Flink Redis Sink 自定义

背景

Flink 默认的 RedisMapper 不能设置key的过期时间。

依赖

<dependency>
    <groupId>redis.clients</groupId>
    <artifactId>jedis</artifactId>
    <version>2.9.0</version>
</dependency>

SinkFunction & RichSinkFunction

image
image
image
image

Demo

package com.yljphp.demo.sink

import org.apache.flink.configuration.Configuration
import org.apache.flink.streaming.api.functions.sink.{RichSinkFunction, SinkFunction}
import org.apache.flink.streaming.api.scala._
import org.apache.flink.util.StringUtils
import redis.clients.jedis.Jedis

object RedisCustomSink extends App {

  val env = StreamExecutionEnvironment.getExecutionEnvironment

  env.setParallelism(1)

  val text: DataStream[String] = env.socketTextStream("localhost", 9000)

  val data = text.filter(!StringUtils.isNullOrWhitespaceOnly(_))
    .flatMap(_.split(","))
    .map(MySaveInfo("RedisCustomSink", _))


  data.addSink(new CustomSinkToRedis)

  env.execute("sink_demo")
}

class CustomSinkToRedis extends RichSinkFunction[MySaveInfo] {

  var redisCon: Jedis = _

  override def open(parameters: Configuration): Unit = {
    super.open(parameters)
    this.redisCon = new Jedis("localhost", 6379)
  }

  override def close(): Unit = {
    super.close()
    if (this.redisCon != null) {
      this.redisCon.close()
    }
  }


  override def invoke(value: MySaveInfo, context: SinkFunction.Context[_]): Unit = {
    //super.invoke(value, context)
    println(value)
    println("sadd之前"+this.redisCon.ttl(value.key))
    this.redisCon.sadd(value.key, value.value)
    println("sadd之后"+this.redisCon.ttl(value.key))
    if (this.redisCon.ttl(value.key) == -1) {
      this.redisCon.expire(value.key, 60 * 60)
    }
    println("设置过期之后/每次更新后"+this.redisCon.ttl(value.key))
  }

}

case class MySaveInfo(key: String, value: String)

socket窗口输入123,345,234,123

image image image

参考

如何自定义 Data Sink