Clarify SLC project structure.

[gpl/argeo-slc.git] / cms / org.argeo.slc.runtime / src / org / argeo / slc / runtime / ExecutionThread.java

diff --git a/cms/org.argeo.slc.runtime/src/org/argeo/slc/runtime/ExecutionThread.java b/cms/org.argeo.slc.runtime/src/org/argeo/slc/runtime/ExecutionThread.java
new file mode 100644 (file)
index 0000000..d940905
--- /dev/null
+++ b/cms/org.argeo.slc.runtime/src/org/argeo/slc/runtime/ExecutionThread.java
@@ -0,0 +1,116 @@
+package org.argeo.slc.runtime;
+
+import java.security.AccessControlContext;
+import java.security.AccessController;
+import java.security.PrivilegedActionException;
+import java.security.PrivilegedExceptionAction;
+import java.util.ArrayList;
+import java.util.List;
+
+import javax.security.auth.Subject;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.argeo.slc.execution.ExecutionFlowDescriptor;
+import org.argeo.slc.execution.ExecutionModulesManager;
+import org.argeo.slc.execution.ExecutionStep;
+import org.argeo.slc.execution.FlowConfigurationException;
+import org.argeo.slc.execution.RealizedFlow;
+
+/** Thread of a single execution */
+public class ExecutionThread extends Thread {
+       public final static String SYSPROP_EXECUTION_AUTO_UPGRADE = "slc.execution.autoupgrade";
+       private final static Log log = LogFactory.getLog(ExecutionThread.class);
+
+       private ExecutionModulesManager executionModulesManager;
+       private final RealizedFlow realizedFlow;
+       private final AccessControlContext accessControlContext;
+
+       private List<Runnable> destructionCallbacks = new ArrayList<Runnable>();
+
+       public ExecutionThread(ProcessThreadGroup processThreadGroup, ExecutionModulesManager executionModulesManager,
+                       RealizedFlow realizedFlow) {
+               super(processThreadGroup, "Flow " + realizedFlow.getFlowDescriptor().getName());
+               this.realizedFlow = realizedFlow;
+               this.executionModulesManager = executionModulesManager;
+               accessControlContext = AccessController.getContext();
+       }
+
+       public void run() {
+               // authenticate thread
+               // Authentication authentication = getProcessThreadGroup()
+               // .getAuthentication();
+               // if (authentication == null)
+               // throw new SlcException("Can only execute authenticated threads");
+               // SecurityContextHolder.getContext().setAuthentication(authentication);
+
+               // Retrieve execution flow descriptor
+               ExecutionFlowDescriptor executionFlowDescriptor = realizedFlow.getFlowDescriptor();
+               String flowName = executionFlowDescriptor.getName();
+
+               getProcessThreadGroup().dispatchAddStep(
+                               new ExecutionStep(realizedFlow.getModuleName(), ExecutionStep.PHASE_START, "Flow " + flowName));
+
+               try {
+                       Subject subject = Subject.getSubject(accessControlContext);
+                       try {
+                               Subject.doAs(subject, new PrivilegedExceptionAction<Void>() {
+
+                                       @Override
+                                       public Void run() throws Exception {
+                                               String autoUpgrade = System.getProperty(SYSPROP_EXECUTION_AUTO_UPGRADE);
+                                               if (autoUpgrade != null && autoUpgrade.equals("true"))
+                                                       executionModulesManager.upgrade(realizedFlow.getModuleNameVersion());
+                                               executionModulesManager.start(realizedFlow.getModuleNameVersion());
+                                               //
+                                               // START FLOW
+                                               //
+                                               executionModulesManager.execute(realizedFlow);
+                                               // END FLOW
+                                               return null;
+                                       }
+
+                               });
+                       } catch (PrivilegedActionException privilegedActionException) {
+                               throw (Exception) privilegedActionException.getCause();
+                       }
+               } catch (FlowConfigurationException e) {
+                       String msg = "Configuration problem with flow " + flowName + ":\n" + e.getMessage();
+                       log.error(msg);
+                       getProcessThreadGroup().dispatchAddStep(
+                                       new ExecutionStep(realizedFlow.getModuleName(), ExecutionStep.ERROR, msg + " " + e.getMessage()));
+               } catch (Exception e) {
+                       // TODO: re-throw exception ?
+                       String msg = "Execution of flow " + flowName + " failed.";
+                       log.error(msg, e);
+                       getProcessThreadGroup().dispatchAddStep(
+                                       new ExecutionStep(realizedFlow.getModuleName(), ExecutionStep.ERROR, msg + " " + e.getMessage()));
+               } finally {
+                       getProcessThreadGroup().dispatchAddStep(
+                                       new ExecutionStep(realizedFlow.getModuleName(), ExecutionStep.PHASE_END, "Flow " + flowName));
+                       processDestructionCallbacks();
+               }
+       }
+
+       private synchronized void processDestructionCallbacks() {
+               for (int i = destructionCallbacks.size() - 1; i >= 0; i--) {
+                       try {
+                               destructionCallbacks.get(i).run();
+                       } catch (Exception e) {
+                               log.warn("Could not process destruction callback " + i + " in thread " + getName(), e);
+                       }
+               }
+       }
+
+       /**
+        * Gather object destruction callback to be called in reverse order at the
+        * end of the thread
+        */
+       public synchronized void registerDestructionCallback(String name, Runnable callback) {
+               destructionCallbacks.add(callback);
+       }
+
+       protected ProcessThreadGroup getProcessThreadGroup() {
+               return (ProcessThreadGroup) getThreadGroup();
+       }
+}
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