GT 4.0 WS MDS Aggregator: Developer's Guide: Ping test example

Introduction

This file describes an example of using the Execution Aggregator Source API.

The example provides basic ping information about a registrant. It is intended for illustrative purposes, rather than real deployment use.

The aggregator framework is used by other services to collect information. In this example, it will be shown how to configure the index service to use the execution aggregator source.

Deploying the example

• Install the example script in the correct location. The example script is installed as: $GLOBUS_LOCATION/etc/globus_wsrf_mds_aggregator/example-ping-exec. It is necessary to copy this to the directory where the execution source will look for executables, and ensure that it's executable:

     $ cp $GLOBUS_LOCATION/etc/globus_wsrf_mds_aggregator/example-ping-exec \
          $GLOBUS_LOCATION/libexec/aggrexec/.
     $ chmod a+x $GLOBUS_LOCATION/libexec/aggrexec/example-ping-exec
  

• Configure the index to use the execution source. By default, the index is configured to use a WS-Resource Properties polling mechanism. It is necessary for this example to change the index configuration to use the execution source instead.
• Register some resources. This can be achieved using the mds-servicegroup-add tool. Rather than configuring the client to register with parameters for the Resource Property polling source, parameters for the execution source should be supplied in each registration. Register both resources that you know exist, and also some non-existent resources.
• Observe the results.Start container hosting the index. Start the mds-servicegroup-add tool. Query the contents of the index with:

     $ wsrf-query -s http://localhost:8080/wsrf/services/DefaultIndexService '/*'
  

  Each registration should be represented as an Entry resource property value in the output of wsrf-query; embedded in each entry should be an $examplePingResult element with the results of ping testing.