here is the current pipeline, which is being submitted via XForms to the Calabash Piperack service:
<p:declare-step name="main" version="1.0"
xmlns:p="http://www.w3.org/ns/xproc"
xmlns:c="http://www.w3.org/ns/xproc-step"
xmlns:cx="http://xmlcalabash.com/ns/extensions">
<p:input port="source"/>
<p:output port="result"/>
<p:import href="http://localhost:8984/static/rdf.xpl"/>
<p:http-request>
<p:input port="source">
<p:inline>
<c:request method="GET"
href="http://localhost:9070/all?query=dc.title=test+search&startRecord=1&maximumRecords=50&recordSchema=bibframe"/>
</p:inline>
</p:input>
</p:http-request>
<p:xquery name="xq">
<p:input port="query">
<p:inline>
<c:query>
declare namespace rdf =
"http://www.w3.org/1999/02/22-rdf-syntax-ns#";
element rdf:RDF {
let $rdf := //rdf:RDF
for $r in $rdf/*
return $r
} </c:query>
</p:inline>
</p:input>
<p:input port="parameters">
<p:empty/>
</p:input>
</p:xquery>
<p:insert match="c:request/c:body" position="first-child">
<p:input port="source">
<p:inline>
<c:request method="POST"
href="http://localhost:3030/bibframe/data?graph=cwb:tmp">
<c:body content-type="application/rdf+xml"/>
</c:request>
</p:inline>
</p:input>
<p:input port="insertion">
<p:pipe step="xq" port="result"/>
</p:input>
</p:insert>
<p:http-request/>
<p:sink/>
<cx:rdf-load
href="http://localhost:3030/bibframe/get?graph=cwb:tmp"
language="turtle">
<p:input port="source">
<p:empty/>
</p:input>
</cx:rdf-load>
</p:declare-step>
If I change the XPath in the @match attribute of the p:insert step to /*[local-name() = 'request']/*[local-name() = 'body'], then the prefix error disappears and the post submission works correctly. But is there a way to do this with the prefix?
Finally, the rdf-load step is executing before the other steps have completed, but I need it to always execute last. How can I do this, given that the rdf-load step is not taking direct input from the other steps?
