Custom transform throws ClassCastException

[sravotto]

We have a custom transform that creates a result with a snippet and metadata. The snippet contains arbitrary XML, for instance:

<search:response snippet-format=“highlight" total="1" start="1" page-length="1" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns="" xmlns:search="http://marklogic.com/appservices/search">
  <search:result index="1" uri="/doc/2.xml" path="fn:doc(&quot;/doc/2.xml&quot;)" score="92160" confidence="0.674626" fitness="0.674626">
    <search:snippet>
      <headline>Q1 <match>outlook</match></headline>
    </search:snippet>
    <search:metadata>
       <id>a</id>
    </search:metadata>
  </search:result>
  <search:qtext>outlook snippet:highlight</search:qtext>
  <search:metrics>
    <search:query-resolution-time>PT0.008042S</search:query-resolution-time>
    <search:facet-resolution-time>PT0.000323S</search:facet-resolution-time>
    <search:snippet-resolution-time>PT0.018339S</search:snippet-resolution-time>
    <search:total-time>PT0.027161S</search:total-time>
  </search:metrics>
</search:response>

This java snippet:

QueryManager q = client.newQueryManager();
StringQueryDefinition s = q.newStringDefinition("myoptions");
s.setCriteria("a snippet:highlight");
SearchHandle sh = q.search(s, new SearchHandle());

throws the following exception:

Exception in thread "main" java.lang.ClassCastException: com.sun.xml.internal.stream.events.StartElementEvent cannot be cast to javax.xml.stream.events.EndElement
at com.sun.xml.internal.stream.events.DummyEvent.asEndElement(DummyEvent.java:122)
at com.marklogic.client.io.SearchHandle$SearchResponseImpl.collectSnippet(SearchHandle.java:1191)
at com.marklogic.client.io.SearchHandle$SearchResponseImpl.handleSnippet(SearchHandle.java:1169)
at com.marklogic.client.io.SearchHandle$SearchResponseImpl.collectResult(SearchHandle.java:1106)
at com.marklogic.client.io.SearchHandle$SearchResponseImpl.handleResult(SearchHandle.java:1085)
at com.marklogic.client.io.SearchHandle$SearchResponseImpl.handleTop(SearchHandle.java:1017)
at com.marklogic.client.io.SearchHandle$SearchResponseImpl.collectTop(SearchHandle.java:1050)
at com.marklogic.client.io.SearchHandle$SearchResponseImpl.handleResponse(SearchHandle.java:1039)
at com.marklogic.client.io.SearchHandle$SearchResponseImpl.handleTop(SearchHandle.java:1016)
at com.marklogic.client.io.SearchHandle$SearchResponseImpl.parse(SearchHandle.java:984)
at com.marklogic.client.io.SearchHandle$SearchResponseImpl.access$100(SearchHandle.java:948)
at com.marklogic.client.io.SearchHandle.receiveContent(SearchHandle.java:157)
at com.marklogic.client.io.SearchHandle.receiveContent(SearchHandle.java:72)
at com.marklogic.client.impl.QueryManagerImpl.search(QueryManagerImpl.java:199)
at com.marklogic.client.impl.QueryManagerImpl.search(QueryManagerImpl.java:162)

[sammefford]

Silvano, any way you could share the custom transform and options? It would be nice if I could duplicate the error on my end.

[sammefford]

From Silvano:
Transform:

xquery version "1.0-ml";

module namespace ex = "http://marklogic.com/rest-api/transform/test";


declare function ex:transform(
  $context as map:map,
  $params as map:map,
  $content as document-node())
as document-node() {
 document{

<search:response snippet-format="highlight" total="1" start="1" page-length="1" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns="" xmlns:search="http://marklogic.com/appservices/search">
  <search:result index="1" uri="/doc/2.xml" path="fn:doc('/doc/2.xml')" score="92160" confidence="0.674626" fitness="0.674626">
    <search:snippet>
      <headline>Q1 <match>outlook</match></headline>
    </search:snippet>
    <search:metadata>
       <id>a</id>
    </search:metadata>
  </search:result>
  <search:qtext>outlook snippet:highlight</search:qtext>
  <search:metrics>
    <search:query-resolution-time>PT0.008042S</search:query-resolution-time>
    <search:facet-resolution-time>PT0.000323S</search:facet-resolution-time>
    <search:snippet-resolution-time>PT0.018339S</search:snippet-resolution-time>
    <search:total-time>PT0.027161S</search:total-time>
  </search:metrics>
</search:response>}
};

Once you install it

curl -H "Content-type: application/xquery"    -X PUT --digest  --user admin:admin http://localhost:8010/v1/config/transforms/test --data @transform.xqy

you should be able to invoke it:

curl --digest --user admin:admin "http://localhost:8010/v1/search?q=a&transform=test”

[sammefford]

I think all I'm missing now is the saved options "myoptions"

[sravotto]

Hi Sam,
try with this client:

package example;

import java.io.IOException;

import com.marklogic.client.DatabaseClient;
import com.marklogic.client.DatabaseClientFactory;
import com.marklogic.client.document.ServerTransform;
import com.marklogic.client.io.SearchHandle;
import com.marklogic.client.query.MatchDocumentSummary;
import com.marklogic.client.query.QueryManager;
import com.marklogic.client.query.StringQueryDefinition;

public class SearchExample {

    public static void main(String[] args) throws IOException {
        DatabaseClient client =  
                DatabaseClientFactory.newClient("localhost", 8010, "admin",
                        "admin", DatabaseClientFactory.Authentication.DIGEST);
        QueryManager q = client.newQueryManager();
        StringQueryDefinition s = q.newStringDefinition("");
        ServerTransform t = new ServerTransform("test");
        s.setCriteria("a");
        s.setResponseTransform(t);
        SearchHandle resultsHandle = q.search(s, new SearchHandle());
        MatchDocumentSummary[] results = resultsHandle.getMatchResults();
        System.out.println("Results:" + results.length );   
        client.release();
    }
}

[sammefford]

Thanks, Silvano. I was able to duplicate the error, and create a patch. Once my patch has been reviewed, I'll commit it and point you to it.

[sammefford]

Patch is committed to b2_0 and dev branches. You can build using Java 1.6 and maven with this command:

mvn -Dmaven.test.skip -Dmaven.javadoc.skip package

However, it's important to note that this is not officially a supported release or patch. If the client intends to use this in production before the next supported release, it would be best to open a support ticket so support can work with you to run this through a full regression test and take other steps to support this moving forward.