/*$Id: CeaApplicationDispatcher.java,v 1.5 2006/01/04 09:52:31 clq2 Exp $
    * Created on 25-Feb-2004
    *
    * Copyright (C) AstroGrid. All rights reserved.
    *
    * This software is published under the terms of the AstroGrid
    * Software License version 1.2, a copy of which has been included
    * with this distribution in the LICENSE.txt file.
    *
  **/
  package org.astrogrid.jes.jobscheduler.dispatcher;
  
  import org.astrogrid.applications.delegate.CommonExecutionConnectorClient;
  import org.astrogrid.applications.delegate.DelegateFactory;
  import org.astrogrid.component.descriptor.ComponentDescriptor;
  import org.astrogrid.jes.JesException;
  import org.astrogrid.jes.delegate.JesDelegateFactory;
  import org.astrogrid.jes.delegate.JobMonitor;
  import org.astrogrid.jes.jobscheduler.Dispatcher;
  import org.astrogrid.jes.jobscheduler.Locator;
  import org.astrogrid.jes.types.v1.cea.axis.JobIdentifierType;
  import org.astrogrid.jes.util.JesUtil;
  import org.astrogrid.workflow.beans.v1.Tool;
  import org.astrogrid.workflow.beans.v1.Workflow;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  
  import java.net.URI;
  import java.net.URLConnection;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.List;
  
  import junit.framework.Test;
  import junit.framework.TestCase;
  import junit.framework.TestSuite;
  
  /*** Implementation of a Dispactcher that calls an cea  web service to execute a job step.
   * @author Noel Winstanley nw@jb.man.ac.uk 25-Feb-2004
   *
   */
  public  class CeaApplicationDispatcher implements Dispatcher, ComponentDescriptor {
     private static final Log logger =
        LogFactory.getLog(CeaApplicationDispatcher.class);
     /*** Configuration component for Application Controller Dispatcher
      * @author Noel Winstanley nw@jb.man.ac.uk 07-Mar-2004
      *
      */
     public interface Endpoints {
        URI monitorEndpoint();
        URI resultListenerEndpoint();
     }
     /*** Construct a new ApplicationControllerDispatcher
      * @param locator tool locator component to use to resolve endpoints
      * @param endpoint configuration component that specifies the endpoint of the JobMonitor service. This is used by the
      ApplicationController to
      * return execution information back to the JES server.
      */
     public CeaApplicationDispatcher(Locator locator, Endpoints endpoint) {
        this.locator = locator;
        this.monitorURI = endpoint.monitorEndpoint();
        this.resultListenerURI = endpoint.resultListenerEndpoint();
        assert monitorURI != null;
        assert resultListenerURI != null;
        logger.info("monitor URL set to " + monitorURI.toString());
        logger.info("result URL set to " + resultListenerURI.toString());
     }
     /*** tool locator component */
     protected final Locator locator;
     /*** endpoint of local jobmonitor service - used as a callback */
     protected final URI monitorURI;
     /*** endpoint of local result listener servuce - again, used as a callback */
     protected final URI resultListenerURI;
  
  
     public void dispatchStep(Workflow job, Tool tool,String stepId) throws JesException {
  
        String[] toolLocations = locator.locateTool(tool);
        JobIdentifierType id = JesUtil.createJobId(job.getJobExecutionRecord().getJobId(), stepId);
        boolean connected = false;
        if (logger.isDebugEnabled()) {
            logger.debug("Will attempt to connect to " + Arrays.asList(toolLocations));
        }
        List exceptions = new ArrayList();
        for (int i = 0; i < toolLocations.length && ! connected ; i++) { // try each one in the list, until something sticks.
            try {
                logger.debug("Creating a job on CEA server at " + toolLocations[i] +
                             " for " + tool.getName() + ", "+ id.getValue());
                CommonExecutionConnectorClient appController =    DelegateFactory.createDelegate(toolLocations[i]);
                String applicationId = appController.init(tool,id);
                logger.debug("Registering results listener " + resultListenerURI + " with " + toolLocations[i]);
                appController.registerResultsListener(applicationId,resultListenerURI);
                logger.debug("Registering progress listener " + monitorURI + " with " + toolLocations[i]);
                appController.registerProgressListener(applicationId,monitorURI);
                logger.debug("Activating the job on " + toolLocations[i]);
                appController.execute(applicationId);
                logger.debug("The job on " + toolLocations[i] + " was dispatched successfully.");
                connected = true; // signal that we've connected to a cea, so no need to keep looping.
           }
           catch (Throwable e) {
               logger.warn("Failed to communicate or initialize application with CEA Server",e);
               exceptions.add(e); // only want to fail when we can't connect to any of them -
                                  // but need to preserve the exceptions, for reporting in case all fail.
           }
       }
       if (! connected) {// exhausted all possibilities, so fail
           String str = "Failed to communicate or initialize application with any CEA Server that provides this application:" +
           Arrays.asList(toolLocations);
           Throwable cause = null;
           if (exceptions.size() == 1) {
               cause = (Throwable)exceptions.get(0);
           } else if (exceptions.size() > 1) {
               cause = new AggregateException((Throwable[])exceptions.toArray(new Throwable[]{}));
           }
           logger.warn(str,cause);
          throw new JesException(str,cause);
       }
 
    }
 
    /***
     * @see org.astrogrid.jes.component.ComponentDescriptor#getName()
     */
    public String getName() {
       return "ApplicationController Dispatcher";
    }
 
    /***
     * @see org.astrogrid.jes.component.ComponentDescriptor#getDescription()
     */
    public String getDescription() {
       return "Dispatcher that executes job steps by calling application controllers"
          + " Configured to tell application controllers to call back to:\n"
          + monitorURI.toString();
    }
 
    /***
     * @see org.astrogrid.jes.component.ComponentDescriptor#getInstallationTest()
     */
    public Test getInstallationTest() {
       TestSuite suite = new TestSuite("Tests for ApplicationControllerDispatcher");
       suite.addTest(new InstallationTest("testCanConnectMonitorURL"));
       suite.addTest(new InstallationTest("testCanCallMonitorURL"));
       return suite;
    }
 
    protected class InstallationTest extends TestCase {
       public InstallationTest(String s) {
          super(s);
       }
       public void testCanConnectMonitorURL() throws Exception {
          URLConnection conn = monitorURI.toURL().openConnection();
          assertNotNull(conn);
          conn.connect();
 
       }
       public void testCanCallMonitorURL() throws Exception {
          JobMonitor mon = JesDelegateFactory.createJobMonitor(monitorURI.toString());
          assertNotNull(mon);
          // call, with null parameters. will be ignored by other end - if it gets there. we're checking it gets there..
          mon.monitorJob(null, null);
       }
    }
 
 
 
 }
 
 /*
 $Log: CeaApplicationDispatcher.java,v $
 Revision 1.5  2006/01/04 09:52:31  clq2
 jes-gtr-1462
 
 Revision 1.4.42.1  2005/12/02 11:38:48  gtr
 I changed the logging slightly, logging more to do with transactions on other services.
 
 Revision 1.4  2005/04/25 12:13:54  clq2
 jes-nww-776-again
 
 Revision 1.3.4.1  2005/04/11 13:56:20  nw
 organized imports
 
 Revision 1.3  2005/04/01 10:24:19  nw
 improved logging of cea connect failures
 
 Revision 1.2  2005/03/13 07:13:39  clq2
 merging jes-nww-686 common-nww-686 workflow-nww-996 scripting-nww-995 cea-nww-994
 
 Revision 1.1.2.2  2005/03/11 15:21:35  nw
 adjusted locator so that it returns a list of endpoints to connect to.
 we can get round-robin by shuffling the list.
 dispatcher tries each endpoint in the list until can connect to one wihout throwing an exception.
 
 Revision 1.1.2.1  2005/03/11 14:04:03  nw
 added new kinds of dispatcher.
 
 Revision 1.19  2004/08/13 09:07:58  nw
 tidied imports
 
 Revision 1.18  2004/08/09 17:31:11  nw
 adjusted interface, to work better with dynamically-generated states.
 
 Revision 1.17  2004/08/03 16:31:25  nw
 simplified interface to dispatcher and locator components.
 removed redundant implementations.
 
 Revision 1.16  2004/07/30 15:42:34  nw
 merged in branch nww-itn06-bz#441 (groovy scripting)
 
 Revision 1.15.20.1  2004/07/30 15:10:04  nw
 removed policy-based implementation,
 adjusted tests, etc to use groovy implementation
 
 Revision 1.15  2004/07/09 09:30:28  nw
 merged in scripting workflow interpreter from branch
 nww-x-workflow-extensions
 
 Revision 1.14  2004/07/02 09:07:58  nw
 added in results listener
 
 Revision 1.13  2004/07/01 21:15:00  nw
 added results-listener interface to jes
 
 Revision 1.12  2004/07/01 11:19:05  nw
 updated interface with cea - part of cea componentization
 
 Revision 1.11  2004/05/27 09:49:42  nw
 improved exception reporting 'when applications go bad'
 
 Revision 1.10  2004/04/08 14:43:26  nw
 added delete and abort job functionality
 
 Revision 1.9  2004/03/24 08:05:08  pah
 call the new CommonExecutionConnector Delegate
 
 Revision 1.8  2004/03/15 23:45:07  nw
 improved javadoc
 
 Revision 1.7  2004/03/15 01:30:45  nw
 factored component descriptor out into separate package
 
 Revision 1.6  2004/03/12 15:32:14  nw
 improved logging
 
 Revision 1.5  2004/03/07 21:04:39  nw
 merged in nww-itn05-pico - adds picocontainer
 
 Revision 1.4.4.1  2004/03/07 20:41:06  nw
 added component descriptor interface impl,
 refactored any primitive types passed into constructor
 
 Revision 1.4  2004/03/05 16:16:23  nw
 worked now object model through jes.
 implemented basic scheduling policy
 removed internal facade
 
 Revision 1.3  2004/03/04 01:57:35  nw
 major refactor.
 upgraded to latest workflow object model.
 removed internal facade
 replaced community snippet with objects
 
 Revision 1.2  2004/02/27 00:46:03  nw
 merged branch nww-itn05-bz#91
 
 Revision 1.1.2.1  2004/02/27 00:27:07  nw
 rearranging code
 
 */