bpmn/mso-infrastructure-bpmn/src/main/java/org/onap/so/bpmn/core/plugins/WorkflowExceptionPlugin.java

   1 /*-
   2  * ============LICENSE_START=======================================================
   3  * ONAP - SO
   4  * ================================================================================
   5  * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
   6  * ================================================================================
   7  * Modifications Copyright (c) 2019 Samsung
   8  * ================================================================================
   9  * Licensed under the Apache License, Version 2.0 (the "License");
  10  * you may not use this file except in compliance with the License.
  11  * You may obtain a copy of the License at
  12  *
  13  *      http://www.apache.org/licenses/LICENSE-2.0
  14  *
  15  * Unless required by applicable law or agreed to in writing, software
  16  * distributed under the License is distributed on an "AS IS" BASIS,
  17  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  18  * See the License for the specific language governing permissions and
  19  * limitations under the License.
  20  * ============LICENSE_END=========================================================
  21  */
  22
  23 package org.onap.so.bpmn.core.plugins;
  24
  25 import java.util.ArrayList;
  26 import java.util.List;
  27 import java.util.concurrent.atomic.AtomicInteger;
  28 import org.camunda.bpm.engine.delegate.BpmnError;
  29 import org.camunda.bpm.engine.delegate.DelegateExecution;
  30 import org.camunda.bpm.engine.delegate.ExecutionListener;
  31 import org.camunda.bpm.engine.delegate.JavaDelegate;
  32 import org.camunda.bpm.engine.impl.bpmn.behavior.ClassDelegateActivityBehavior;
  33 import org.camunda.bpm.engine.impl.bpmn.parser.AbstractBpmnParseListener;
  34 import org.camunda.bpm.engine.impl.bpmn.parser.BpmnParseListener;
  35 import org.camunda.bpm.engine.impl.cfg.AbstractProcessEnginePlugin;
  36 import org.camunda.bpm.engine.impl.cfg.ProcessEngineConfigurationImpl;
  37 import org.camunda.bpm.engine.impl.persistence.entity.ProcessDefinitionEntity;
  38 import org.camunda.bpm.engine.impl.pvm.PvmTransition;
  39 import org.camunda.bpm.engine.impl.pvm.process.ActivityImpl;
  40 import org.camunda.bpm.engine.impl.pvm.process.TransitionImpl;
  41 import org.camunda.bpm.engine.impl.util.xml.Element;
  42 import org.onap.so.bpmn.core.WorkflowException;
  43 import org.springframework.stereotype.Component;
  44 import org.slf4j.Logger;
  45 import org.slf4j.LoggerFactory;
  46
  47 /**
  48  * This plugin does the following:
  49  * <ol>
  50  * <li>Adds logic at the start of every Call Activity to remove any existing WorkflowException object from the execution
  51  * (saving a copy of it in a different variable).</li>
  52  * <li>Adds logic at the end of every Call Activity to generate a MSOWorkflowException event if there is a
  53  * WorkflowException object in the execution.</li>
  54  * </ol>
  55  */
  56 @Component
  57 public class WorkflowExceptionPlugin extends AbstractProcessEnginePlugin {
  58     private static final Logger logger = LoggerFactory.getLogger(WorkflowExceptionPlugin.class);
  59
  60     private static final String WORKFLOW_EXCEPTION = "WorkflowException";
  61     private static final String PAUSE_FOR_MANUAL_TASK_RAINY_DAY_ID = "PauseForManualTaskRainyDay";
  62
  63     @Override
  64     public void preInit(ProcessEngineConfigurationImpl processEngineConfiguration) {
  65         List<BpmnParseListener> preParseListeners = processEngineConfiguration.getCustomPreBPMNParseListeners();
  66
  67         if (preParseListeners == null) {
  68             preParseListeners = new ArrayList<>();
  69             processEngineConfiguration.setCustomPreBPMNParseListeners(preParseListeners);
  70         }
  71
  72         preParseListeners.add(new WorkflowExceptionParseListener());
  73     }
  74
  75     public static class WorkflowExceptionParseListener extends AbstractBpmnParseListener {
  76         @Override
  77         public void parseProcess(Element processElement, ProcessDefinitionEntity processDefinition) {
  78             AtomicInteger triggerTaskIndex = new AtomicInteger(1);
  79             List<ActivityImpl> activities = new ArrayList<>(processDefinition.getActivities());
  80             recurse(activities, triggerTaskIndex);
  81         }
  82
  83         /**
  84          * Helper method that recurses (into subprocesses) over all the listed activities.
  85          *
  86          * @param activities a list of workflow activities
  87          * @param triggerTaskIndex the index of the next trigger task (mutable)
  88          */
  89         private void recurse(List<ActivityImpl> activities, AtomicInteger triggerTaskIndex) {
  90             for (ActivityImpl activity : activities) {
  91                 String type = (String) activity.getProperty("type");
  92
  93                 if ("callActivity".equals(type)
  94                         && !PAUSE_FOR_MANUAL_TASK_RAINY_DAY_ID.equals(activity.getActivityId())) {
  95                     // Add a WorkflowExceptionResetListener to clear the WorkflowException
  96                     // variable when each Call Activity starts.
  97
  98                     activity.addListener(ExecutionListener.EVENTNAME_START, new WorkflowExceptionResetListener());
  99
 100                     // Add a WorkflowExceptionTriggerTask after the call activity.
 101                     // It must be a task because a listener cannot be used to generate
 102                     // an event. Throwing BpmnError from an execution listener will
 103                     // cause the process to die.
 104
 105                     List<PvmTransition> outTransitions = new ArrayList<>(activity.getOutgoingTransitions());
 106
 107                     for (PvmTransition transition : outTransitions) {
 108                         String triggerTaskId = "WorkflowExceptionTriggerTask_" + triggerTaskIndex;
 109
 110                         ActivityImpl triggerTask = activity.getFlowScope().createActivity(triggerTaskId);
 111
 112                         ClassDelegateActivityBehavior behavior = new ClassDelegateActivityBehavior(
 113                                 WorkflowExceptionTriggerTask.class.getName(), new ArrayList<>(0));
 114
 115                         triggerTask.setActivityBehavior(behavior);
 116                         triggerTask.setName("Workflow Exception Trigger Task " + triggerTaskIndex);
 117                         triggerTaskIndex.getAndIncrement();
 118
 119                         TransitionImpl transitionImpl = (TransitionImpl) transition;
 120                         TransitionImpl triggerTaskOutTransition = triggerTask.createOutgoingTransition();
 121                         triggerTaskOutTransition.setDestination((ActivityImpl) transitionImpl.getDestination());
 122                         transitionImpl.setDestination(triggerTask);
 123                     }
 124                 } else if ("subProcess".equals(type)) {
 125                     recurse(new ArrayList<>(activity.getActivities()), triggerTaskIndex);
 126                 }
 127             }
 128         }
 129     }
 130
 131     /**
 132      * If there is a WorkflowException object in the execution, this method removes it (saving a copy of it in a
 133      * different variable).
 134      */
 135     public static class WorkflowExceptionResetListener implements ExecutionListener {
 136         public void notify(DelegateExecution execution) throws Exception {
 137             Object workflowException = execution.getVariable(WORKFLOW_EXCEPTION);
 138
 139             if (workflowException instanceof WorkflowException) {
 140                 int index = 1;
 141                 String saveName = "SavedWorkflowException" + index;
 142                 while (execution.getVariable(saveName) != null) {
 143                     saveName = "SavedWorkflowException" + (++index);
 144                 }
 145
 146                 logger.debug("WorkflowExceptionResetTask is moving WorkflowException to {}", saveName);
 147
 148                 execution.setVariable(saveName, workflowException);
 149                 execution.setVariable(WORKFLOW_EXCEPTION, null);
 150             }
 151         }
 152     }
 153
 154     /**
 155      * Generates an MSOWorkflowException event if there is a WorkflowException object in the execution.
 156      */
 157     public static class WorkflowExceptionTriggerTask implements JavaDelegate {
 158         public void execute(DelegateExecution execution) throws Exception {
 159             if (execution.getVariable(WORKFLOW_EXCEPTION) instanceof WorkflowException) {
 160                 logger.debug("WorkflowExceptionTriggerTask is generating a MSOWorkflowException event");
 161                 throw new BpmnError("MSOWorkflowException");
 162             }
 163         }
 164     }
 165 }