src/main/java/org/onap/music/lockingservice/MusicLockingService.java

   1 /*
   2  * ============LICENSE_START========================================== org.onap.music
   3  * =================================================================== Copyright (c) 2017 AT&T
   4  * Intellectual Property ===================================================================
   5  * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
   6  * in compliance with the License. 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 distributed under the License
  11  * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
  12  * or implied. See the License for the specific language governing permissions and limitations under
  13  * the License.
  14  *
  15  * ============LICENSE_END=============================================
  16  * ====================================================================
  17  */
  18 package org.onap.music.lockingservice;
  19
  20
  21 import java.io.IOException;
  22 import java.util.StringTokenizer;
  23 import java.util.concurrent.CountDownLatch;
  24
  25 import org.apache.zookeeper.KeeperException;
  26 import org.apache.zookeeper.WatchedEvent;
  27 import org.apache.zookeeper.Watcher;
  28 import org.apache.zookeeper.Watcher.Event.KeeperState;
  29 import org.apache.zookeeper.ZooKeeper;
  30 import org.onap.music.eelf.logging.EELFLoggerDelegate;
  31 import org.onap.music.eelf.logging.format.AppMessages;
  32 import org.onap.music.eelf.logging.format.ErrorSeverity;
  33 import org.onap.music.eelf.logging.format.ErrorTypes;
  34 import org.onap.music.exceptions.MusicLockingException;
  35 import org.onap.music.exceptions.MusicServiceException;
  36 import org.onap.music.main.MusicUtil;
  37
  38
  39 public class MusicLockingService implements Watcher {
  40
  41
  42     private static final int SESSION_TIMEOUT = 180000;
  43     ZkStatelessLockService zkLockHandle = null;
  44     private CountDownLatch connectedSignal = new CountDownLatch(1);
  45     private static EELFLoggerDelegate logger =
  46                     EELFLoggerDelegate.getLogger(MusicLockingService.class);
  47
  48     public MusicLockingService() throws MusicServiceException {
  49         try {
  50             ZooKeeper zk = new ZooKeeper(MusicUtil.getMyZkHost(), SESSION_TIMEOUT, this);
  51             connectedSignal.await();
  52             zkLockHandle = new ZkStatelessLockService(zk);
  53         } catch (IOException e) {
  54             logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.IOERROR, ErrorSeverity.ERROR, ErrorTypes.CONNECTIONERROR);
  55             throw new MusicServiceException("IO Error has occured" + e.getMessage());
  56         } catch (InterruptedException e) {
  57                 logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.EXECUTIONINTERRUPTED, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
  58             throw new MusicServiceException("Exception Occured " + e.getMessage());
  59         }
  60     }
  61
  62     public ZkStatelessLockService getzkLockHandle() {
  63         return zkLockHandle;
  64     }
  65
  66     public MusicLockingService(String lockServer) {
  67         try {
  68             ZooKeeper zk = new ZooKeeper(lockServer, SESSION_TIMEOUT, this);
  69             connectedSignal.await();
  70             zkLockHandle = new ZkStatelessLockService(zk);
  71         } catch (IOException e) {
  72                 logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.IOERROR, ErrorSeverity.ERROR, ErrorTypes.CONNECTIONERROR);
  73         }catch( InterruptedException e) {
  74                 logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.EXECUTIONINTERRUPTED, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
  75                 }catch(Exception e) {
  76                         logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.UNKNOWNERROR, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
  77                 }
  78     }
  79
  80     public void createLockaIfItDoesNotExist(String lockName) {
  81         if (!zkLockHandle.checkIfLockExists(lockName)) {
  82             String lockHolder = null;
  83             MusicLockState ml = new MusicLockState(MusicLockState.LockStatus.UNLOCKED, lockHolder);
  84             byte[] data = ml.serialize();
  85             zkLockHandle.createLock(lockName, data);
  86         }
  87     }
  88
  89     public void setLockState(String lockName, MusicLockState mls) {
  90         byte[] data = mls.serialize();
  91         zkLockHandle.setNodeData(lockName, data);
  92     }
  93
  94     public MusicLockState getLockState(String lockName) throws MusicLockingException {
  95
  96         byte[] data = null;
  97         try{
  98                 data = zkLockHandle.getNodeData(lockName);
  99         }catch (Exception ex){
 100                 logger.error(EELFLoggerDelegate.errorLogger, ex.getMessage(),AppMessages.UNKNOWNERROR, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
 101         }
 102         if(data !=null)
 103         return MusicLockState.deSerialize(data);
 104         else {
 105                 logger.error(EELFLoggerDelegate.errorLogger,"",AppMessages.INVALIDLOCK, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
 106                 throw new  MusicLockingException("Invalid lock or acquire failed");
 107         }
 108     }
 109
 110     public String createLockId(String lockName) {
 111         String lockIdWithSlash = zkLockHandle.createLockId(lockName);
 112         return lockIdWithSlash.replace('/', '$');
 113     }
 114
 115     public boolean isMyTurn(String lockIdWithDollar) {
 116         String lockId = lockIdWithDollar.replace('$', '/');
 117         StringTokenizer st = new StringTokenizer(lockId);
 118         String lockName = "/" + st.nextToken("/");
 119         try {
 120             return zkLockHandle.lock(lockName, lockId);
 121         } catch (KeeperException e) {
 122                 logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.LOCKINGERROR, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
 123         }catch( InterruptedException e) {
 124                 logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.EXECUTIONINTERRUPTED, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
 125                 }catch(Exception e) {
 126                         logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.UNKNOWNERROR, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
 127                 }
 128         return false;
 129     }
 130
 131     public void unlockAndDeleteId(String lockIdWithDollar) throws KeeperException.NoNodeException {
 132         String lockId = lockIdWithDollar.replace('$', '/');
 133         zkLockHandle.unlock(lockId);
 134     }
 135
 136     public void deleteLock(String lockName) {
 137         zkLockHandle.deleteLock(lockName);
 138     }
 139
 140     public String whoseTurnIsIt(String lockName) {
 141         String lockHolder = zkLockHandle.currentLockHolder(lockName);
 142         return lockHolder.replace('/', '$');
 143
 144     }
 145
 146     public void process(WatchedEvent event) { // Watcher interface
 147         if (event.getState() == KeeperState.SyncConnected) {
 148             connectedSignal.countDown();
 149         }
 150     }
 151
 152
 153     public void close() {
 154         zkLockHandle.close();
 155     }
 156
 157         public boolean lockIdExists(String lockIdWithDollar) {
 158                 String lockId = lockIdWithDollar.replace('$', '/');
 159                 return zkLockHandle.checkIfLockExists(lockId);
 160         }
 161
 162 }