Merge "Deadlock detection by owner"

diff --combined src/main/java/org/onap/music/lockingservice/cassandra/CassaLockStore.java
index 82567e2,f57ecb6..0ec8507
--- 1/src/main/java/org/onap/music/lockingservice/cassandra/CassaLockStore.java
--- 2/src/main/java/org/onap/music/lockingservice/cassandra/CassaLockStore.java
+++ b/src/main/java/org/onap/music/lockingservice/cassandra/CassaLockStore.java
@@@ -24,6 -24,7 +24,7 @@@
  package org.onap.music.lockingservice.cassandra;
  
  import java.util.ArrayList;
+ import java.util.Iterator;
  import java.util.List;
  
  import org.onap.music.datastore.MusicDataStore;
@@@ -32,6 -33,8 +33,8 @@@ import org.onap.music.eelf.logging.EELF
  import org.onap.music.exceptions.MusicLockingException;
  import org.onap.music.exceptions.MusicQueryException;
  import org.onap.music.exceptions.MusicServiceException;
+ import org.onap.music.main.DeadlockDetectionUtil;
+ import org.onap.music.main.DeadlockDetectionUtil.OwnershipType;
  import org.onap.music.main.MusicUtil;
  
  import com.datastax.driver.core.ResultSet;
@@@ -60,12 -63,15 +63,15 @@@ public class CassaLockStore 
          private String createTime;
          private String acquireTime;
          private LockType locktype;
-         public LockObject(boolean isLockOwner, String lockRef, String createTime, String acquireTime, LockType locktype) {
+         // Owner is the self-declared client which "owns" this row. It is used for deadlock detection.  It is not (directly) related to isLockOwner.
+         private String owner;
+         public LockObject(boolean isLockOwner, String lockRef, String createTime, String acquireTime, LockType locktype, String owner) {
              this.setIsLockOwner(isLockOwner);
              this.setLockRef(lockRef);
              this.setAcquireTime(acquireTime);
              this.setCreateTime(createTime);
              this.setLocktype(locktype);
+             this.setOwner(owner);
          }
          public boolean getIsLockOwner() {
              return isLockOwner;
@@@ -97,6 -103,12 +103,12 @@@
          public void setLocktype(LockType locktype) {
              this.locktype = locktype;
          }
+         public String getOwner() {
+             return owner;
+         }
+         public void setOwner(String owner) {
+             this.owner = owner;
+         }
      }
      
      /**
@@@ -114,7 -126,7 +126,7 @@@
          table = table_prepend_name+table;
          String tabQuery = "CREATE TABLE IF NOT EXISTS "+keyspace+"."+table
                  + " ( key text, lockReference bigint, createTime text, acquireTime text, guard bigint static, "
-                 + "writeLock boolean, PRIMARY KEY ((key), lockReference) ) "
+                 + "writeLock boolean, owner text, PRIMARY KEY ((key), lockReference) ) "
                  + "WITH CLUSTERING ORDER BY (lockReference ASC);";
          PreparedQueryObject queryObject = new PreparedQueryObject();
          
@@@ -129,22 -141,22 +141,22 @@@
       * @param keyspace of the locks.
       * @param table of the locks.
       * @param lockName is the primary key of the lock table
+      * @param lockType is the type of lock (read/write)
+      * @param owner is the owner of the lock (optional, for deadlock detection)
       * @return the UUID lock reference.
       * @throws MusicServiceException
       * @throws MusicQueryException
       */
-     public String genLockRefandEnQueue(String keyspace, String table, String lockName, LockType locktype) throws MusicServiceException, MusicQueryException, MusicLockingException {
-         return genLockRefandEnQueue(keyspace, table, lockName, locktype, 0);
+     public String genLockRefandEnQueue(String keyspace, String table, String lockName, LockType locktype, String owner) throws MusicServiceException, MusicQueryException, MusicLockingException {
+         return genLockRefandEnQueue(keyspace, table, lockName, locktype, owner, 0);
      }
      
-     private String genLockRefandEnQueue(String keyspace, String table, String lockName, LockType locktype, int count) throws MusicServiceException, MusicQueryException, MusicLockingException {
+     private String genLockRefandEnQueue(String keyspace, String table, String lockName, LockType locktype, String owner, int count) throws MusicServiceException, MusicQueryException, MusicLockingException {
          logger.info(EELFLoggerDelegate.applicationLogger,
                  "Create " + locktype + " lock reference for " +  keyspace + "." + table + "." + lockName);
          String lockTable ="";
          lockTable = table_prepend_name+table;
      
- 
- 
          PreparedQueryObject queryObject = new PreparedQueryObject();
          String selectQuery = "SELECT guard FROM " + keyspace + "." + lockTable + " WHERE key=?;";
  
@@@ -170,7 -182,7 +182,7 @@@
                  " UPDATE " + keyspace + "." + lockTable +
                  " SET guard=? WHERE key=? IF guard = " + (prevGuard == 0 ? "NULL" : "?") +";" +
                  " INSERT INTO " + keyspace + "." + lockTable +
-                 "(key, lockReference, createTime, acquireTime, writeLock) VALUES (?,?,?,?,?) IF NOT EXISTS; APPLY BATCH;";
+                 "(key, lockReference, createTime, acquireTime, writeLock, owner) VALUES (?,?,?,?,?,?) IF NOT EXISTS; APPLY BATCH;";
  
          queryObject.addValue(lockRef);
          queryObject.addValue(lockName);
@@@ -182,6 -194,7 +194,7 @@@
          queryObject.addValue(String.valueOf(lockEpochMillis));
          queryObject.addValue("0");
          queryObject.addValue(locktype==LockType.WRITE ? true : false );
+         queryObject.addValue(owner);
          queryObject.appendQueryString(insQuery);
          boolean pResult = dsHandle.executePut(queryObject, "critical");
          if (!pResult) {// couldn't create lock ref, retry
@@@ -190,14 -203,12 +203,12 @@@
                  logger.warn(EELFLoggerDelegate.applicationLogger, "Unable to create lock reference");
                  throw new MusicLockingException("Unable to create lock reference");
              }
-             return genLockRefandEnQueue(keyspace, table, lockName, locktype, count);
+             return genLockRefandEnQueue(keyspace, table, lockName, locktype, owner, count);
          }
          return "$" + keyspace + "." + table + "." + lockName + "$" + String.valueOf(lockRef);
      }
-     
-     
  
-     /**
+       /**
       * Returns a result set containing the list of clients waiting for a particular lock
       * 
       * @param keyspace
@@@ -269,14 -280,15 +280,15 @@@
          ResultSet results = dsHandle.executeOneConsistencyGet(queryObject);
          Row row = results.one();
          if (row == null || row.isNull("lockReference")) {
-             return new LockObject(false, null, null, null, null);
+             return new LockObject(false, null, null, null, null, null);
          }
          String lockReference = "" + row.getLong("lockReference");
          String createTime = row.getString("createTime");
          String acquireTime = row.getString("acquireTime");
          LockType locktype = row.isNull("writeLock") || row.getBool("writeLock") ? LockType.WRITE : LockType.READ;
+         String owner = row.getString("owner");
  
-         return new LockObject(true, lockReference, createTime, acquireTime, locktype);
+         return new LockObject(true, lockReference, createTime, acquireTime, locktype, owner);
      }
  
      public List<String> getCurrentLockHolders(String keyspace, String table, String key)
@@@ -394,8 -406,9 +406,9 @@@
          String acquireTime = row.getString("acquireTime");
          LockType locktype = row.isNull("writeLock") || row.getBool("writeLock") ? LockType.WRITE : LockType.READ;
          boolean isLockOwner = isLockOwner(keyspace, table, key, lockRef);
+         String owner = row.getString("owner");
  
-         return new LockObject(isLockOwner, lockReference, createTime, acquireTime, locktype);
+         return new LockObject(isLockOwner, lockReference, createTime, acquireTime, locktype, owner);
      }
  
  
@@@ -441,7 -454,8 +454,7 @@@
      }
  
  
 -    public void updateLockAcquireTime(String keyspace, String table, String key, String lockReference)
 -            throws MusicServiceException, MusicQueryException {
 +    public void updateLockAcquireTime(String keyspace, String table, String key, String lockReference) {
          table = table_prepend_name + table;
          PreparedQueryObject queryObject = new PreparedQueryObject();
          Long lockReferenceL = Long.parseLong(lockReference);
@@@ -453,4 -467,45 +466,45 @@@
          dsHandle.getSession().execute(updateQuery);
      }  
  
+     public boolean checkForDeadlock(String keyspace, String table, String lockName, LockType locktype, String owner, boolean forAcquire) throws MusicServiceException, MusicQueryException {
+         if (locktype.equals(LockType.READ)) return false;
+         if (owner==null || owner.length()==0) return false;
+ 
+         String lockTable = table_prepend_name + table;
+         PreparedQueryObject queryObject = new PreparedQueryObject();
+         queryObject.appendQueryString("SELECT key, acquiretime, owner FROM " + keyspace + "." + lockTable);
+         queryObject.appendQueryString(" WHERE writelock = True ALLOW FILTERING");
+ 
+         DeadlockDetectionUtil ddu = new DeadlockDetectionUtil();
+ 
+         ResultSet rs = dsHandle.executeQuorumConsistencyGet(queryObject);
+         logger.debug("rs has " + rs.getAvailableWithoutFetching() + (rs.isFullyFetched()?"":" (or more!)") );
+         Iterator<Row> it = rs.iterator();
+         while (it.hasNext()) {
+             Row row = it.next();
+             logger.debug("key = " + row.getString("key") + ", time = " + row.getString("acquiretime") + ", owner = " + row.getString("owner") );
+             ddu.setExisting(row.getString("key"), row.getString("owner"), ("0".equals(row.getString("acquiretime")))?OwnershipType.CREATED:OwnershipType.ACQUIRED);
+         }
+         boolean deadlock = ddu.checkForDeadlock(lockName, owner, forAcquire?OwnershipType.ACQUIRED:OwnershipType.CREATED);
+         if (deadlock) logger.warn("Deadlock detected when " + owner + " tried to create lock on " + keyspace + "." + lockTable + "." + lockName);
+         return deadlock;
+     }
+ 
+     public List<String> getAllLocksForOwner(String ownerId, String keyspace, String table) throws MusicServiceException, MusicQueryException {
+         List<String> toRet = new ArrayList<String>();
+         String lockTable = table_prepend_name + table;
+         PreparedQueryObject queryObject = new PreparedQueryObject();
+         queryObject.appendQueryString("SELECT key, lockreference FROM " + keyspace + "." + lockTable);
+         queryObject.appendQueryString(" WHERE owner = '" + ownerId + "' ALLOW FILTERING");
+ 
+         ResultSet rs = dsHandle.executeQuorumConsistencyGet(queryObject);
+         Iterator<Row> it = rs.iterator();
+         while (it.hasNext()) {
+             Row row = it.next();
+             toRet.add(row.getString("key") + "$" + row.getLong("lockreference"));
+         }
+         return toRet;
+     }
+ 
+ 
  }

diff --combined src/main/java/org/onap/music/rest/RestMusicLocksAPI.java
index 5ce0f42,c08fc5d..b839c7f
--- 1/src/main/java/org/onap/music/rest/RestMusicLocksAPI.java
--- 2/src/main/java/org/onap/music/rest/RestMusicLocksAPI.java
+++ b/src/main/java/org/onap/music/rest/RestMusicLocksAPI.java
@@@ -116,6 -116,7 +116,7 @@@ public class RestMusicLocksAPI 
              @ApiParam(value = "Authorization", required = true) @HeaderParam(MusicUtil.AUTHORIZATION) String authorization,
              @ApiParam(value = "AID", required = false, hidden = true) @HeaderParam("aid") String aid,
              JsonLock lockObject,
+             @ApiParam(value = "Lock Owner", required = false) @HeaderParam("owner") String owner,
              @ApiParam(value = "Application namespace",
                              required = false, hidden = true) @HeaderParam("ns") String ns) throws Exception{
          try {
@@@ -136,7 -137,7 +137,7 @@@
              }
              String lockId;
              try {
-                 lockId= MusicCore.createLockReference(lockName, locktype);
+                 lockId= MusicCore.createLockReference(lockName, locktype, owner);
              } catch (MusicLockingException e) {
                  return response.status(Status.BAD_REQUEST).entity(new JsonResponse(ResultType.FAILURE).setError(e.getMessage()).toMap()).build();
              }
@@@ -357,7 -358,7 +358,7 @@@
              @ApiParam(value = "Authorization", required = true) @HeaderParam(MusicUtil.AUTHORIZATION) String authorization,
              @ApiParam(value = "AID", required = false, hidden = true) @HeaderParam("aid") String aid,
              @ApiParam(value = "Application namespace",
 -                            required = false, hidden = true) @HeaderParam("ns") String ns) throws Exception{
 +                            required = false, hidden = true) @HeaderParam("ns") String ns) {
          try {
              ResponseBuilder response = MusicUtil.buildVersionResponse(VERSION, minorVersion, patchVersion);
              Map<String, Object> resultMap = MusicCore.validateLock(lockName);
@@@ -417,7 -418,7 +418,7 @@@
              @ApiParam(value = "Authorization", required = true) @HeaderParam(MusicUtil.AUTHORIZATION) String authorization,
              @ApiParam(value = "AID", required = false, hidden = true) @HeaderParam("aid") String aid,
              @ApiParam(value = "Application namespace",
 -                            required = false, hidden = true) @HeaderParam("ns") String ns) throws Exception{
 +                            required = false, hidden = true) @HeaderParam("ns") String ns) {
          try {
              ResponseBuilder response = MusicUtil.buildVersionResponse(VERSION, minorVersion, patchVersion);
              Map<String, Object> resultMap = MusicCore.validateLock(lockName);