bpmn/MSOCommonBPMN/src/main/java/org/onap/so/bpmn/common/workflow/context/WorkflowContextHolder.java

   1 package org.onap.so.bpmn.common.workflow.context;
   2 /*-
   3  * ============LICENSE_START=======================================================
   4  * ONAP - SO
   5  * ================================================================================
   6  * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
   7  * ================================================================================
   8  * Licensed under the Apache License, Version 2.0 (the "License");
   9  * you may not use this file except in compliance with the License.
  10  * You may obtain a copy of the License at
  11  *
  12  *      http://www.apache.org/licenses/LICENSE-2.0
  13  *
  14  * Unless required by applicable law or agreed to in writing, software
  15  * distributed under the License is distributed on an "AS IS" BASIS,
  16  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  17  * See the License for the specific language governing permissions and
  18  * limitations under the License.
  19  * ============LICENSE_END=========================================================
  20  */
  21
  22
  23
  24 import java.util.concurrent.DelayQueue;
  25 import java.util.concurrent.TimeUnit;
  26
  27 import org.onap.so.logger.MessageEnum;
  28 import org.onap.so.logger.MsoLogger;
  29 import org.springframework.stereotype.Component;
  30
  31 /**
  32  * Workflow Context Holder instance which can be accessed elsewhere either in groovy scripts or Java
  33  * @version 1.0
  34  *
  35  */
  36
  37 @Component
  38 public class WorkflowContextHolder {
  39
  40         private static MsoLogger msoLogger = MsoLogger.getMsoLogger(MsoLogger.Catalog.BPEL,WorkflowContextHolder.class);
  41         private static final String logMarker = "[WORKFLOW-CONTEXT-HOLDER]";
  42         private static WorkflowContextHolder instance = null;
  43
  44
  45         private long defaultContextTimeout=60000;
  46
  47         /**
  48          * Delay Queue which holds workflow context holder objects
  49          */
  50         private final DelayQueue<WorkflowContext> responseQueue = new DelayQueue<>();
  51         private final TimeoutThread timeoutThread = new TimeoutThread();
  52
  53         private WorkflowContextHolder() {
  54                 timeoutThread.start();
  55         }
  56
  57         /**
  58          * Singleton holder which eliminates hot lock
  59          * Since the JVM synchronizes static method there is no synchronization needed for this method
  60          * @return
  61          */
  62         public static synchronized WorkflowContextHolder getInstance() {
  63                 if (instance == null) {
  64                         instance = new WorkflowContextHolder();
  65                 }
  66                 return instance;
  67         }
  68
  69         public void put(WorkflowContext context) {
  70                 msoLogger.debug(logMarker + " Adding context to the queue: "
  71                         + context.getRequestId());
  72                 responseQueue.put(context);
  73         }
  74
  75         public void remove(WorkflowContext context) {
  76                 msoLogger.debug(logMarker + " Removing context from the queue: "
  77                         + context.getRequestId());
  78                 responseQueue.remove(context);
  79         }
  80
  81         public WorkflowContext getWorkflowContext(String requestId) {
  82                 // Note: DelayQueue interator is threadsafe
  83                 for (WorkflowContext context : responseQueue) {
  84                         if (requestId.equals(context.getRequestId())) {
  85                                 msoLogger.debug("Found context for request id: " + requestId);
  86                                 return context;
  87                         }
  88                 }
  89
  90                 msoLogger.debug("Unable to find context for request id: " + requestId);
  91                 return null;
  92         }
  93
  94         /**
  95          * Builds the callback response object to respond to client
  96          * @param processKey
  97          * @param processInstanceId
  98          * @param requestId
  99          * @param callbackResponse
 100          * @return
 101          */
 102         public void processCallback(String processKey, String processInstanceId,
 103                         String requestId, WorkflowCallbackResponse callbackResponse) {
 104                 WorkflowResponse workflowResponse = new WorkflowResponse();
 105                 workflowResponse.setResponse(callbackResponse.getResponse());
 106                 workflowResponse.setProcessInstanceID(processInstanceId);
 107                 workflowResponse.setMessageCode(callbackResponse.getStatusCode());
 108                 workflowResponse.setMessage(callbackResponse.getMessage());
 109                 WorkflowContext context = new WorkflowContext(processKey, requestId, defaultContextTimeout,workflowResponse);
 110                 put(context);
 111         }
 112
 113
 114         /**
 115          * Timeout thread which monitors the delay queue for expired context and send timeout response
 116          * to client
 117          *
 118          * */
 119         private class TimeoutThread extends Thread {
 120                 @Override
 121                 public void run() {
 122                         while (!isInterrupted()) {
 123                                 try {
 124                                         WorkflowContext requestObject = responseQueue.take();
 125                                         MsoLogger.setLogContext(requestObject.getRequestId(), null);
 126                                         msoLogger.debug("Time remaining for request id: " + requestObject.getRequestId() + ":" + requestObject.getDelay(TimeUnit.MILLISECONDS));
 127                                         msoLogger.debug("Preparing timeout response for " + requestObject.getProcessKey() + ":" + ":" + requestObject.getRequestId());
 128                                 } catch (InterruptedException e) {
 129                                         Thread.currentThread().interrupt();
 130                                 } catch (Exception e) {
 131                                         msoLogger.debug("WorkflowContextHolder timeout thread caught exception: " + e);
 132                                 msoLogger.error(MessageEnum.BPMN_GENERAL_EXCEPTION, "BPMN", MsoLogger.getServiceName(),
 133                                                 MsoLogger.ErrorCode.UnknownError, "Error in WorkflowContextHolder timeout thread");
 134
 135                                 }
 136                         }
 137                         msoLogger.debug("WorkflowContextHolder timeout thread interrupted, quitting");
 138                 }
 139         }
 140 }