Indexer Service

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This is a stateful Web Service that serves as a wrapper to Parallel Indexing application developed by the INSPIRE team.


Notes to administrator:

In order for the Indexer service to work in a scope, and since we can't specify requirements for the software of the execution node through Hadoop Adaptor, it is necessary that indexer.jar file has been uploaded to Content Management System manually, before running an Indexer job. Client org.gcube.execution.indexerservice.tests.UploadIndexerJarClient must be used for that reason. You can call that client as:

java org.gcube.execution.indexerservice.tests.UploadIndexerJarClient <scope> <location of jar file>

e.g.

java org.gcube.execution.indexerservice.tests.UploadIndexerJarClient /gcube/devNext $GLOBUS_LOCATION/sample-indexing-mod7.jar

(make sure that Content Management jars exist in your classpath) and a unique collection will be created in scope "/gcube/devNext" that will contain only the jar file "$GLOBUS_LOCATION/sample-indexing-mod7.jar" from your filesystem. Indexer Service will find that file in Content Management, and send it along with the other resources, when a new Indexer Job is submitted through Hadoop Adaptor.


If the hadoop installation in scope needs to have fully qualified names that contain the uri needed to connect to the hadoop cluster (e.g. it needs hdfs://node1.hadoop.research-infrastructures.eu:8020/user/INSPIRE/smalldata/ instead of /user/INSPIRE/smalldata/ ), you need to add the following xml element in the $GLOBUS_LOCATION/GHNLabels.xml file of the container of the machine with hadoop gateway:

       <Variable>
       <Key>hadoopLocationPrefix</Key>
       <Value>hdfs://node1.hadoop.research-infrastructures.eu:8020</Value>
       </Variable>


Notes to developer:

When indexer service factory receives a call from a user, it tries to find a Workflow Engine instance in that scope, which will use to submit a new job using Hadoop adaptor. In case of success, it will create a Web Service resource for that job, that will contain information of that job such as job name,execution id,workflow engine endpoint etc. A background thread that operates periodically is in charge of collecting all WS-resources, polling the workflow engine instance for the jobs that are still running, and updating the corresponding WS-resources.


Notes to user:

Indexer service can be consumed through the org.gcube.execution.indexerservice.tests.TestIndexerService client. That client submits a Parallel Indexing job by providing the location of input and output, and the number of shards and polls the status of the job until completion. The output of the job is a directory in the hdfs.

Usage:

java org.gcube.execution.indexerservice.tests.TestIndexerService <indexer factory address> <gcube scope> <input location> <output location> <shards number> <optional job name in >=0 words >

Example of use when fully qualified input location is needed by hadoop installation:

java org.gcube.execution.indexerservice.tests.TestIndexerService http://jazzman.di.uoa.gr:8080/wsrf/services/gcube/execution/indexerservice/IndexerServiceFactory /d4science.research-infrastructures.eu/INSPIRE hdfs://node1.hadoop.research-infrastructures.eu:8020/user/INSPIRE/smalldata		hdfs://node1.hadoop.research-infrastructures.eu:8020/tmp/output 5 Indexing by John in /user/INSPIRE/smalldata/texts

Example of use when fully qualified input location is not needed by hadoop installation:

java org.gcube.execution.indexerservice.tests.TestIndexerService http://jazzman.di.uoa.gr:8080/wsrf/services/gcube/execution/indexerservice/IndexerServiceFactory /gcube/devNext hdfs:///user/INSPIRE/smalldata/texts		hdfs:///tmp/output 5 Indexing by John in devNext scope