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
  29 import org.camunda.bpm.engine.delegate.BpmnError;
  30 import org.camunda.bpm.engine.delegate.DelegateExecution;
  31 import org.camunda.bpm.engine.delegate.ExecutionListener;
  32 import org.camunda.bpm.engine.delegate.JavaDelegate;
  33 import org.camunda.bpm.engine.impl.bpmn.behavior.ClassDelegateActivityBehavior;
  34 import org.camunda.bpm.engine.impl.bpmn.parser.AbstractBpmnParseListener;
  35 import org.camunda.bpm.engine.impl.bpmn.parser.BpmnParseListener;
  36 import org.camunda.bpm.engine.impl.bpmn.parser.FieldDeclaration;
  37 import org.camunda.bpm.engine.impl.cfg.AbstractProcessEnginePlugin;
  38 import org.camunda.bpm.engine.impl.cfg.ProcessEngineConfigurationImpl;
  39 import org.camunda.bpm.engine.impl.persistence.entity.ProcessDefinitionEntity;
  40 import org.camunda.bpm.engine.impl.pvm.PvmTransition;
  41 import org.camunda.bpm.engine.impl.pvm.process.ActivityImpl;
  42 import org.camunda.bpm.engine.impl.pvm.process.TransitionImpl;
  43 import org.camunda.bpm.engine.impl.util.xml.Element;
  44
  45 import org.onap.so.bpmn.core.WorkflowException;
  46 import org.springframework.stereotype.Component;
  47 import org.slf4j.Logger;
  48 import org.slf4j.LoggerFactory;
  49
  50 /**
  51  * This plugin does the following:
  52  * <ol>
  53  * <li>
  54  * Adds logic at the start of every Call Activity to remove any existing
  55  * WorkflowException object from the execution (saving a copy of it in a
  56  * different variable).
  57  * </li>
  58  * <li>
  59  * Adds logic at the end of every Call Activity to generate a MSOWorkflowException
  60  * event if there is a WorkflowException object in the execution.
  61  * </li>
  62  * </ol>
  63  */
  64 @Component
  65 public class WorkflowExceptionPlugin extends AbstractProcessEnginePlugin {
  66         private static final Logger logger = LoggerFactory.getLogger(WorkflowExceptionPlugin.class);
  67
  68         @Override
  69         public void preInit(ProcessEngineConfigurationImpl processEngineConfiguration) {
  70                 List<BpmnParseListener> preParseListeners =
  71                         processEngineConfiguration.getCustomPreBPMNParseListeners();
  72
  73                 if (preParseListeners == null) {
  74                         preParseListeners = new ArrayList<>();
  75                         processEngineConfiguration.setCustomPreBPMNParseListeners(preParseListeners);
  76                 }
  77
  78                 preParseListeners.add(new WorkflowExceptionParseListener());
  79         }
  80
  81         public static class WorkflowExceptionParseListener extends AbstractBpmnParseListener {
  82                 @Override
  83                 public void parseProcess(Element processElement, ProcessDefinitionEntity processDefinition) {
  84                         AtomicInteger triggerTaskIndex = new AtomicInteger(1);
  85                         List<ActivityImpl> activities = new ArrayList<>(processDefinition.getActivities());
  86                         recurse(activities, triggerTaskIndex);
  87                 }
  88
  89                 /**
  90                  * Helper method that recurses (into subprocesses) over all the listed activities.
  91                  * @param activities a list of workflow activities
  92                  * @param triggerTaskIndex the index of the next trigger task (mutable)
  93                  */
  94                 private void recurse(List<ActivityImpl> activities, AtomicInteger triggerTaskIndex) {
  95                         for (ActivityImpl activity : activities) {
  96                                 String type = (String) activity.getProperty("type");
  97
  98                                 if ("callActivity".equals(type)) {
  99                                         // Add a WorkflowExceptionResetListener to clear the WorkflowException
 100                                         // variable when each Call Activity starts.
 101
 102                                         activity.addListener(
 103                                                 ExecutionListener.EVENTNAME_START,
 104                                                 new WorkflowExceptionResetListener());
 105
 106                                         // Add a WorkflowExceptionTriggerTask after the call activity.
 107                                         // It must be a task because a listener cannot be used to generate
 108                                         // an event.  Throwing BpmnError from an execution listener will
 109                                         // cause the process to die.
 110
 111                                         List<PvmTransition> outTransitions =
 112                         new ArrayList<>(activity.getOutgoingTransitions());
 113
 114                                         for (PvmTransition transition : outTransitions) {
 115                                                 String triggerTaskId = "WorkflowExceptionTriggerTask_" + triggerTaskIndex;
 116
 117                                                 ActivityImpl triggerTask = activity.getFlowScope().createActivity(triggerTaskId);
 118
 119                                                 ClassDelegateActivityBehavior behavior = new  ClassDelegateActivityBehavior(
 120                                                                 WorkflowExceptionTriggerTask.class.getName(),
 121                             new ArrayList<>(0));
 122
 123                                                 triggerTask.setActivityBehavior(behavior);
 124                                                 triggerTask.setName("Workflow Exception Trigger Task " + triggerTaskIndex);
 125                                                 triggerTaskIndex.getAndIncrement();
 126
 127                                                 TransitionImpl transitionImpl = (TransitionImpl) transition;
 128                                                 TransitionImpl triggerTaskOutTransition = triggerTask.createOutgoingTransition();
 129                                                 triggerTaskOutTransition.setDestination((ActivityImpl)transitionImpl.getDestination());
 130                                                 transitionImpl.setDestination(triggerTask);
 131                                         }
 132                                 } else if ("subProcess".equals(type)) {
 133                                         recurse(new ArrayList<>(activity.getActivities()), triggerTaskIndex);
 134                                 }
 135                         }
 136                 }
 137         }
 138
 139     /**
 140      * If there is a WorkflowException object in the execution, this method
 141      * removes it (saving a copy of it in a different variable).
 142      */
 143         public static class WorkflowExceptionResetListener implements ExecutionListener {
 144                 public void notify(DelegateExecution execution) throws Exception {
 145                         Object workflowException = execution.getVariable("WorkflowException");
 146
 147                         if (workflowException instanceof WorkflowException) {
 148                                 int index = 1;
 149                                 String saveName = "SavedWorkflowException" + index;
 150                                 while (execution.getVariable(saveName) != null) {
 151                                         saveName = "SavedWorkflowException" + (++index);
 152                                 }
 153
 154                                 logger.debug("WorkflowExceptionResetTask is moving WorkflowException to " + saveName);
 155
 156                                 execution.setVariable(saveName, workflowException);
 157                                 execution.setVariable("WorkflowException", null);
 158                         }
 159                 }
 160         }
 161
 162     /**
 163      * Generates an MSOWorkflowException event if there is a WorkflowException
 164      * object in the execution.
 165      */
 166         public static class WorkflowExceptionTriggerTask implements JavaDelegate {
 167                 public void execute(DelegateExecution execution) throws Exception {
 168                         if (execution.getVariable("WorkflowException") instanceof WorkflowException) {
 169                                 logger.debug("WorkflowExceptionTriggerTask is generating a MSOWorkflowException event");
 170                                 throw new BpmnError("MSOWorkflowException");
 171                         }
 172                 }
 173         }
 174 }