/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
*/
package org.apache.s4.ft;
import org.apache.s4.ft.SafeKeeper.StorageResultCode;
import java.util.HashSet;
import java.util.Set;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.RejectedExecutionException;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import org.apache.log4j.Logger;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisPoolConfig;
/**
* <p>
* This class implements a storage backend based on Redis. Redis is a key-value
* store.
* </p>
* <p>
* See {@link http://redis.io/} for more information.
* </p>
* <p>
* Redis must be running as an external service. References to this external
* services must be injected during the initialization of the S4 platform.
* </p>
*
*
*/
public class RedisStateStorage implements StateStorage {
static Logger logger = Logger.getLogger("s4-ft");
private JedisPool jedisPool;
private String redisHost;
private int redisPort;
public void clear() {
Jedis jedis = jedisPool.getResource();
try {
jedis.flushAll();
} finally {
jedisPool.returnResource(jedis);
}
}
public void init() {
JedisPoolConfig jedisPoolConfig = new JedisPoolConfig();
// TODO optional parameterization
jedisPool = new JedisPool(jedisPoolConfig, redisHost, redisPort);
}
@Override
public void saveState(SafeKeeperId key, byte[] state, StorageCallback callback) {
Jedis jedis = jedisPool.getResource();
String statusCode = "UNKNOWN";
try {
statusCode = jedis.set(key.getStringRepresentation().getBytes(), state);
} finally {
jedisPool.returnResource(jedis);
}
if ("OK".equals(statusCode)) {
callback.storageOperationResult(StorageResultCode.SUCCESS, "Redis result code is [" + statusCode + "] for key [" + key.toString() +"]");
} else {
callback.storageOperationResult(StorageResultCode.FAILURE, "Unexpected redis result code : [" + statusCode + "] for key [" + key.toString() +"]");
}
}
@Override
public byte[] fetchState(SafeKeeperId key) {
Jedis jedis = jedisPool.getResource();
try {
return jedis.get(key.getStringRepresentation().getBytes());
} finally {
jedisPool.returnResource(jedis);
}
}
@Override
public Set<SafeKeeperId> fetchStoredKeys() {
Jedis jedis = jedisPool.getResource();
try {
Set<String> keys = jedis.keys("*");
Set<SafeKeeperId> result = new HashSet<SafeKeeperId>(keys.size());
for (String s : keys)
result.add(new SafeKeeperId(s));
return result;
} finally {
jedisPool.returnResource(jedis);
}
}
public String getRedisHost() {
return redisHost;
}
public void setRedisHost(String redisHost) {
this.redisHost = redisHost;
}
public int getRedisPort() {
return redisPort;
}
public void setRedisPort(int redisPort) {
this.redisPort = redisPort;
}
}