Flink寫入Redis集群重寫flink-connector-redis包

使用flink的時候難免和redis打交道，相信大家都使用過flink-connector-redis來處理，但是當我想要使用RedisSink寫入集群時，發現居然不支持使用密碼，於是有了這篇筆記。 ...

起因：使用flink的時候難免和redis打交道，相信大家都使用過flink-connector-redis來處理，但是當我想要使用RedisSink寫入集群時，發現居然不支持使用密碼，於是有了這篇筆記。

事情的經過是這樣的，我準備用Flink往Redis寫入數據，我照常引入flink-connector-redis包

        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-connector-redis_2.11</artifactId>
            <version>1.1.5</version>
        </dependency>

然後洋洋灑灑寫下如下代碼：

package org.cube.flink

import org.apache.flink.streaming.api.scala.StreamExecutionEnvironment
import org.apache.flink.streaming.connectors.redis.RedisSink
import org.apache.flink.streaming.connectors.redis.common.config.FlinkJedisPoolConfig
import org.apache.flink.streaming.connectors.redis.common.mapper.{RedisCommand, RedisCommandDescription, RedisMapper}

import java.net.InetSocketAddress
import java.util.HashSet

/**
 * @Author : Lawrence
 * @Date : 2022/7/24 23:11
 * @Description : Flink結果寫入Redis集群
 * @Version : 1.0.0
 * @Modification_Record:
 * Version  Date       Remark
 * v1.0.0   2022/7/24  First Create
 */
object RedisClusterSink {
  def main(args: Array[String]): Unit = {
    val env = StreamExecutionEnvironment.getExecutionEnvironment
    env.setParallelism(1)

    // source
    import org.apache.flink.api.scala._
    val source = env.fromElements("1 hadoop","2 spark","3 flink", "4 hive", "5 redis", "6 hbase")

    // process
    val tupleValue = source.map(_.split(" ")).map(x => (x(0), x(1)))

    // redis config
    val builder = new FlinkJedisPoolConfig.Builder
    builder.setHost("cube01").setPort(7001).setPassword("123456")
    val redisConf: FlinkJedisPoolConfig = builder.build()

    // sink
    val redisSink = new RedisSink[(String, String)](redisConf, new MyRedisMapper())

    tupleValue.addSink(redisSink)

    env.execute("RedisClusterSink")
  }
}

class MyRedisMapper extends RedisMapper[(String, String)] {
  override def getCommandDescription: RedisCommandDescription = {
    new RedisCommandDescription(RedisCommand.SET)
  }

  override def getKeyFromData(t: (String, String)): String = t._1

  override def getValueFromData(t: (String, String)): String = t._2
}

然後興高采烈地點擊了運行，控制台卻給了我一抹中國紅，

其中最後一條是這樣說的：

Caused by: redis.clients.jedis.exceptions.JedisMovedDataException: MOVED 9842 192.168.20.132:7003

哦哦，是因為我的Redis是集群模式，

這並難不倒我，

我只需要把FlinkJedisPoolConfig改成FlinkJedisClusterConfig就萬事大吉了。

    // redis config
    val builder = new FlinkJedisClusterConfig.Builder
    val inetSocketAddress = new InetSocketAddress("cube01", 7001)
    val nodeSet = new HashSet[InetSocketAddress]()
    nodeSet.add(inetSocketAddress)
    builder.setNodes(nodeSet).setPassword("123456")
    val redisConf: FlinkJedisClusterConfig = builder.build()

可是，這個類並沒有setPassword方法，事實上它連"password"這個屬性都沒有。

這並難不倒我。

先不設密碼總行了吧？

燃鵝並不行，控制台又給了我一抹中國紅，

他是這樣說的：

Caused by: redis.clients.jedis.exceptions.JedisDataException: NOAUTH Authentication required.

呵呵，這可難不倒我，

我的本能反應是，應該到Maven倉庫中找到新版的flink-connector-redis包。

燃鵝，當我搜索之後發現，這已經是最新版了。

這也難不倒我。

FlinkJedisPoolConfig不是可以設置密碼嗎？

FlinkJedisClusterConfig不是可以訪問集群嗎？

如果我把他們兩個的代碼整合一下呢？是不是就好了。

於是我本能地把"FlinkJedisClusterConfig"改寫成了"MyFlinkJedisClusterConfig"類，增加了password屬性和對應的get，set方法。

package org.cube.flink;

/**
 * @Author : Lawrence
 * @Date : 2022/7/25 21:14
 * @Description : 包含了password的FlinkJedisClusterConfig
 * @Version : 1.0.0
 * @Modification_Record:
 * Version  Date       Remark
 * v1.0.0   2022/7/25  First Create
 */
import org.apache.commons.pool2.impl.GenericObjectPoolConfig;
import org.apache.flink.streaming.connectors.redis.common.config.FlinkJedisConfigBase;
import org.apache.flink.util.Preconditions;
import redis.clients.jedis.HostAndPort;
import redis.clients.jedis.Protocol;

import java.net.InetSocketAddress;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;

public class MyFlinkJedisClusterConfig extends FlinkJedisConfigBase {
    private static final long serialVersionUID = 1L;
    private final Set<InetSocketAddress> nodes;
    private final int maxRedirections;
    private int soTimeout;
    private String password;

    private MyFlinkJedisClusterConfig(Set<InetSocketAddress> nodes, int connectionTimeout, int soTimeout,
                                      int maxRedirections, int maxTotal, int maxIdle, int minIdle, String password) {
        super(connectionTimeout, maxTotal, maxIdle, minIdle);
        Preconditions.checkNotNull(nodes, "Node information should be presented");
        Preconditions.checkArgument(!nodes.isEmpty(), "Redis cluster hosts should not be empty");
        this.nodes = new HashSet(nodes);
        this.soTimeout = soTimeout;
        this.maxRedirections = maxRedirections;
        this.password = password;
    }

    public Set<HostAndPort> getNodes() {
        Set<HostAndPort> ret = new HashSet();
        Iterator var2 = this.nodes.iterator();

        while(var2.hasNext()) {
            InetSocketAddress node = (InetSocketAddress)var2.next();
            ret.add(new HostAndPort(node.getHostName(), node.getPort()));
        }

        return ret;
    }
    public int getMaxRedirections() {
        return this.maxRedirections;
    }
    public int getSoTimeout() { return this.soTimeout; }
    protected String getPassword() { return this.password; }

    public String toString() {
        return "JedisClusterConfig{nodes=" + this.nodes + ", timeout=" + this.connectionTimeout
                + ", maxRedirections=" + this.maxRedirections + ", maxTotal=" + this.maxTotal
                + ", maxIdle=" + this.maxIdle + ", minIdle=" + this.minIdle + '}';
    }

    public static class Builder {
        private Set<InetSocketAddress> nodes;
        private int timeout = Protocol.DEFAULT_TIMEOUT;
        private int maxRedirections = 5;
        //新增屬性
        private int soTimeout = Protocol.DEFAULT_TIMEOUT;
        private int maxTotal = GenericObjectPoolConfig.DEFAULT_MAX_TOTAL;
        private int maxIdle = GenericObjectPoolConfig.DEFAULT_MAX_IDLE;
        private int minIdle = GenericObjectPoolConfig.DEFAULT_MIN_IDLE;
        //增加的屬性
        private String password;

        public Builder() {
        }

        public MyFlinkJedisClusterConfig.Builder setNodes(Set<InetSocketAddress> nodes) {
            this.nodes = nodes;
            return this;
        }

        public MyFlinkJedisClusterConfig.Builder setTimeout(int timeout) {
            this.timeout = timeout;
            return this;
        }

        public MyFlinkJedisClusterConfig.Builder setSoTimeout(int soTimeout) {
            this.soTimeout = soTimeout;
            return this;
        }

        public MyFlinkJedisClusterConfig.Builder setMaxRedirections(int maxRedirections) {
            this.maxRedirections = maxRedirections;
            return this;
        }

        public MyFlinkJedisClusterConfig.Builder setMaxTotal(int maxTotal) {
            this.maxTotal = maxTotal;
            return this;
        }

        public MyFlinkJedisClusterConfig.Builder setMaxIdle(int maxIdle) {
            this.maxIdle = maxIdle;
            return this;
        }

        public MyFlinkJedisClusterConfig.Builder setMinIdle(int minIdle) {
            this.minIdle = minIdle;
            return this;
        }

        public MyFlinkJedisClusterConfig.Builder setPassword(String password) {
            this.password = password;
            return this;
        }

        public MyFlinkJedisClusterConfig build() {
            return new MyFlinkJedisClusterConfig(this.nodes, this.timeout, this.soTimeout,
                    this.maxRedirections, this.maxTotal, this.maxIdle, this.minIdle, this.password);
        }
    }
}

燃鵝，中國紅卻提醒我：

Caused by: java.lang.IllegalArgumentException: Jedis configuration not found

原來，Flink任務執行的時候會調用RedisSink中的open()方法：

    public void open(Configuration parameters) throws Exception {
        this.redisCommandsContainer = RedisCommandsContainerBuilder.build(this.flinkJedisConfigBase);
    }

而這個方法調用的"RedisCommandsContainerBuilder.build"方法，所使用的參數，依然是舊的FlinkJedisClusterConfig類：

    public static RedisCommandsContainer build(FlinkJedisConfigBase flinkJedisConfigBase)

所以，還得改寫這兩個類：

MyRedisSink：

package org.cube.flink;

/**
 * @Author : Lawrence
 * @Date : 2022/7/25 23:52
 * @Description :
 * @Version : 1.0.0
 * @Modification_Record :
 * Version  Date       Remark
 * v1.0.0   2022/7/25  First Create
 */
import org.apache.flink.configuration.Configuration;
import org.apache.flink.streaming.api.functions.sink.RichSinkFunction;
import org.apache.flink.streaming.connectors.redis.common.config.FlinkJedisConfigBase;
import org.apache.flink.streaming.connectors.redis.common.container.RedisCommandsContainer;
import org.apache.flink.streaming.connectors.redis.common.mapper.RedisCommand;
import org.apache.flink.streaming.connectors.redis.common.mapper.RedisCommandDescription;
import org.apache.flink.streaming.connectors.redis.common.mapper.RedisMapper;
import org.apache.flink.util.Preconditions;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;

public class MyRedisSink<IN> extends RichSinkFunction<IN> {
    private static final long serialVersionUID = 1L;
    private static final Logger LOG = LoggerFactory.getLogger(org.apache.flink.streaming.connectors.redis.RedisSink.class);
    private String additionalKey;
    private RedisMapper<IN> redisSinkMapper;
    private RedisCommand redisCommand;
    private FlinkJedisConfigBase flinkJedisConfigBase;
    private RedisCommandsContainer redisCommandsContainer;

    public MyRedisSink(FlinkJedisConfigBase flinkJedisConfigBase, RedisMapper<IN> redisSinkMapper) {
        Preconditions.checkNotNull(flinkJedisConfigBase, "Redis connection pool config should not be null");
        Preconditions.checkNotNull(redisSinkMapper, "Redis Mapper can not be null");
        Preconditions.checkNotNull(redisSinkMapper.getCommandDescription(), "Redis Mapper data type description can not be null");
        this.flinkJedisConfigBase = flinkJedisConfigBase;
        this.redisSinkMapper = redisSinkMapper;
        RedisCommandDescription redisCommandDescription = redisSinkMapper.getCommandDescription();
        this.redisCommand = redisCommandDescription.getCommand();
        this.additionalKey = redisCommandDescription.getAdditionalKey();
    }

    @Override
    public void invoke(IN input) throws Exception {
        String key = this.redisSinkMapper.getKeyFromData(input);
        String value = this.redisSinkMapper.getValueFromData(input);
        switch(this.redisCommand) {
            case RPUSH:
                this.redisCommandsContainer.rpush(key, value);
                break;
            case LPUSH:
                this.redisCommandsContainer.lpush(key, value);
                break;
            case SADD:
                this.redisCommandsContainer.sadd(key, value);
                break;
            case SET:
                this.redisCommandsContainer.set(key, value);
                break;
            case PFADD:
                this.redisCommandsContainer.pfadd(key, value);
                break;
            case PUBLISH:
                this.redisCommandsContainer.publish(key, value);
                break;
            case ZADD:
                this.redisCommandsContainer.zadd(this.additionalKey, value, key);
                break;
            case HSET:
                this.redisCommandsContainer.hset(this.additionalKey, key, value);
                break;
            default:
                throw new IllegalArgumentException("Cannot process such data type: " + this.redisCommand);
        }

    }

    @Override
    public void open(Configuration parameters) throws Exception {
        this.redisCommandsContainer = MyRedisCommandsContainerBuilder.build(this.flinkJedisConfigBase);
    }

    @Override
    public void close() throws IOException {
        if (this.redisCommandsContainer != null) {
            this.redisCommandsContainer.close();
        }

    }
}

MyRedisCommandsContainerBuilder：

package org.cube.flink;

/**
 * @Author : Lawrence
 * @Date : 2022/7/25 21:30
 * @Description : 包含了password的RedisCommandsContainerBuilder
 * @Version : 1.0.0
 * @Modification_Record :
 * Version  Date       Remark
 * v1.0.0   2022/7/25  First Create
 */
import org.apache.commons.pool2.impl.GenericObjectPoolConfig;
import org.apache.flink.streaming.connectors.redis.common.config.FlinkJedisConfigBase;
import org.apache.flink.streaming.connectors.redis.common.config.FlinkJedisPoolConfig;
import org.apache.flink.streaming.connectors.redis.common.config.FlinkJedisSentinelConfig;
import org.apache.flink.streaming.connectors.redis.common.container.RedisClusterContainer;
import org.apache.flink.streaming.connectors.redis.common.container.RedisCommandsContainer;
import org.apache.flink.streaming.connectors.redis.common.container.RedisContainer;
import org.apache.flink.util.Preconditions;
import redis.clients.jedis.JedisCluster;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisSentinelPool;

public class MyRedisCommandsContainerBuilder {
    public MyRedisCommandsContainerBuilder() {
    }

    public static RedisCommandsContainer build(FlinkJedisConfigBase flinkJedisConfigBase) {
        if (flinkJedisConfigBase instanceof FlinkJedisPoolConfig) {
            FlinkJedisPoolConfig flinkJedisPoolConfig = (FlinkJedisPoolConfig)flinkJedisConfigBase;
            return build(flinkJedisPoolConfig);
        } else if (flinkJedisConfigBase instanceof MyFlinkJedisClusterConfig) {
            MyFlinkJedisClusterConfig flinkJedisClusterConfig = (MyFlinkJedisClusterConfig)flinkJedisConfigBase;
            return build(flinkJedisClusterConfig);
        } else if (flinkJedisConfigBase instanceof FlinkJedisSentinelConfig) {
            FlinkJedisSentinelConfig flinkJedisSentinelConfig = (FlinkJedisSentinelConfig)flinkJedisConfigBase;
            return build(flinkJedisSentinelConfig);
        } else {
            throw new IllegalArgumentException("Jedis configuration not found");
        }
    }

    public static RedisCommandsContainer build(FlinkJedisPoolConfig jedisPoolConfig) {
        Preconditions.checkNotNull(jedisPoolConfig, "Redis pool config should not be Null");
        GenericObjectPoolConfig genericObjectPoolConfig = new GenericObjectPoolConfig();
        genericObjectPoolConfig.setMaxIdle(jedisPoolConfig.getMaxIdle());
        genericObjectPoolConfig.setMaxTotal(jedisPoolConfig.getMaxTotal());
        genericObjectPoolConfig.setMinIdle(jedisPoolConfig.getMinIdle());
        JedisPool jedisPool = new JedisPool(genericObjectPoolConfig, jedisPoolConfig.getHost(), jedisPoolConfig.getPort()
                , jedisPoolConfig.getConnectionTimeout(), jedisPoolConfig.getPassword(), jedisPoolConfig.getDatabase());
        return new RedisContainer(jedisPool);
    }

    public static RedisCommandsContainer build(MyFlinkJedisClusterConfig jedisClusterConfig) {
        Preconditions.checkNotNull(jedisClusterConfig, "Redis cluster config should not be Null");
        GenericObjectPoolConfig genericObjectPoolConfig = new GenericObjectPoolConfig();
        genericObjectPoolConfig.setMaxIdle(jedisClusterConfig.getMaxIdle());
        genericObjectPoolConfig.setMaxTotal(jedisClusterConfig.getMaxTotal());
        genericObjectPoolConfig.setMinIdle(jedisClusterConfig.getMinIdle());
        JedisCluster jedisCluster;
        if (null == jedisClusterConfig.getPassword()) {
            jedisCluster = new JedisCluster(jedisClusterConfig.getNodes(), jedisClusterConfig.getConnectionTimeout(), 
                    jedisClusterConfig.getMaxRedirections(), genericObjectPoolConfig);
        } else
            {
            jedisCluster = new JedisCluster(jedisClusterConfig.getNodes(), jedisClusterConfig.getConnectionTimeout()
                    , jedisClusterConfig.getSoTimeout(), jedisClusterConfig.getMaxRedirections()
                    , jedisClusterConfig.getPassword(), genericObjectPoolConfig);
        }
        return new RedisClusterContainer(jedisCluster);
    }

    public static RedisCommandsContainer build(FlinkJedisSentinelConfig jedisSentinelConfig) {
        Preconditions.checkNotNull(jedisSentinelConfig, "Redis sentinel config should not be Null");
        GenericObjectPoolConfig genericObjectPoolConfig = new GenericObjectPoolConfig();
        genericObjectPoolConfig.setMaxIdle(jedisSentinelConfig.getMaxIdle());
        genericObjectPoolConfig.setMaxTotal(jedisSentinelConfig.getMaxTotal());
        genericObjectPoolConfig.setMinIdle(jedisSentinelConfig.getMinIdle());
        JedisSentinelPool jedisSentinelPool = new JedisSentinelPool(jedisSentinelConfig.getMasterName()
                , jedisSentinelConfig.getSentinels(), genericObjectPoolConfig, jedisSentinelConfig.getConnectionTimeout()
                , jedisSentinelConfig.getSoTimeout(), jedisSentinelConfig.getPassword(), jedisSentinelConfig.getDatabase());
        return new RedisContainer(jedisSentinelPool);
    }
}

燃鵝，在重寫"MyRedisCommandsContainerBuilder"類時，你會驚奇地發現，jedisCluster 也不支持密碼。

你可千萬別慣性思維去重新jedisCluster ，

因為這回可真的是版本問題了。

所以這依然難不倒我，

只需要把redis.clients包升級到2.9以上版本即可：

        <dependency>
            <groupId>redis.clients</groupId>
            <artifactId>jedis</artifactId>
            <version>2.9.1</version>
        </dependency>

        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-connector-redis_2.11</artifactId>
            <version>1.1.5</version>
            <exclusions>
                <exclusion>
                    <groupId>redis.clients</groupId>
                    <artifactId>jedis</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

好了，到這裡咱們終於大功告成了。

代碼寫完了，但是咱們卻留下一個疑惑，

為什麼這麼簡單的需求卻沒有jar包更新呢？

我只是想把Flink數據寫到帶密碼的Redis集群里，這過分嗎？

這並不過分，那這又是為啥呢？

我想可能是這樣的：

首先，先想一個問題，在流計算中我們往Redis寫的是什麼數據？

通常是一些狀態信息，中間結果。而Flink本身支持狀態、緩存和廣播機制，導致對Redis的需求下降了。

其次，大數據應用實際運行的環境通常是提交到內網的機器上進行的，大家知道大數據集群之間的主機是需要設置免驗證登錄的，單單給Redis設密碼顯得有一點點多餘。

其三，Redis的密碼機制據說是很弱雞的，出於安全考慮，更多地是通過防火牆來限制埠，所以很多Redis集群處於管理方便並沒有設置密碼的。

其四，出於人類懶惰的本性，發現RedisSink不支持密碼後，最省事的方式，或許是放棄使用密碼。

好了該寫的寫了，該想的也想了，差不多可以愉快地結束這一天了。

那麼晚安了，咱們下期再肝。

Flink寫入Redis集群 重寫flink-connector-redis包

Flink寫入Redis集群重寫flink-connector-redis包