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.CachingUtil;
  37 import org.onap.music.main.MusicUtil;
  38
  39
  40 public class MusicLockingService implements Watcher {
  41
  42
  43     private static final int SESSION_TIMEOUT = 180000;
  44     ZkStatelessLockService zkLockHandle = null;
  45     private CountDownLatch connectedSignal = new CountDownLatch(1);
  46     private static EELFLoggerDelegate logger =
  47                     EELFLoggerDelegate.getLogger(MusicLockingService.class);
  48
  49     public MusicLockingService() throws MusicServiceException {
  50         try {
  51             ZooKeeper zk = new ZooKeeper(MusicUtil.getMyZkHost(), SESSION_TIMEOUT, this);
  52             connectedSignal.await();
  53             zkLockHandle = new ZkStatelessLockService(zk);
  54         } catch (IOException e) {
  55             logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.IOERROR, ErrorSeverity.ERROR, ErrorTypes.CONNECTIONERROR);
  56             throw new MusicServiceException("IO Error has occured" + e.getMessage());
  57         } catch (InterruptedException e) {
  58                 logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.EXECUTIONINTERRUPTED, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
  59             throw new MusicServiceException("Exception Occured " + e.getMessage());
  60         }
  61     }
  62
  63     public ZkStatelessLockService getzkLockHandle() {
  64         return zkLockHandle;
  65     }
  66
  67     public MusicLockingService(String lockServer) {
  68         try {
  69             ZooKeeper zk = new ZooKeeper(lockServer, SESSION_TIMEOUT, this);
  70             connectedSignal.await();
  71             zkLockHandle = new ZkStatelessLockService(zk);
  72         } catch (IOException e) {
  73                 logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.IOERROR, ErrorSeverity.ERROR, ErrorTypes.CONNECTIONERROR);
  74         }catch( InterruptedException e) {
  75                 logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.EXECUTIONINTERRUPTED, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
  76                 }catch(Exception e) {
  77                         logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.UNKNOWNERROR, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
  78                 }
  79     }
  80
  81     public void createLockaIfItDoesNotExist(String lockName) {
  82         if (!zkLockHandle.checkIfLockExists(lockName)) {
  83             String lockHolder = null;
  84             MusicLockState ml = new MusicLockState(MusicLockState.LockStatus.UNLOCKED, lockHolder);
  85             byte[] data = ml.serialize();
  86             zkLockHandle.createLock(lockName, data);
  87         }
  88     }
  89
  90     public void setLockState(String lockName, MusicLockState mls) {
  91         byte[] data = mls.serialize();
  92         zkLockHandle.setNodeData(lockName, data);
  93     }
  94
  95     public MusicLockState getLockState(String lockName) throws MusicLockingException {
  96
  97         byte[] data = null;
  98         try{
  99                 data = zkLockHandle.getNodeData(lockName);
 100         }catch (Exception ex){
 101                 logger.error(EELFLoggerDelegate.errorLogger, ex.getMessage(),AppMessages.UNKNOWNERROR, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
 102         }
 103         if(data !=null)
 104         return MusicLockState.deSerialize(data);
 105         else {
 106                 logger.error(EELFLoggerDelegate.errorLogger,"",AppMessages.INVALIDLOCK, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
 107                 throw new  MusicLockingException("Invalid lock or acquire failed");
 108         }
 109     }
 110
 111     public String createLockId(String lockName) {
 112         String lockIdWithSlash = zkLockHandle.createLockId(lockName);
 113         return lockIdWithSlash.replace('/', '$');
 114     }
 115
 116     public boolean isMyTurn(String lockIdWithDollar) {
 117         String lockId = lockIdWithDollar.replace('$', '/');
 118         StringTokenizer st = new StringTokenizer(lockId);
 119         String lockName = "/" + st.nextToken("/");
 120         try {
 121             return zkLockHandle.lock(lockName, lockId);
 122         } catch (KeeperException e) {
 123                 logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.LOCKINGERROR, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
 124         }catch( InterruptedException e) {
 125                 logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.EXECUTIONINTERRUPTED, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
 126                 }catch(Exception e) {
 127                         logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.UNKNOWNERROR, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
 128                 }
 129         return false;
 130     }
 131
 132     public void unlockAndDeleteId(String lockIdWithDollar) throws KeeperException.NoNodeException {
 133         String lockId = lockIdWithDollar.replace('$', '/');
 134         zkLockHandle.unlock(lockId);
 135         CachingUtil.deleteKeysFromDB("'"+lockId+"'");
 136     }
 137
 138     public void deleteLock(String lockName) throws MusicLockingException {
 139         if(lockIdExists(lockName))
 140                 zkLockHandle.deleteLock(lockName);
 141         else{
 142                 throw new MusicLockingException("Lock does not exist.Please check the lock: " + lockName + " and try again");
 143         }
 144     }
 145
 146     public String whoseTurnIsIt(String lockName) {
 147         String lockHolder = zkLockHandle.currentLockHolder(lockName);
 148         return lockHolder.replace('/', '$');
 149
 150     }
 151
 152     public void process(WatchedEvent event) { // Watcher interface
 153         if (event.getState() == KeeperState.SyncConnected) {
 154             connectedSignal.countDown();
 155         }
 156     }
 157
 158
 159     public void close() {
 160         zkLockHandle.close();
 161     }
 162
 163         public boolean lockIdExists(String lockIdWithDollar) {
 164                 String lockId = lockIdWithDollar.replace('$', '/');
 165                 return zkLockHandle.checkIfLockExists(lockId);
 166         }
 167
 168 }