Revert "music core implemented as a service"

This reverts commit 7addd52dc73e6571028ca7f6a018e75ec1c9b0ca.

Change-Id: I0875ce10521363b8e17eb6cd2cf9d8848e572bea
Issue-ID: MUSIC-189
Signed-off-by: Tschaen, Brendan <ctschaen@att.com>

5 files changed, 219 insertions, 173 deletions

diff --git a/src/main/java/org/onap/music/datastore/MusicDataStore.java b/src/main/java/org/onap/music/datastore/CassaDataStore.java
index 725cefe6..14934f6e 100644
--- a/src/main/java/org/onap/music/datastore/MusicDataStore.java
+++ b/src/main/java/org/onap/music/datastore/CassaDataStore.java
@@ -89,7 +89,7 @@ import com.sun.jersey.core.util.Base64;
  * @author bharathb
  *
  */
-public class MusicDataStore {
+public class CassaDataStore {
 
     private Session session;
     private Cluster cluster;
@@ -119,12 +119,12 @@ public class MusicDataStore {
 
 
 
-    private EELFLoggerDelegate logger = EELFLoggerDelegate.getLogger(MusicDataStore.class);
+    private EELFLoggerDelegate logger = EELFLoggerDelegate.getLogger(CassaDataStore.class);
 
     /**
      * 
      */
-    public MusicDataStore() {
+    public CassaDataStore() {
         connectToCassaCluster();
     }
 
@@ -133,7 +133,7 @@ public class MusicDataStore {
      * @param cluster
      * @param session
      */
-    public MusicDataStore(Cluster cluster, Session session) {
+    public CassaDataStore(Cluster cluster, Session session) {
         this.session = session;
         this.cluster = cluster;
     }
@@ -143,7 +143,7 @@ public class MusicDataStore {
      * @param remoteIp
      * @throws MusicServiceException
      */
-    public MusicDataStore(String remoteIp) {
+    public CassaDataStore(String remoteIp) {
         try {
             connectToCassaCluster(remoteIp);
         } catch (MusicServiceException e) {
diff --git a/src/main/java/org/onap/music/datastore/CassaLockStore.java b/src/main/java/org/onap/music/datastore/CassaLockStore.java
new file mode 100644
index 00000000..e03a1c07
--- /dev/null
+++ b/src/main/java/org/onap/music/datastore/CassaLockStore.java
@@ -0,0 +1,173 @@
+package org.onap.music.datastore;
+
+import java.util.UUID;
+
+import org.onap.music.eelf.logging.EELFLoggerDelegate;
+import org.onap.music.exceptions.MusicQueryException;
+import org.onap.music.exceptions.MusicServiceException;
+import org.onap.music.main.MusicUtil;
+
+import com.datastax.driver.core.ResultSet;
+import com.datastax.driver.core.Row;
+import com.datastax.driver.core.utils.UUIDs;
+
+/*
+ * This is the lock store that is built on top of Cassandra that is used by MUSIC to maintain lock state. 
+ */
+
+public class CassaLockStore {
+	
+	private EELFLoggerDelegate logger = EELFLoggerDelegate.getLogger(CassaLockStore.class);
+	
+	public class LockObject{
+		public String lockRef;
+		public String createTime;
+		public String acquireTime;
+		public LockObject(String lockRef, String createTime, 	String acquireTime) {
+			this.lockRef = lockRef;
+			this.acquireTime = acquireTime;
+			this.createTime = createTime;
+			
+		}
+	}
+	CassaDataStore dsHandle;
+	public CassaLockStore() {
+		dsHandle = new CassaDataStore();
+	}
+	
+	public CassaLockStore(CassaDataStore dsHandle) {
+		this.dsHandle=dsHandle;
+	}
+
+    
+	/**
+	 * 
+	 * This method creates a shadow locking table for every main table in Cassandra. This table tracks all information regarding locks. 
+	 * @param keyspace of the application. 
+	 * @param table of the application. 
+	 * @return true if the operation was successful.
+	 * @throws MusicServiceException
+	 * @throws MusicQueryException
+	 */
+	public boolean createLockQueue(String keyspace, String table) throws MusicServiceException, MusicQueryException {
+        logger.info(EELFLoggerDelegate.applicationLogger,
+                "Create lock queue/table for " +  keyspace+"."+table);
+		table = "lockQ_"+table; 
+		String tabQuery = "CREATE TABLE IF NOT EXISTS "+keyspace+"."+table
+				+ " ( key text, lockReference bigint, createTime text, acquireTime text, guard bigint static, PRIMARY KEY ((key), lockReference) ) "
+				+ "WITH CLUSTERING ORDER BY (lockReference ASC);";
+		System.out.println(tabQuery);
+		PreparedQueryObject queryObject = new PreparedQueryObject(); 
+		
+		queryObject.appendQueryString(tabQuery);
+		boolean result;
+		result = dsHandle.executePut(queryObject, "eventual");
+		return result;
+	}
+
+	/**
+	 * This method creates a lock reference for each invocation. The lock references are monotonically increasing timestamps.
+	 * @param keyspace of the locks.
+	 * @param table of the locks.
+	 * @param lockName is the primary key of the lock table
+	 * @return the UUID lock reference.
+	 * @throws MusicServiceException
+	 * @throws MusicQueryException
+	 */
+	public String genLockRefandEnQueue(String keyspace, String table, String lockName) throws MusicServiceException, MusicQueryException {
+        logger.info(EELFLoggerDelegate.applicationLogger,
+                "Create lock reference for " +  keyspace + "." + table + "." + lockName);
+		table = "lockQ_" + table;
+		long lockEpochMillis = System.currentTimeMillis();
+		long lockRef = lockEpochMillis;
+
+		logger.info(EELFLoggerDelegate.applicationLogger,
+				"Created lock reference for " +  keyspace + "." + table + "." + lockName + ":" + lockRef);
+
+        PreparedQueryObject queryObject = new PreparedQueryObject();
+        String defaultQuery = " UPDATE " + keyspace + "." + table + " SET guard=-1 WHERE key=? IF guard = NULL;";
+
+        queryObject.addValue(lockName);
+        queryObject.appendQueryString(defaultQuery);
+        boolean dqResult = dsHandle.executePut(queryObject, "critical");
+//        System.out.println("dqResult: " + dqResult);
+
+
+        queryObject = new PreparedQueryObject();
+		String insQuery = "BEGIN BATCH" +
+                " UPDATE " + keyspace + "." + table + " SET guard=? WHERE key=? IF guard < ?;" +
+                " INSERT INTO " + keyspace + "." + table +
+				"(key, lockReference, createTime, acquireTime) VALUES (?,?,?,?) IF NOT EXISTS; APPLY BATCH;";
+
+        queryObject.addValue(lockRef);
+        queryObject.addValue(lockName);
+        queryObject.addValue(lockRef);
+
+        queryObject.addValue(lockName);
+        queryObject.addValue(lockRef);
+        queryObject.addValue(String.valueOf(lockEpochMillis));
+        queryObject.addValue("0");
+        queryObject.appendQueryString(insQuery);
+        boolean pResult = dsHandle.executePut(queryObject, "critical");
+//        System.out.println("pResult: " + pResult);
+		return String.valueOf(lockRef);
+	}
+	
+	
+	/**
+	 * This method returns the top of lock table/queue for the key. 
+	 * @param keyspace of the application. 
+	 * @param table of the application. 
+	 * @param key is the primary key of the application table
+	 * @return the UUID lock reference.
+	 * @throws MusicServiceException
+	 * @throws MusicQueryException
+	 */
+	public LockObject peekLockQueue(String keyspace, String table, String key) throws MusicServiceException, MusicQueryException{
+        logger.info(EELFLoggerDelegate.applicationLogger,
+                "Peek in lock table for " +  keyspace+"."+table+"."+key);
+		table = "lockQ_"+table; 
+		String selectQuery = "select * from "+keyspace+"."+table+" where key='"+key+"' LIMIT 1;";	
+        PreparedQueryObject queryObject = new PreparedQueryObject();
+        queryObject.appendQueryString(selectQuery);
+		ResultSet results = dsHandle.executeEventualGet(queryObject);
+		Row row = results.one();
+		String lockReference = "" + row.getLong("lockReference");
+		String createTime = row.getString("createTime");
+		String acquireTime = row.getString("acquireTime");
+
+		return new LockObject(lockReference, createTime,acquireTime);
+	}
+	
+	
+	/**
+	 * This method removes the lock ref from the lock table/queue for the key. 
+	 * @param keyspace of the application. 
+	 * @param table of the application. 
+	 * @param key is the primary key of the application table
+	 * @param lockReference the lock reference that needs to be dequeued.
+	 * @throws MusicServiceException
+	 * @throws MusicQueryException
+	 */	
+	public void deQueueLockRef(String keyspace, String table, String key, String lockReference) throws MusicServiceException, MusicQueryException{
+		table = "lockQ_"+table; 
+        PreparedQueryObject queryObject = new PreparedQueryObject();
+        Long lockReferenceL = Long.parseLong(lockReference);
+        String deleteQuery = "delete from "+keyspace+"."+table+" where key='"+key+"' AND lockReference ="+lockReferenceL+" IF EXISTS;";
+        queryObject.appendQueryString(deleteQuery);
+		dsHandle.executePut(queryObject, "critical");	
+	}
+	
+
+	public void updateLockAcquireTime(String keyspace, String table, String key, String lockReference) throws MusicServiceException, MusicQueryException{
+		table = "lockQ_"+table; 
+        PreparedQueryObject queryObject = new PreparedQueryObject();
+        Long lockReferenceL = Long.parseLong(lockReference);
+        String updateQuery = "update "+keyspace+"."+table+" set acquireTime='"+ System.currentTimeMillis()+"' where key='"+key+"' AND lockReference = "+lockReferenceL+" IF EXISTS;";
+        queryObject.appendQueryString(updateQuery);
+		dsHandle.executePut(queryObject, "eventual");	
+
+	}
+	
+
+}
diff --git a/src/main/java/org/onap/music/datastore/Condition.java b/src/main/java/org/onap/music/datastore/Condition.java
deleted file mode 100644
index f08a8754..00000000
--- a/src/main/java/org/onap/music/datastore/Condition.java
+++ /dev/null
@@ -1,53 +0,0 @@
-/*
- * ============LICENSE_START==========================================
- * org.onap.music
- * ===================================================================
- *  Copyright (c) 2017 AT&T Intellectual Property
- * ===================================================================
- *  Licensed under the Apache License, Version 2.0 (the "License");
- *  you may not use this file except in compliance with the License.
- *  You may obtain a copy of the License at
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- *  Unless required by applicable law or agreed to in writing, software
- *  distributed under the License is distributed on an "AS IS" BASIS,
- *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- *  See the License for the specific language governing permissions and
- *  limitations under the License.
- * 
- * ============LICENSE_END=============================================
- * ====================================================================
- */
-package org.onap.music.datastore;
-
-import java.util.Map;
-
-import org.onap.music.eelf.logging.EELFLoggerDelegate;
-import org.onap.music.service.MusicCoreService;
-import org.onap.music.service.impl.MusicCassaCore;
-
-import com.datastax.driver.core.ResultSet;
-import com.datastax.driver.core.Row;
-
-
-
-    public class Condition {
-        Map<String, Object> conditions;
-        PreparedQueryObject selectQueryForTheRow;
-        private static EELFLoggerDelegate logger = EELFLoggerDelegate.getLogger(Condition.class);
-        private static MusicCoreService musicCore = MusicCassaCore.getInstance();
-
-        public Condition(Map<String, Object> conditions, PreparedQueryObject selectQueryForTheRow) {
-            this.conditions = conditions;
-            this.selectQueryForTheRow = selectQueryForTheRow;
-        }
-
-        public boolean testCondition() throws Exception {
-            // first generate the row
-            ResultSet results = musicCore.quorumGet(selectQueryForTheRow);
-            Row row = results.one();
-            return MusicDataStoreHandle.getDSHandle().doesRowSatisfyCondition(row, conditions);
-        }
-    }
-
diff --git a/src/main/java/org/onap/music/datastore/MusicDataStoreHandle.java b/src/main/java/org/onap/music/datastore/MusicDataStoreHandle.java
deleted file mode 100644
index a2d9386b..00000000
--- a/src/main/java/org/onap/music/datastore/MusicDataStoreHandle.java
+++ /dev/null
@@ -1,115 +0,0 @@
-/*
- * ============LICENSE_START==========================================
- * org.onap.music
- * ===================================================================
- *  Copyright (c) 2017 AT&T Intellectual Property
- * ===================================================================
- *  Licensed under the Apache License, Version 2.0 (the "License");
- *  you may not use this file except in compliance with the License.
- *  You may obtain a copy of the License at
- * 
- *     http://www.apache.org/licenses/LICENSE-2.0
- * 
- *  Unless required by applicable law or agreed to in writing, software
- *  distributed under the License is distributed on an "AS IS" BASIS,
- *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- *  See the License for the specific language governing permissions and
- *  limitations under the License.
- * 
- * ============LICENSE_END=============================================
- * ====================================================================
- */
-package org.onap.music.datastore;
-
-import java.util.HashMap;
-import java.util.Map;
-
-import org.onap.music.eelf.logging.EELFLoggerDelegate;
-import org.onap.music.exceptions.MusicServiceException;
-import org.onap.music.main.MusicUtil;
-import org.onap.music.service.impl.MusicCassaCore;
-
-import com.datastax.driver.core.ResultSet;
-import com.datastax.driver.core.TableMetadata;
-
-public class MusicDataStoreHandle {
-	
-	 public static MusicDataStore mDstoreHandle = null;
-	 private static EELFLoggerDelegate logger = EELFLoggerDelegate.getLogger(MusicDataStoreHandle.class);
-	
-    /**
-     * 
-     * @param remoteIp
-     * @return
-     */
-    public static MusicDataStore getDSHandle(String remoteIp) {
-        logger.info(EELFLoggerDelegate.applicationLogger,"Acquiring data store handle");
-        long start = System.currentTimeMillis();
-        if (mDstoreHandle == null) {
-        	try {
-    			MusicUtil.loadProperties();
-    		} catch (Exception e) {
-    			logger.error(EELFLoggerDelegate.errorLogger, "No properties file defined. Falling back to default.");
-    		}
-            mDstoreHandle = new MusicDataStore(remoteIp);
-        }
-        long end = System.currentTimeMillis();
-        logger.info(EELFLoggerDelegate.applicationLogger,"Time taken to acquire data store handle:" + (end - start) + " ms");
-        return mDstoreHandle;
-    }
-
-    /**
-     * 
-     * @return
-     * @throws MusicServiceException 
-     */
-    public static MusicDataStore getDSHandle() throws MusicServiceException {
-		
-        logger.info(EELFLoggerDelegate.applicationLogger,"Acquiring data store handle");
-        long start = System.currentTimeMillis();
-        if (mDstoreHandle == null) {
-        	try {
-    			MusicUtil.loadProperties();
-    		} catch (Exception e) {
-    			logger.error(EELFLoggerDelegate.errorLogger, "No properties file defined. Falling back to default.");
-    		}
-            // Quick Fix - Best to put this into every call to getDSHandle?
-            if (! MusicUtil.getMyCassaHost().equals("localhost") ) {
-                mDstoreHandle = new MusicDataStore(MusicUtil.getMyCassaHost());
-            } else {
-                mDstoreHandle = new MusicDataStore();
-            }
-        }
-        if(mDstoreHandle.getSession() == null) {
-        	String message = "Connection to Cassandra has not been enstablished."
-        			+ " Please check connection properites and reboot.";
-        	logger.info(EELFLoggerDelegate.applicationLogger, message);
-            throw new MusicServiceException(message);
-        }
-        long end = System.currentTimeMillis();
-        logger.info(EELFLoggerDelegate.applicationLogger,"Time taken to acquire data store handle:" + (end - start) + " ms");
-        return mDstoreHandle;
-    }
-    
-    /**
-     * 
-     * @param keyspace
-     * @param tablename
-     * @return
-     * @throws MusicServiceException 
-     */
-    public static TableMetadata returnColumnMetadata(String keyspace, String tablename) throws MusicServiceException {
-        return MusicDataStoreHandle.getDSHandle().returnColumnMetadata(keyspace, tablename);
-    }
-    
-    /**
-     * 
-     * @param results
-     * @return
-     * @throws MusicServiceException 
-     */
-    public static Map<String, HashMap<String, Object>> marshallResults(ResultSet results) throws MusicServiceException {
-        return MusicDataStoreHandle.getDSHandle().marshalData(results);
-    }
-
-}
diff --git a/src/main/java/org/onap/music/datastore/MusicLockState.java b/src/main/java/org/onap/music/datastore/MusicLockState.java
new file mode 100644
index 00000000..60a15b13
--- /dev/null
+++ b/src/main/java/org/onap/music/datastore/MusicLockState.java
@@ -0,0 +1,41 @@
+package org.onap.music.datastore;
+public class MusicLockState {
+    public enum LockStatus {
+        UNLOCKED, BEING_LOCKED, LOCKED
+    };// captures the state of the lock
+    
+    private LockStatus lockStatus;
+    private String lockHolder;
+    private String errorMessage = null;
+    
+    public String getErrorMessage() {
+		return errorMessage;
+	}
+
+	public void setErrorMessage(String errorMessage) {
+		this.errorMessage = errorMessage;
+	}
+
+	public MusicLockState(LockStatus lockStatus, String lockHolder) {
+		super();
+        this.lockStatus = lockStatus;
+		this.lockHolder = lockHolder;
+	}
+
+	public LockStatus getLockStatus() {
+        return lockStatus;
+    }
+
+    public void setLockStatus(LockStatus lockStatus) {
+        this.lockStatus = lockStatus;
+    }
+
+    public String getLockHolder() {
+        return lockHolder;
+    }
+
+    public void setLockHolder(String lockHolder) {
+        this.lockHolder = lockHolder;
+    }
+
+}