Flink WC 案例

一、pom.xml

    <dependency>
      <groupId>org.apache.flink</groupId>
      <artifactId>flink-scala_2.11</artifactId>
      <version>${flink.version}</version>

    </dependency>
    <dependency>
      <groupId>org.apache.flink</groupId>
      <artifactId>flink-streaming-scala_2.11</artifactId>
      <version>${flink.version}</version>
    </dependency>

    <dependency>
      <groupId>org.apache.flink</groupId>
      <artifactId>flink-scala_2.11</artifactId>
      <version>${flink.version}</version>

    </dependency>
    <dependency>
      <groupId>org.apache.flink</groupId>
      <artifactId>flink-streaming-scala_2.11</artifactId>
      <version>${flink.version}</version>
    </dependency>

二、代码

package com.soul.flink

import org.apache.flink.api.java.utils.ParameterTool
import org.apache.flink.streaming.api.scala.StreamExecutionEnvironment
import org.apache.flink.streaming.api.scala._
import org.apache.flink.streaming.api.windowing.time.Time

/**
  * @author soulChun
  * @create 2019-06-30-23:20
  */
object SocketWindowWordCount {
  def main(args: Array[String]): Unit = {

    // the port to connect to
    val port: Int = try {
      ParameterTool.fromArgs(args).getInt("port")
    } catch {
      case e: Exception => {
        System.err.println("No port specified. Please run 'SocketWindowWordCount --port <port>'")
        return
      }
    }

    // get the execution environment
    val env = StreamExecutionEnvironment.getExecutionEnvironment

    // get input data by connecting to the socket
    val text = env.socketTextStream("hadoop000", port, '\n')

    // parse the data, group it, window it, and aggregate the counts
    val windowCounts = text
      .flatMap { w => w.split("\\s") }
      .map { w => WordWithCount(w, 1) }
      .keyBy("word")
      .timeWindow(Time.seconds(5), Time.seconds(1))
      .sum("count")

    // print the results with a single thread, rather than in parallel
    windowCounts.print().setParallelism(1)


    env.execute("Socket Window WordCount")



  }

  // Data type for words with count
  case class WordWithCount(word: String, count: Long)

}

三、测试

~/soul/app/flink-1.6.4 » start-cluster.sh

查看web正常打开hadoop000:8081

image.png

运行
启动nc

 nc -l 9000 

运行程序

 flink run -class com.soul.flink.SocketWindowWordCount /Users/mac/IdeaProjects/flink-train/target/flink-train-1.0.jar --port 9000

nc窗口输入值

» nc -l 9000                                                                                                   mac@hadoop000
spark   spark   spark
spark   spark   spark
hadoop  hadoop  hadoop    
a       a       a

查看结果

~/soul/app/flink-1.6.4 » tail -f log/flink-*-taskexecutor-*.out                                                  mac@hadoop000

==> log/flink-mac-taskexecutor-0-hadoop000.out <==
WordWithCount(spark,3)
WordWithCount(,4)
WordWithCount(,4)
WordWithCount(spark,3)
WordWithCount(spark,3)
WordWithCount(,4)
WordWithCount(,4)
WordWithCount(spark,3)
WordWithCount(spark,3)
WordWithCount(,4)

==> log/flink-mac-taskexecutor-1-hadoop000.out <==

==> log/flink-mac-taskexecutor-0-hadoop000.out <==
WordWithCount(hadoop,3)
WordWithCount(hadoop,3)
WordWithCount(hadoop,3)
WordWithCount(hadoop,3)
WordWithCount(hadoop,3)
WordWithCount(a,3)
WordWithCount(a,3)
WordWithCount(a,3)
WordWithCount(a,3)
WordWithCount(a,3)