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("Error", e);
  56             logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.IOERROR, ErrorSeverity.ERROR, ErrorTypes.CONNECTIONERROR);
  57             throw new MusicServiceException("IO Error has occured" + e.getMessage());
  58         } catch (InterruptedException e) {
  59             logger.error("Error", e);
  60                 logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.EXECUTIONINTERRUPTED, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
  61             throw new MusicServiceException("Exception Occured " + e.getMessage());
  62         }
  63     }
  64
  65     public MusicLockingService(String lockServer) {
  66         try {
  67             ZooKeeper zk = new ZooKeeper(lockServer, SESSION_TIMEOUT, this);
  68             connectedSignal.await();
  69             zkLockHandle = new ZkStatelessLockService(zk);
  70         } catch (IOException e) {
  71             logger.error("Error", e);
  72             logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.IOERROR, ErrorSeverity.ERROR, ErrorTypes.CONNECTIONERROR);
  73         }catch( InterruptedException e) {
  74             logger.error("Error", e);
  75             logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.EXECUTIONINTERRUPTED, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
  76         }catch(Exception e) {
  77             logger.error("Error", e);
  78             logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.UNKNOWNERROR, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
  79         }
  80     }
  81
  82     public ZkStatelessLockService getzkLockHandle() {
  83         return zkLockHandle;
  84     }
  85
  86     public void createLockaIfItDoesNotExist(String lockName) {
  87         if (!zkLockHandle.checkIfLockExists(lockName)) {
  88             String lockHolder = null;
  89             MusicLockState ml = new MusicLockState(MusicLockState.LockStatus.UNLOCKED, lockHolder);
  90             byte[] data = ml.serialize();
  91             zkLockHandle.createLock(lockName, data);
  92         }
  93     }
  94
  95     public void setLockState(String lockName, MusicLockState mls) {
  96         byte[] data = mls.serialize();
  97         zkLockHandle.setNodeData(lockName, data);
  98     }
  99
 100     public MusicLockState getLockState(String lockName) throws MusicLockingException {
 101
 102         byte[] data = null;
 103         try{
 104                 data = zkLockHandle.getNodeData(lockName);
 105         }catch (Exception ex){
 106                 logger.error(EELFLoggerDelegate.errorLogger, ex,AppMessages.UNKNOWNERROR, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
 107         }
 108         if(data !=null)
 109         return MusicLockState.deSerialize(data);
 110         else {
 111                 logger.error(EELFLoggerDelegate.errorLogger,"",AppMessages.INVALIDLOCK, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
 112                 throw new  MusicLockingException("Invalid lock or acquire failed");
 113         }
 114     }
 115
 116     public String createLockId(String lockName) {
 117         String lockIdWithSlash = zkLockHandle.createLockId(lockName);
 118         return lockIdWithSlash.replace('/', '$');
 119     }
 120
 121     public boolean isMyTurn(String lockIdWithDollar) {
 122         String lockId = lockIdWithDollar.replace('$', '/');
 123         StringTokenizer st = new StringTokenizer(lockId);
 124         String lockName = "/" + st.nextToken("/");
 125         try {
 126             return zkLockHandle.lock(lockName, lockId);
 127         } catch (KeeperException e) {
 128             logger.error("Error", e);
 129                 logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.LOCKINGERROR, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
 130         }catch( InterruptedException e) {
 131             logger.error("Error", e);
 132                 logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.EXECUTIONINTERRUPTED, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
 133                 }catch(Exception e) {
 134             logger.error("Error", e);
 135                         logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.UNKNOWNERROR, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
 136                 }
 137         return false;
 138     }
 139
 140     public void unlockAndDeleteId(String lockIdWithDollar) throws KeeperException.NoNodeException {
 141         String lockId = lockIdWithDollar.replace('$', '/');
 142         zkLockHandle.unlock(lockId);
 143         CachingUtil.deleteKeysFromDB("'"+lockId+"'");
 144     }
 145
 146     public void deleteLock(String lockName) throws MusicLockingException {
 147         if(lockIdExists(lockName))
 148                 zkLockHandle.deleteLock(lockName);
 149         else{
 150                 throw new MusicLockingException("Lock does not exist.Please check the lock: " + lockName + " and try again");
 151         }
 152     }
 153
 154     public String whoseTurnIsIt(String lockName) {
 155         String lockHolder = zkLockHandle.currentLockHolder(lockName);
 156         return lockHolder.replace('/', '$');
 157
 158     }
 159
 160     public void process(WatchedEvent event) { // Watcher interface
 161         if (event.getState() == KeeperState.SyncConnected) {
 162             connectedSignal.countDown();
 163         }
 164     }
 165
 166
 167     public void close() {
 168         zkLockHandle.close();
 169     }
 170
 171         public boolean lockIdExists(String lockIdWithDollar) {
 172                 String lockId = lockIdWithDollar.replace('$', '/');
 173                 return zkLockHandle.checkIfLockExists(lockId);
 174         }
 175
 176 }