RedisCluster 的 Java 和 Python 客户端 API 使用示例
这里的环境仍然采用 [Redis Cluster 的安装与配置] 中最终的集群配置环境，具体如下：
127.0.0.1:7000> cluster nodes 8868592d98d84b7cf5752cc0b97af4ac807d1a12 127.0.0.1:7007 slave bfc910f924d772fe03d9fe6a19aabd73d5730d26 0 1410882113063 8 connected f5bdda1518cd3826100a30f5953ed82a5861ed48 127.0.0.1:7002 slave bfc910f924d772fe03d9fe6a19aabd73d5730d26 0 1410882111659 8 connected 82578e8ec9747e46cbb4b8cc2484c71b9b2c91f4 127.0.0.1:7001 master - 0 1410882111158 2 connected 6461-10922 61dfb1055760d5dcf6519e35435d60dc5b207940 127.0.0.1:7004 slave 82578e8ec9747e46cbb4b8cc2484c71b9b2c91f4 0 1410882112662 5 connected 6d1ebedad33bb31ffbaa99bad095eef4a5920857 127.0.0.1:7006 master - 0 1410882111158 0 connected bfc910f924d772fe03d9fe6a19aabd73d5730d26 127.0.0.1:7005 master - 0 1410882111659 8 connected 11923-16383 35e0f6fdadbf81a00a1d6d1843698613e653867b 127.0.0.1:7003 slave 123ed65d59ff22370f2f09546f410d31207789f6 0 1410882110657 7 connected 123ed65d59ff22370f2f09546f410d31207789f6 127.0.0.1:7000 myself,master - 0 0 7 connected 0-6460 10923-11922 127.0.0.1:7000>
下面分别使用 Jedis 和 redis-py-cluster 来访问 cluster，操作主要有：set/get, pub/sub, 以及获取集群信息。
1，Jedis
从目前来看对于 redis 以及 RedisCluster 支持最好的应该只有 Jedis 这个开源项目了（也是Redis官网推荐的 Java 库），参考: https://github.com/xetorthio/jedis
import redis.clients.jedis.*;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
/**
* jedis 测试 cluster
*
* @author steven
*/
public class App
{
public static void main( String[] args )
{
Set<HostAndPort> clusterNodes = new HashSet<HostAndPort>();
// 这里只需要列出集群中的一个节点
// JedisCluster 会自己去 discovery 其他的集群节点
clusterNodes.add(new HostAndPort("127.0.0.1", 7000));
JedisCluster cluster = new JedisCluster(clusterNodes);
// set/get
cluster.set("foo", "jedis test");
String value = cluster.get("foo");
System.out.println("foo = " + value);
// get cluster nodes
System.out.println("------- cluster nodes --------");
Map<String, JedisPool> nodes = cluster.getClusterNodes();
Iterator<Map.Entry<String, JedisPool>> iterNodes = nodes.entrySet().iterator();
while (iterNodes.hasNext()) {
Map.Entry<String, JedisPool> entry = iterNodes.next();
Jedis jedis = entry.getValue().getResource();
System.out.println("============");
System.out.println(entry.getKey() + "\n" + jedis.info());
}
// pub/sub
System.out.println("------- pub/sub --------");
// 这里随机取了两个分别用于 publish 和 subscribe 的 jedis 连接
// Redis 不支持在同一个连接上既作为 publisher 又作为 subscriber
final JedisPool jedisPool = nodes.entrySet().iterator().next().getValue();
// 使用一个独立的线程来 publish
ExecutorService newFixedThreadPool = Executors.newFixedThreadPool(10);
newFixedThreadPool.submit(new Runnable() {
@Override
public void run() {
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
e.printStackTrace();
return ;
}
jedisPool.getResource().publish("channel-test", "hello, redis cluster!");
}
});
// subscribe - 此处会一直阻塞来接收 publish 消息
jedisPool.getResource().subscribe(new JedisPubSub() {
@Override
public void onMessage(String channel, String message) {
System.out.println("onMessage - " + channel + ":" + message);
}
@Override
public void onPMessage(String pattern, String channel, String message) {
System.out.println("onPMessage - " + pattern + "|" + channel + ":" + message);
}
@Override
public void onSubscribe(String channel, int subscribedChannels) {
System.out.println("onSubscribe - " + channel + ":" + subscribedChannels);
}
@Override
public void onUnsubscribe(String channel, int subscribedChannels) {
System.out.println("onUnsubscribe - " + channel + ":" + subscribedChannels);
}
@Override
public void onPUnsubscribe(String pattern, int subscribedChannels) {
System.out.println("onPUnsubscribe - " + pattern + ":" + subscribedChannels);
}
@Override
public void onPSubscribe(String pattern, int subscribedChannels) {
System.out.println("onPSubscribe - " + pattern + ":" + subscribedChannels);
}
}, "channel-test");
}
}
下面为 key 为 foo 的记录写入到了 7005 节点:
127.0.0.1:7000> get foo -> Redirected to slot [12182] located at 127.0.0.1:7005 "jedis test" 127.0.0.1:7005> keys foo 1) "foo" 127.0.0.1:7005>
2，redis-py-cluster
python 的 redis cluster 库采用的是 redis-py-cluster(https://github.com/Grokzen/redis-py-cluster)
下面代码只是演示使用 redis-py-cluster 的常见操作示例
如果需要查看 redis-py-cluster 的完整测试可以直接参考: https://github.com/Grokzen/redis-py-cluster/tree/master/tests
import redis
from rediscluster import RedisCluster
def main():
startup_nodes = [{"host": "127.0.0.1", "port": "7000"}]
rc = RedisCluster(startup_nodes=startup_nodes, decode_responses=True)
print '-------- get/set ---------'
if not rc.set("foo", "hello, redis-py-cluster"):
print 'set foo to cluster failed!!!'
return -1
print 'foo = %s' % (rc.get("foo"),)
if __name__ == '__main__':
main()