Workflow Tutorial 3 - Cross Domain Orchestration

Introduction

The learning objectives for this exercise are:

1. Learn how to delegate access to resources across domains.

Step 1:

Create a client proxy to the first remote job service and start a job similar to Exercise 2.

StateRepository repository = new MemoryStateRepository();
RemoteJobService jobService1 = (RemoteJobService)  
		repository.getOrCreateObject(RemoteJobService.class,ConversationID.getEPR(JOB_SERVICE_ENDPOINT1));

JobConversation jobConv1 = jobService1.createJob(APPLICATION1, null, "");
DataConversation[] inputs1 = jobConv1.getInputs();
DataConversation[] outputs1 = jobConv1.getOutputs();

inputs1[0].save(new DataHandler(new FileDataSource(INPUT_FILE)));

jobConv1.submitJob(null, new String[]{});
while(jobConv1.stillActive()) {	
	Thread.sleep(2000);
}
JobStatus jobStatus = jobConv.checkJob();
if(jobStatus.getExitStatus() != 0) {
  // handle the failure
  throw new RuntimeException("Swirl job failed. Here is the log:\n" + jobStatus.getLogText());
}

Step 2:

Create the second job at the second Service Provider.

RemoteJobService jobService2 = (RemoteJobService) 
		repository.getOrCreateObject(RemoteJobService.class,ConversationID.getEPR(JOB_SERVICE_ENDPOINT2));
JobConversation jobConv2 = jobService2.createJob(APPLICATION2, null, "");

Step 3:

Instead of uploading a file as input for the job, copy the output from Job1. First we must allow access to the output stager by adding a MatchRule on the output resource. The MatchRule states that jobService2 is allowed 'read' access to the output of job 1.

DataConversation[] inputs2 = jobConv2.getInputs();
DataConversation[] outputs2 = jobConv2.getOutputs();
outputs1[0].addPolicyRule(new PolicyRule(new MatchPattern(jobService2.getServiceProviderID(),jobService2.getServiceProviderIssuer()),"reader"));
inputs2[0].copyFrom(outputs1[0]);

Step 4:

We run the job in the normal way, and then finish both jobs.

jobConv2.submitJob(null, new String[]{});

while(jobConv2.stillActive()) {
	Thread.sleep(2000);
}

JobStatus jobStatus2 = jobConv2.checkJob();

if(jobStatus2.getExitStatus() != 0) {
// handle the failure
throw new RuntimeException("Job failed. Here is the log:\n" +   
						 jobStatus2.getLogText());
}
		
outputs2[0].read(new File(OUTPUT_FILE));

jobConv1.finish();
jobConv2.finish();

Completed Java

If you need some help here is a completed version of the java file.

import java.io.File;
import javax.activation.DataHandler;
import javax.activation.FileDataSource;

import uk.ac.soton.ecs.iam.grid.client.staterepos.MemoryStateRepository;
import uk.ac.soton.ecs.iam.grid.client.staterepos.RemoteJobServiceImpl;
import uk.ac.soton.ecs.iam.grid.comms.client.DataConversation;
import uk.ac.soton.ecs.iam.grid.comms.client.JobConversation;
import uk.ac.soton.ecs.iam.grid.comms.client.RemoteJobService;
import uk.ac.soton.itinnovation.grid.service.types.JobStatus;
import uk.ac.soton.itinnovation.grid.types.ConversationID;
/**
* Simple data and job orchestration example. Edit JOB_SERVICE_ENDPOINT to be the soap endpoint of your job service. */

public class JobExecutionCompleted {
	
	/** Change this Variable to point to your job service!!! */
	private static final String JOB_SERVICE_ENDPOINT = "https://....:8443/gria-basic-app-services/services/JobService";
	
	/** The application to execute, identified by its URI */
	private static final String APPLICATION = "http://it-innovation.soton.ac.uk/grid/imagemagick/swirl";
	
	/** The input file to upload to the job */
	private static final String INPUT_FILE = "data/input-image.png";
	
	/** The ouptut file to download the results to */
	private static final String OUTPUT_FILE = "data/output-image.png";
	
	public static void main(String[] args) throws Exception {

		RemoteJobService jobService = new RemoteJobServiceImpl(
						new MemoryStateRepository(), ConversationID.getEPR(JOB_SERVICE_ENDPOINT));
		JobConversation jobConv = jobService.createJob(APPLICATION, null, "");

		DataConversation[] inputs = jobConv.getInputs();
		DataConversation[] outputs = jobConv.getOutputs();

		inputs[0].save(new DataHandler(new FileDataSource(INPUT_FILE)));

		jobConv.submitJob(null, new String[] {});
		// poll job status
		while(jobConv.stillActive()) {
			System.out.println(".");
			Thread.sleep(2000);
		}

		JobStatus jobStatus = jobConv.checkJob();

		if(jobStatus.getExitStatus() != 0) {
			// handle the failure
			throw new RuntimeException("Swirl job failed. Here is the log:\n" + jobStatus.getLogText());
		}
		outputs[0].read(new File(OUTPUT_FILE));

		System.out.println("Swirl job completed. Output downloaded to: " + OUTPUT_FILE);

		// clean up resources at the server
		jobConv.finish();
	}
}