Use connection pooling for locking

Modified distributed locking to use connection pooling.
Add comment for new dataSource parameter.

Change-Id: I5dc33605797f95072af9b6911a468457f6fd9f3d
Issue-ID: POLICY-910
Signed-off-by: Jim Hahn <jrh3@att.com>

diff --git a/feature-distributed-locking/pom.xml b/feature-distributed-locking/pom.xml
index 53a7a6d..ddb7c71 100644 (file)
--- a/feature-distributed-locking/pom.xml
+++ b/feature-distributed-locking/pom.xml
@@ -104,6 +104,16 @@
                <version>${project.version}</version>
                <scope>provided</scope>
        </dependency>
+    <dependency>
+        <groupId>org.apache.commons</groupId>
+        <artifactId>commons-dbcp2</artifactId>
+        <version>2.1.1</version>
+    </dependency>
+    <dependency>
+        <groupId>org.apache.commons</groupId>
+        <artifactId>commons-pool2</artifactId>
+        <version>2.4.2</version>
+    </dependency>
        <dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>

diff --git a/feature-distributed-locking/src/main/java/org/onap/policy/distributed/locking/DistributedLockingFeature.java b/feature-distributed-locking/src/main/java/org/onap/policy/distributed/locking/DistributedLockingFeature.java
index 019452a..b30fca7 100644 (file)
--- a/feature-distributed-locking/src/main/java/org/onap/policy/distributed/locking/DistributedLockingFeature.java
+++ b/feature-distributed-locking/src/main/java/org/onap/policy/distributed/locking/DistributedLockingFeature.java
@@ -20,15 +20,16 @@
 package org.onap.policy.distributed.locking;
 
 import java.sql.Connection;
-import java.sql.DriverManager;
 import java.sql.PreparedStatement;
 import java.sql.SQLException;
+import java.util.Properties;
 import java.util.UUID;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.TimeUnit;
-
+import org.apache.commons.dbcp2.BasicDataSource;
+import org.apache.commons.dbcp2.BasicDataSourceFactory;
 import org.onap.policy.common.utils.properties.exception.PropertyException;
 import org.onap.policy.drools.core.lock.LockRequestFuture;
 import org.onap.policy.drools.core.lock.PolicyResourceLockFeatureAPI;
@@ -60,6 +61,11 @@ public class DistributedLockingFeature implements PolicyEngineFeatureAPI, Policy
         */
        private ScheduledExecutorService scheduledExecutorService;
        
+       /**
+        * Data source used to connect to the DB containing locks.
+        */
+       private BasicDataSource dataSource;
+       
        /**
         * UUID 
         */
@@ -79,7 +85,7 @@ public class DistributedLockingFeature implements PolicyEngineFeatureAPI, Policy
        @Override
        public Future<Boolean> beforeLock(String resourceId, String owner, Callback callback) {
                
-               TargetLock tLock = new TargetLock(resourceId, uuid, owner, lockProps);
+               TargetLock tLock = new TargetLock(resourceId, uuid, owner, lockProps, dataSource);
                
                return new LockRequestFuture(resourceId, owner, tLock.lock());
                                
@@ -87,21 +93,21 @@ public class DistributedLockingFeature implements PolicyEngineFeatureAPI, Policy
 
        @Override
        public OperResult beforeUnlock(String resourceId, String owner) {
-               TargetLock tLock = new TargetLock(resourceId, uuid, owner, lockProps);
+               TargetLock tLock = new TargetLock(resourceId, uuid, owner, lockProps, dataSource);
                
                return(tLock.unlock() ? OperResult.OPER_ACCEPTED : OperResult.OPER_DENIED);
        }
        
        @Override
        public OperResult beforeIsLockedBy(String resourceId, String owner) {
-               TargetLock tLock = new TargetLock(resourceId, uuid, owner, lockProps);
+               TargetLock tLock = new TargetLock(resourceId, uuid, owner, lockProps, dataSource);
 
         return(tLock.isActive() ? OperResult.OPER_ACCEPTED : OperResult.OPER_DENIED);
        }
        
        @Override
        public OperResult beforeIsLocked(String resourceId) {
-               TargetLock tLock = new TargetLock(resourceId, uuid, "dummyOwner", lockProps);
+               TargetLock tLock = new TargetLock(resourceId, uuid, "dummyOwner", lockProps, dataSource);
 
         return(tLock.isLocked() ? OperResult.OPER_ACCEPTED : OperResult.OPER_DENIED);
        }
@@ -111,15 +117,23 @@ public class DistributedLockingFeature implements PolicyEngineFeatureAPI, Policy
 
                try {
                        this.lockProps = new DistributedLockingProperties(SystemPersistence.manager.getProperties(DistributedLockingFeature.CONFIGURATION_PROPERTIES_NAME));
+                       this.dataSource = makeDataSource();
                } catch (PropertyException e) {
                        logger.error("DistributedLockingFeature feature properies have not been loaded", e);
                        throw new DistributedLockingFeatureException(e);
+               } catch(InterruptedException e) {
+            logger.error("DistributedLockingFeature failed to create data source", e);
+                   Thread.currentThread().interrupt();
+            throw new DistributedLockingFeatureException(e);
+        } catch(Exception e) {
+            logger.error("DistributedLockingFeature failed to create data source", e);
+            throw new DistributedLockingFeatureException(e);
                }
                
                long heartbeatInterval = this.lockProps.getHeartBeatIntervalProperty();
                
                cleanLockTable();
-               initHeartbeat(lockProps);
+               initHeartbeat();
                
                this.scheduledExecutorService = Executors.newScheduledThreadPool(1);
                this.scheduledExecutorService.scheduleAtFixedRate(heartbeat, heartbeatInterval, heartbeatInterval, TimeUnit.MILLISECONDS);
@@ -127,6 +141,24 @@ public class DistributedLockingFeature implements PolicyEngineFeatureAPI, Policy
        }
        
        /**
+        * @return a new, pooled data source
+        * @throws Exception
+        */
+       private BasicDataSource makeDataSource() throws Exception {
+        Properties props = new Properties();
+        props.put("driverClassName", lockProps.getDbDriver());
+        props.put("url", lockProps.getDbUrl());
+        props.put("username", lockProps.getDbUser());
+        props.put("password", lockProps.getDbPwd());
+        props.put("testOnBorrow", "true");
+        props.put("poolPreparedStatements", "true");
+
+        // additional properties are listed in the GenericObjectPool API
+        
+        return BasicDataSourceFactory.createDataSource(props);
+    }
+
+    /**
         * This method kills the heartbeat thread and calls refreshLockTable which removes
         * any records from the db where the current host is the owner.
         */
@@ -142,9 +174,7 @@ public class DistributedLockingFeature implements PolicyEngineFeatureAPI, Policy
         */
        private void cleanLockTable() {
                
-           try (Connection conn = DriverManager.getConnection(lockProps.getDbUrl(), 
-                       lockProps.getDbUser(),
-                       lockProps.getDbPwd());
+           try (Connection conn = dataSource.getConnection();
                PreparedStatement statement = conn.prepareStatement("DELETE FROM pooling.locks WHERE host = ? OR expirationTime < ?");
                ){
                        
@@ -161,8 +191,8 @@ public class DistributedLockingFeature implements PolicyEngineFeatureAPI, Policy
        /**
         * Initialize the static heartbeat object
         */
-       private static void initHeartbeat(DistributedLockingProperties lockProps) {
-               heartbeat = new Heartbeat(uuid, lockProps);
+       private void initHeartbeat() {
+               heartbeat = new Heartbeat(uuid, lockProps, dataSource);
                
        }
        

diff --git a/feature-distributed-locking/src/main/java/org/onap/policy/distributed/locking/Heartbeat.java b/feature-distributed-locking/src/main/java/org/onap/policy/distributed/locking/Heartbeat.java
index edd0782..ccfb4c7 100644 (file)
--- a/feature-distributed-locking/src/main/java/org/onap/policy/distributed/locking/Heartbeat.java
+++ b/feature-distributed-locking/src/main/java/org/onap/policy/distributed/locking/Heartbeat.java
@@ -21,12 +21,11 @@
 package org.onap.policy.distributed.locking;
 
 import java.sql.Connection;
-import java.sql.DriverManager;
 import java.sql.PreparedStatement;
 import java.sql.SQLException;
 import java.util.UUID;
 import java.util.concurrent.CountDownLatch;
-
+import org.apache.commons.dbcp2.BasicDataSource;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -45,6 +44,11 @@ public class Heartbeat implements Runnable{
         * Properties object containing properties needed by class
         */
        private DistributedLockingProperties lockProps;
+    
+    /**
+     * Data source used to connect to the DB containing locks.
+     */
+    private BasicDataSource dataSource;
 
        /**
         * UUID 
@@ -60,9 +64,11 @@ public class Heartbeat implements Runnable{
         * 
         * @param uuid
         * @param lockProps
+        * @param dataSource 
         */
-       public Heartbeat(UUID uuid, DistributedLockingProperties lockProps) {
+       public Heartbeat(UUID uuid, DistributedLockingProperties lockProps, BasicDataSource dataSource) {
                this.lockProps = lockProps;
+               this.dataSource = dataSource;
                this.uuid = uuid;
                this.latch = new CountDownLatch(1);
        }
@@ -81,8 +87,7 @@ public class Heartbeat implements Runnable{
                
                long expirationAge = lockProps.getAgingProperty();
 
-               try (Connection conn = DriverManager.getConnection(lockProps.getDbUrl(), lockProps.getDbUser(),
-                               lockProps.getDbPwd());
+               try (Connection conn = dataSource.getConnection();
                        PreparedStatement statement = conn
                                                .prepareStatement("UPDATE pooling.locks SET expirationTime = ? WHERE host = ?");) {
 

diff --git a/feature-distributed-locking/src/main/java/org/onap/policy/distributed/locking/TargetLock.java b/feature-distributed-locking/src/main/java/org/onap/policy/distributed/locking/TargetLock.java
index 4f09dc2..d57de1f 100644 (file)
--- a/feature-distributed-locking/src/main/java/org/onap/policy/distributed/locking/TargetLock.java
+++ b/feature-distributed-locking/src/main/java/org/onap/policy/distributed/locking/TargetLock.java
@@ -20,12 +20,11 @@
 package org.onap.policy.distributed.locking;
 
 import java.sql.Connection;
-import java.sql.DriverManager;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.util.UUID;
-
+import org.apache.commons.dbcp2.BasicDataSource;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -42,6 +41,11 @@ public class TargetLock {
         * Properties object containing properties needed by class
         */
        private DistributedLockingProperties lockProps;
+    
+    /**
+     * Data source used to connect to the DB containing locks.
+     */
+    private BasicDataSource dataSource;
 
        /**
         * UUID 
@@ -58,12 +62,14 @@ public class TargetLock {
         * 
         * @param resourceId ID of the entity we want to lock
         * @param lockProps Properties object containing properties needed by class
+        * @param dataSource used to connect to the DB containing locks
         */
-       public TargetLock (String resourceId, UUID uuid, String owner, DistributedLockingProperties lockProps) {
+       public TargetLock (String resourceId, UUID uuid, String owner, DistributedLockingProperties lockProps, BasicDataSource dataSource) {
                this.resourceId = resourceId;
                this.uuid = uuid;
                this.owner = owner;
                this.lockProps = lockProps;
+               this.dataSource = dataSource;
        }
        
        /**
@@ -89,8 +95,7 @@ public class TargetLock {
        private boolean grabLock() {
 
                // try to insert a record into the table(thereby grabbing the lock)
-               try (Connection conn = DriverManager.getConnection(lockProps.getDbUrl(), lockProps.getDbUser(),
-                               lockProps.getDbPwd());
+               try (Connection conn = dataSource.getConnection();
 
                                PreparedStatement statement = conn.prepareStatement(
                                                "INSERT INTO pooling.locks (resourceId, host, owner, expirationTime) values (?, ?, ?, ?)")) {
@@ -116,8 +121,7 @@ public class TargetLock {
         */
        private boolean secondGrab() {
 
-               try (Connection conn = DriverManager.getConnection(lockProps.getDbUrl(), lockProps.getDbUser(),
-                               lockProps.getDbPwd());
+               try (Connection conn = dataSource.getConnection();
 
                                PreparedStatement updateStatement = conn.prepareStatement(
                                                "UPDATE pooling.locks SET host = ?, owner = ?, expirationTime = ? WHERE expirationTime <= ? AND resourceId = ?");
@@ -161,8 +165,7 @@ public class TargetLock {
         */
        private boolean deleteLock() {
 
-               try (Connection conn = DriverManager.getConnection(lockProps.getDbUrl(), lockProps.getDbUser(),
-                               lockProps.getDbPwd());
+               try (Connection conn = dataSource.getConnection();
 
                                PreparedStatement deleteStatement = conn.prepareStatement(
                                                "DELETE FROM pooling.locks WHERE resourceId = ? AND owner = ? AND host = ?")) {
@@ -184,8 +187,7 @@ public class TargetLock {
         * Is the lock active
         */
        public boolean isActive() {
-               try (Connection conn = DriverManager.getConnection(lockProps.getDbUrl(), lockProps.getDbUser(),
-                               lockProps.getDbPwd());
+               try (Connection conn = dataSource.getConnection();
 
                                PreparedStatement selectStatement = conn.prepareStatement(
                                                "SELECT * FROM pooling.locks WHERE resourceId = ? AND host = ? AND owner= ? AND expirationTime >= ?")) {
@@ -215,8 +217,7 @@ public class TargetLock {
         */
        public boolean isLocked() {
 
-               try (Connection conn = DriverManager.getConnection(lockProps.getDbUrl(), lockProps.getDbUser(),
-                               lockProps.getDbPwd());
+               try (Connection conn = dataSource.getConnection();
                        
                                PreparedStatement selectStatement = conn
                                                .prepareStatement("SELECT * FROM pooling.locks WHERE resourceId = ? AND expirationTime >= ?")) {