runtime/org.argeo.slc.core/src/main/java/org/argeo/slc/core/execution/ExecutionThread.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.List;
  20
  21 import org.apache.commons.logging.Log;
  22 import org.apache.commons.logging.LogFactory;
  23 import org.argeo.slc.SlcException;
  24 import org.argeo.slc.execution.ExecutionFlowDescriptor;
  25 import org.argeo.slc.execution.ExecutionStep;
  26 import org.argeo.slc.execution.RealizedFlow;
  27 import org.springframework.security.Authentication;
  28 import org.springframework.security.context.SecurityContextHolder;
  29
  30 /** Thread of a single execution */
  31 public class ExecutionThread extends Thread {
  32         public final static String SYSPROP_EXECUTION_AUTO_UPGRADE = "slc.execution.autoupgrade";
  33
  34         private final static Log log = LogFactory.getLog(ExecutionThread.class);
  35
  36         private final RealizedFlow realizedFlow;
  37         private final ProcessThread processThread;
  38
  39         private List<Runnable> destructionCallbacks = new ArrayList<Runnable>();
  40
  41         public ExecutionThread(ProcessThread processThread,
  42                         RealizedFlow realizedFlow) {
  43                 super(processThread.getProcessThreadGroup(), "Flow "
  44                                 + realizedFlow.getFlowDescriptor().getName());
  45                 this.realizedFlow = realizedFlow;
  46                 this.processThread = processThread;
  47         }
  48
  49         public void run() {
  50                 // authenticate thread
  51                 Authentication authentication = getProcessThreadGroup()
  52                                 .getAuthentication();
  53                 if (authentication == null)
  54                         throw new SlcException("Can only execute authenticated threads");
  55                 SecurityContextHolder.getContext().setAuthentication(authentication);
  56
  57                 // Retrieve execution flow descriptor
  58                 ExecutionFlowDescriptor executionFlowDescriptor = realizedFlow
  59                                 .getFlowDescriptor();
  60                 String flowName = executionFlowDescriptor.getName();
  61
  62                 dispatchAddStep(new ExecutionStep(realizedFlow.getModuleName(),
  63                                 ExecutionStep.PHASE_START, "Flow " + flowName));
  64
  65                 try {
  66                         String autoUpgrade = System
  67                                         .getProperty(SYSPROP_EXECUTION_AUTO_UPGRADE);
  68                         if (autoUpgrade != null && autoUpgrade.equals("true"))
  69                                 processThread.getExecutionModulesManager().upgrade(
  70                                                 realizedFlow.getModuleNameVersion());
  71
  72                         // START FLOW
  73                         processThread.getExecutionModulesManager().execute(realizedFlow);
  74                         // END FLOW
  75                 } catch (Exception e) {
  76                         // TODO: re-throw exception ?
  77                         String msg = "Execution of flow " + flowName + " failed.";
  78                         log.error(msg, e);
  79                         dispatchAddStep(new ExecutionStep(realizedFlow.getModuleName(),
  80                                         ExecutionStep.ERROR, msg + " " + e.getMessage()));
  81                         processThread.notifyError();
  82                 } finally {
  83                         processThread.flowCompleted();
  84                         dispatchAddStep(new ExecutionStep(realizedFlow.getModuleName(),
  85                                         ExecutionStep.PHASE_END, "Flow " + flowName));
  86                         processDestructionCallbacks();
  87                 }
  88         }
  89
  90         private void dispatchAddStep(ExecutionStep step) {
  91                 processThread.getProcessThreadGroup().dispatchAddStep(step);
  92         }
  93
  94         private synchronized void processDestructionCallbacks() {
  95                 for (int i = destructionCallbacks.size() - 1; i >= 0; i--) {
  96                         try {
  97                                 destructionCallbacks.get(i).run();
  98                         } catch (Exception e) {
  99                                 log.warn("Could not process destruction callback " + i
 100                                                 + " in thread " + getName(), e);
 101                         }
 102                 }
 103         }
 104
 105         /**
 106          * Gather object destruction callback to be called in reverse order at the
 107          * end of the thread
 108          */
 109         synchronized void registerDestructionCallback(String name, Runnable callback) {
 110                 destructionCallbacks.add(callback);
 111         }
 112
 113         protected ProcessThreadGroup getProcessThreadGroup() {
 114                 return processThread.getProcessThreadGroup();
 115         }
 116
 117         public RealizedFlow getRealizedFlow() {
 118                 return realizedFlow;
 119         }
 120
 121 }