Jedis訪問多Master的哨兵模式，實現Redis集羣高可用
在使用Jedis訪問哨兵（Sentinel）模式的集羣時，Jedis默認提供JedisSentinelPool組件來訪問哨兵模式的Redis節點，但是很遺憾JedisSentinelPool只支持一個Master的節點，在訪問多個Master節點的哨兵集羣時，卻沒有很好的組件支持。雖然目前Redis Cluster提供了很好的高可用集羣解決方案，也有完善的客戶端支持，如Lettuce、Redisson等；不過對於多Master哨兵模式集羣節點感興趣的朋友，可以參考下這篇文章。本文基於之前網友對ShardedJedisPool的修改組件ShardedJedisSentinelPool進行優化，具體代碼，使用方式可參考如下。
// ShardedJedisSentinelPool.java
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.logging.Logger;
import java.util.regex.Pattern;
import org.apache.commons.pool2.PooledObject;
import org.apache.commons.pool2.PooledObjectFactory;
import org.apache.commons.pool2.impl.DefaultPooledObject;
import org.apache.commons.pool2.impl.GenericObjectPoolConfig;
import redis.clients.jedis.*;
import redis.clients.jedis.exceptions.JedisConnectionException;
import redis.clients.jedis.util.Hashing;
import redis.clients.jedis.util.Pool;
// 參考ShardedJedisPool實現的多master哨兵集羣組件
public class ShardedJedisSentinelPool extends Pool<ShardedJedis> {
private ShardedJedisPool mShardedJedisPool = null;
public static final int MAX_RETRY_SENTINEL = 10;
protected final Logger log = Logger.getLogger(getClass().getName());
protected GenericObjectPoolConfig poolConfig;
protected int timeout = Protocol.DEFAULT_TIMEOUT;
private int sentinelRetry = 0;
protected String password;
protected int database = Protocol.DEFAULT_DATABASE;
protected Set<MasterListener> masterListeners = new HashSet<MasterListener>();
private volatile List<HostAndPort> currentHostMasters;
public ShardedJedisSentinelPool(List<String> masters, Set<String> sentinels) {
this(masters, sentinels, new GenericObjectPoolConfig(),
Protocol.DEFAULT_TIMEOUT, null, Protocol.DEFAULT_DATABASE);
}
public ShardedJedisSentinelPool(List<String> masters, Set<String> sentinels, String password) {
this(masters, sentinels, new GenericObjectPoolConfig(),
Protocol.DEFAULT_TIMEOUT, password);
}
public ShardedJedisSentinelPool(final GenericObjectPoolConfig poolConfig, List<String> masters, Set<String> sentinels) {
this(masters, sentinels, poolConfig, Protocol.DEFAULT_TIMEOUT, null,
Protocol.DEFAULT_DATABASE);
}
public ShardedJedisSentinelPool(List<String> masters, Set<String> sentinels,
final GenericObjectPoolConfig poolConfig, int timeout,
final String password) {
this(masters, sentinels, poolConfig, timeout, password,
Protocol.DEFAULT_DATABASE);
}
public ShardedJedisSentinelPool(List<String> masters, Set<String> sentinels,
final GenericObjectPoolConfig poolConfig, final int timeout) {
this(masters, sentinels, poolConfig, timeout, null,
Protocol.DEFAULT_DATABASE);
}
public ShardedJedisSentinelPool(List<String> masters, Set<String> sentinels,
final GenericObjectPoolConfig poolConfig, final String password) {
this(masters, sentinels, poolConfig, Protocol.DEFAULT_TIMEOUT,
password);
}
public ShardedJedisSentinelPool(List<String> masters, Set<String> sentinels,
final GenericObjectPoolConfig poolConfig, int timeout,
final String password, final int database) {
this.poolConfig = poolConfig;
this.timeout = timeout;
this.password = password;
this.database = database;
List<HostAndPort> masterList = initSentinels(sentinels, masters);
initPool(masterList);
}
public void destroy() {
for (MasterListener m : masterListeners) {
m.shutdown();
}
super.destroy();
}
public List<HostAndPort> getCurrentHostMaster() {
return currentHostMasters;
}
private void initPool(List<HostAndPort> masters) {
if (!equals(currentHostMasters, masters)) {
StringBuffer sb = new StringBuffer();
for (HostAndPort master : masters) {
sb.append(master.toString());
sb.append(" ");
}
log.info("Created ShardedJedisPool to master at [" + sb.toString() + "]");
List<JedisShardInfo> shardMasters = makeShardInfoList(masters);
mShardedJedisPool = new ShardedJedisPool(poolConfig, shardMasters);
initPool(poolConfig, new ShardedJedisFactory(shardMasters, Hashing.MURMUR_HASH, null));
currentHostMasters = masters;
}
}
private boolean equals(List<HostAndPort> currentShardMasters, List<HostAndPort> shardMasters) {
if (currentShardMasters != null && shardMasters != null) {
if (currentShardMasters.size() == shardMasters.size()) {
for (int i = 0; i < currentShardMasters.size(); i++) {
if (!currentShardMasters.get(i).equals(shardMasters.get(i))) return false;
}
return true;
}
}
return false;
}
private List<JedisShardInfo> makeShardInfoList(List<HostAndPort> masters) {
List<JedisShardInfo> shardMasters = new ArrayList<JedisShardInfo>();
for (HostAndPort master : masters) {
JedisShardInfo jedisShardInfo = new JedisShardInfo(master.getHost(), master.getPort(), timeout);
jedisShardInfo.setPassword(password);
shardMasters.add(jedisShardInfo);
}
return shardMasters;
}
@Override
public ShardedJedis getResource() {
ShardedJedis jedis = mShardedJedisPool.getResource();
jedis.setDataSource(mShardedJedisPool);
return jedis;
}
@Override
public void returnResource(final ShardedJedis resource) {
if (resource != null) {
resource.resetState();
Class<?> classType = mShardedJedisPool.getClass();
try {
Method method = classType.getDeclaredMethod("returnResource",
ShardedJedis.class);
method.setAccessible(true);
method.invoke(mShardedJedisPool, resource);
} catch (IllegalAccessException e) {
log.severe(e.getMessage());
} catch (InvocationTargetException e) {
log.severe(e.getMessage());
} catch (NoSuchMethodException e) {
log.severe(e.getMessage());
}
}
}
public int getNumIdle() {
return mShardedJedisPool.getNumIdle();
}
public int getNumActive() {
return mShardedJedisPool.getNumActive();
}
@Override
public void returnBrokenResource(final ShardedJedis resource) {
if (resource != null) {
Class<?> classType = mShardedJedisPool.getClass();
try {
Method method = classType.getDeclaredMethod("returnBrokenResource",
ShardedJedis.class);
method.setAccessible(true);
method.invoke(mShardedJedisPool, resource);
} catch (IllegalAccessException e) {
log.severe(e.getMessage());
} catch (InvocationTargetException e) {
log.severe(e.getMessage());
} catch (NoSuchMethodException e) {
log.severe(e.getMessage());
}
}
}
private List<HostAndPort> initSentinels(Set<String> sentinels, final List<String> masters) {
Map<String, HostAndPort> masterMap = new HashMap<String, HostAndPort>();
List<HostAndPort> shardMasters = new ArrayList<HostAndPort>();
log.info("Trying to find all master from available Sentinels...");
for (String masterName : masters) {
HostAndPort master = null;
boolean fetched = false;
while (!fetched && sentinelRetry < MAX_RETRY_SENTINEL) {
for (String sentinel : sentinels) {
final HostAndPort hap = toHostAndPort(Arrays.asList(sentinel.split(":")));
log.fine("Connecting to Sentinel " + hap);
try {
Jedis jedis = new Jedis(hap.getHost(), hap.getPort());
master = masterMap.get(masterName);
if (master == null) {
List<String> hostAndPort = jedis.sentinelGetMasterAddrByName(masterName);
if (hostAndPort != null && hostAndPort.size() > 0) {
master = toHostAndPort(hostAndPort);
log.fine("Found Redis master at " + master);
shardMasters.add(master);
masterMap.put(masterName, master);
fetched = true;
jedis.disconnect();
break;
}
}
} catch (JedisConnectionException e) {
log.warning("Cannot connect to sentinel running @ " + hap + ". Trying next one.");
}
}
if (null == master) {
try {
log.severe("All sentinels down, cannot determine where is "
+ masterName + " master is running... sleeping 1000ms, Will try again.");
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
fetched = false;
sentinelRetry++;
}
}
// Try MAX_RETRY_SENTINEL times.
if (!fetched && sentinelRetry >= MAX_RETRY_SENTINEL) {
log.severe("All sentinels down and try " + MAX_RETRY_SENTINEL + " times, Abort.");
throw new JedisConnectionException("Cannot connect all sentinels, Abort.");
}
}
// All shards master must been accessed.
if (masters.size() != 0 && masters.size() == shardMasters.size()) {
log.info("Starting Sentinel listeners...");
for (String sentinel : sentinels) {
final HostAndPort hap = toHostAndPort(Arrays.asList(sentinel.split(":")));
MasterListener masterListener = new MasterListener(masters, hap.getHost(), hap.getPort());
masterListeners.add(masterListener);
masterListener.start();
}
}
return shardMasters;
}
private HostAndPort toHostAndPort(List<String> getMasterAddrByNameResult) {
String host = getMasterAddrByNameResult.get(0);
int port = Integer.parseInt(getMasterAddrByNameResult.get(1));
return new HostAndPort(host, port);
}
/**
* PoolableObjectFactory custom impl.
*/
protected static class ShardedJedisFactory implements PooledObjectFactory<ShardedJedis> {
private List<JedisShardInfo> shards;
private Hashing algo;
private Pattern keyTagPattern;
public ShardedJedisFactory(List<JedisShardInfo> shards, Hashing algo, Pattern keyTagPattern) {
this.shards = shards;
this.algo = algo;
this.keyTagPattern = keyTagPattern;
}
public PooledObject<ShardedJedis> makeObject() throws Exception {
ShardedJedis jedis = new ShardedJedis(shards, algo, keyTagPattern);
return new DefaultPooledObject<ShardedJedis>(jedis);
}
public void destroyObject(PooledObject<ShardedJedis> pooledShardedJedis) throws Exception {
final ShardedJedis shardedJedis = pooledShardedJedis.getObject();
for (Jedis jedis : shardedJedis.getAllShards()) {
try {
try {
jedis.quit();
} catch (Exception e) {
}
jedis.disconnect();
} catch (Exception e) {
}
}
}
public boolean validateObject(PooledObject<ShardedJedis> pooledShardedJedis) {
try {
ShardedJedis jedis = pooledShardedJedis.getObject();
for (Jedis shard : jedis.getAllShards()) {
if (!shard.ping().equals("PONG")) {
return false;
}
}
return true;
} catch (Exception ex) {
return false;
}
}
public void activateObject(PooledObject<ShardedJedis> p) throws Exception {
}
public void passivateObject(PooledObject<ShardedJedis> p) throws Exception {
}
}
protected class JedisPubSubAdapter extends JedisPubSub {
@Override
public void onMessage(String channel, String message) {
}
@Override
public void onPMessage(String pattern, String channel, String message) {
}
@Override
public void onPSubscribe(String pattern, int subscribedChannels) {
}
@Override
public void onPUnsubscribe(String pattern, int subscribedChannels) {
}
@Override
public void onSubscribe(String channel, int subscribedChannels) {
}
@Override
public void onUnsubscribe(String channel, int subscribedChannels) {
}
}
protected class MasterListener extends Thread {
protected List<String> masters;
protected String host;
protected int port;
protected long subscribeRetryWaitTimeMillis = 5000;
protected Jedis jedis;
protected AtomicBoolean running = new AtomicBoolean(false);
protected MasterListener() {
}
public MasterListener(List<String> masters, String host, int port) {
this.masters = masters;
this.host = host;
this.port = port;
}
public MasterListener(List<String> masters, String host, int port,
long subscribeRetryWaitTimeMillis) {
this(masters, host, port);
this.subscribeRetryWaitTimeMillis = subscribeRetryWaitTimeMillis;
}
public void run() {
running.set(true);
while (running.get()) {
jedis = new Jedis(host, port);
try {
jedis.subscribe(new JedisPubSubAdapter() {
@Override
public void onMessage(String channel, String message) {
log.info("Sentinel " + host + ":" + port + " published: " + message + ".");
String[] switchMasterMsg = message.split(" ");
if (switchMasterMsg.length > 3) {
int index = masters.indexOf(switchMasterMsg[0]);
if (index >= 0) {
HostAndPort newHostMaster = toHostAndPort(Arrays.asList(switchMasterMsg[3], switchMasterMsg[4]));
List<HostAndPort> newHostMasters = new ArrayList<HostAndPort>();
for (int i = 0; i < masters.size(); i++) {
newHostMasters.add(null);
}
Collections.copy(newHostMasters, currentHostMasters);
newHostMasters.set(index, newHostMaster);
initPool(newHostMasters);
} else {
StringBuffer sb = new StringBuffer();
for (String masterName : masters) {
sb.append(masterName);
sb.append(",");
}
log.fine("Ignoring message on +switch-master for master name "
+ switchMasterMsg[0]
+ ", our monitor master name are ["
+ sb + "]");
}
} else {
log.severe("Invalid message received on Sentinel "
+ host
+ ":"
+ port
+ " on channel +switch-master: "
+ message);
}
}
}, "+switch-master");
} catch (JedisConnectionException e) {
if (running.get()) {
log.severe("Lost connection to Sentinel at " + host
+ ":" + port
+ ". Sleeping 5000ms and retrying.");
try {
Thread.sleep(subscribeRetryWaitTimeMillis);
} catch (InterruptedException e1) {
e1.printStackTrace();
}
} else {
log.fine("Unsubscribing from Sentinel at " + host + ":"
+ port);
}
}
}
}
public void shutdown() {
try {
log.fine("Shutting down listener on " + host + ":" + port);
running.set(false);
// This isn't good, the Jedis object is not thread safe
jedis.disconnect();
} catch (Exception e) {
log.severe("Caught exception while shutting down: " + e.getMessage());
}
}
}
}
具體使用，針對2個Master節點，3個Sentinel節點，每個Master節點有2個Slave節點，使用方式如下：
static ShardedJedisSentinelPool pool = initShardedSentinelPool();
public static ShardedJedisSentinelPool initShardedSentinelPool() {
GenericObjectPoolConfig config = new GenericObjectPoolConfig();
config.setMaxTotal(100);
config.setMaxIdle(10);
String password = "myredis";
List<String> masters = new ArrayList<String>();
masters.add("mymaster");//sentinel 模式Redis主節點的別名
masters.add("mymastera");
Set<String> sentinels = new HashSet<String>();
sentinels.add("192.168.0.57:26379");
sentinels.add("192.168.0.58:26379");
sentinels.add("192.168.0.59:26379");
ShardedJedisSentinelPool pool = new ShardedJedisSentinelPool(masters, sentinels, config, 60000, password);
return pool;
}
public static void main(String[] args) {
ShardedJedisSentinelPool pool = initShardedSentinelPool();
redisNodeTestHash(pool);
}
public static void redisNodeTestHash(ShardedJedisSentinelPool pool) {
// 獲取客戶端
ShardedJedis jedis = pool.getResource();
int active = pool.getNumActive();
int idle = pool.getNumIdle();
System.out.println("redisNodeSwitch pool active " + active + " idle " + idle);
try {
ShardedJedisPipeline p = jedis.pipelined();
for( int i = 0; i < 300000; i++ ){
p.set("keynum" + i, CommonTools.getRandomString(64));
}
// p.syncAndReturnAll();
p.sync();
} catch (Exception e) {
e.printStackTrace();
pool.returnBrokenResource(jedis);
}finally {
pool.returnResource(jedis);
}
System.out.println("redisNodeTestHash end ");
}