org.argeo.slc.core/src/org/argeo/slc/core/execution/ProcessThread.java

   1 /*
   2  * Copyright (C) 2007-2012 Argeo GmbH
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *         http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 package org.argeo.slc.core.execution;
  17
  18 import java.util.ArrayList;
  19 import java.util.Collections;
  20 import java.util.HashSet;
  21 import java.util.List;
  22 import java.util.Set;
  23
  24 import org.apache.commons.logging.Log;
  25 import org.apache.commons.logging.LogFactory;
  26 import org.argeo.slc.SlcException;
  27 import org.argeo.slc.execution.ExecutionModulesManager;
  28 import org.argeo.slc.execution.ExecutionProcess;
  29 import org.argeo.slc.execution.ExecutionStep;
  30 import org.argeo.slc.execution.RealizedFlow;
  31 import org.springframework.security.core.Authentication;
  32 import org.springframework.security.core.context.SecurityContextHolder;
  33
  34 /**
  35  * Main thread coordinating an {@link ExecutionProcess}, launching parallel or
  36  * sequential {@link ExecutionThread}s.
  37  */
  38 public class ProcessThread extends Thread {
  39         private final static Log log = LogFactory.getLog(ProcessThread.class);
  40
  41         private final ExecutionModulesManager executionModulesManager;
  42         private final ExecutionProcess process;
  43         private final ProcessThreadGroup processThreadGroup;
  44
  45         private Set<ExecutionThread> executionThreads = Collections
  46                         .synchronizedSet(new HashSet<ExecutionThread>());
  47
  48         // private Boolean hadAnError = false;
  49         private Boolean killed = false;
  50
  51         public ProcessThread(ThreadGroup processesThreadGroup,
  52                         ExecutionModulesManager executionModulesManager,
  53                         ExecutionProcess process) {
  54                 super(processesThreadGroup, "SLC Process #" + process.getUuid());
  55                 this.executionModulesManager = executionModulesManager;
  56                 this.process = process;
  57                 processThreadGroup = new ProcessThreadGroup(process);
  58         }
  59
  60         public final void run() {
  61                 // authenticate thread
  62                 Authentication authentication = getProcessThreadGroup()
  63                                 .getAuthentication();
  64                 if (authentication == null)
  65                         throw new SlcException("Can only execute authenticated threads");
  66                 SecurityContextHolder.getContext().setAuthentication(authentication);
  67
  68                 log.info("\n##\n## SLC Process #" + process.getUuid()
  69                                 + " STARTED\n##\n");
  70
  71                 // Start logging
  72                 new LoggingThread().start();
  73
  74                 process.setStatus(ExecutionProcess.RUNNING);
  75                 try {
  76                         process();
  77                 } catch (InterruptedException e) {
  78                         die();
  79                         return;
  80                 } catch (Exception e) {
  81                         String msg = "Process " + getProcess().getUuid()
  82                                         + " failed unexpectedly.";
  83                         log.error(msg, e);
  84                         getProcessThreadGroup().dispatchAddStep(
  85                                         new ExecutionStep("Process", ExecutionStep.ERROR, msg + " "
  86                                                         + e.getMessage()));
  87                 }
  88
  89                 // waits for all execution threads to complete (in case they were
  90                 // started asynchronously)
  91                 for (ExecutionThread executionThread : executionThreads) {
  92                         if (executionThread.isAlive()) {
  93                                 try {
  94                                         executionThread.join();
  95                                 } catch (InterruptedException e) {
  96                                         die();
  97                                         return;
  98                                 }
  99                         }
 100                 }
 101
 102                 computeFinalStatus();
 103         }
 104
 105         /** Make sure this is called BEFORE all the threads are interrupted. */
 106         private void computeFinalStatus() {
 107                 // String oldStatus = process.getStatus();
 108                 // TODO: error management at flow level?
 109                 if (killed)
 110                         process.setStatus(ExecutionProcess.KILLED);
 111                 else if (processThreadGroup.hadAnError())
 112                         process.setStatus(ExecutionProcess.ERROR);
 113                 else
 114                         process.setStatus(ExecutionProcess.COMPLETED);
 115                 // executionModulesManager.dispatchUpdateStatus(process, oldStatus,
 116                 // process.getStatus());
 117                 log.info("\n## SLC Process #" + process.getUuid() + " "
 118                                 + process.getStatus() + "\n");
 119         }
 120
 121         /** Called when being killed */
 122         private synchronized void die() {
 123                 killed = true;
 124                 computeFinalStatus();
 125                 for (ExecutionThread executionThread : executionThreads) {
 126                         try {
 127                                 executionThread.interrupt();
 128                         } catch (Exception e) {
 129                                 log.error("Cannot interrupt " + executionThread);
 130                         }
 131                 }
 132                 processThreadGroup.interrupt();
 133         }
 134
 135         /**
 136          * Implementation specific execution. To be overridden in order to deal with
 137          * custom process types. Default expects an {@link SlcExecution}.
 138          */
 139         protected void process() throws InterruptedException {
 140                 List<RealizedFlow> flowsToProcess = new ArrayList<RealizedFlow>();
 141                 flowsToProcess.addAll(process.getRealizedFlows());
 142                 while (flowsToProcess.size() > 0) {
 143                         RealizedFlow realizedFlow = flowsToProcess.remove(0);
 144                         execute(realizedFlow, true);
 145                 }
 146         }
 147
 148         /** @return the (distinct) thread used for this execution */
 149         protected final void execute(RealizedFlow realizedFlow, Boolean synchronous)
 150                         throws InterruptedException {
 151                 if (killed)
 152                         return;
 153
 154                 ExecutionThread thread = new ExecutionThread(processThreadGroup,
 155                                 executionModulesManager, realizedFlow);
 156                 executionThreads.add(thread);
 157                 thread.start();
 158
 159                 if (synchronous)
 160                         thread.join();
 161
 162                 return;
 163         }
 164
 165         // public void notifyError() {
 166         // hadAnError = true;
 167         // }
 168         //
 169         // public synchronized void flowCompleted() {
 170         // // notifyAll();
 171         // }
 172
 173         public ExecutionProcess getProcess() {
 174                 return process;
 175         }
 176
 177         public ProcessThreadGroup getProcessThreadGroup() {
 178                 return processThreadGroup;
 179         }
 180
 181         public ExecutionModulesManager getExecutionModulesManager() {
 182                 return executionModulesManager;
 183         }
 184
 185         private class LoggingThread extends Thread {
 186
 187                 public LoggingThread() {
 188                         super("SLC Process Logger #" + process.getUuid());
 189                 }
 190
 191                 public void run() {
 192                         boolean run = true;
 193                         while (run) {
 194                                 List<ExecutionStep> newSteps = new ArrayList<ExecutionStep>();
 195                                 processThreadGroup.getSteps().drainTo(newSteps);
 196                                 if (newSteps.size() > 0) {
 197                                         // System.out.println(steps.size() + " steps");
 198                                         process.addSteps(newSteps);
 199                                 }
 200
 201                                 try {
 202                                         Thread.sleep(1000);
 203                                 } catch (InterruptedException e) {
 204                                         break;
 205                                 }
 206
 207                                 if (!ProcessThread.this.isAlive()
 208                                                 && processThreadGroup.getSteps().size() == 0)
 209                                         run = false;
 210                         }
 211                 }
 212
 213         }
 214 }