Flink实例二: 自定义source

1 工程目录

SensorReading

package com.atguigu.flink.bean

case class SensorReading(
                          id: String,
                          timestamp: Long,
                          timepreture: Double
                        )

SensorSource

package com.atguigu.flink.source

import java.util.Calendar

import com.atguigu.flink.bean.SensorReading
import org.apache.flink.streaming.api.functions.source.{RichParallelSourceFunction, RichSourceFunction, SourceFunction}

import scala.collection.immutable
import scala.util.Random

class SensorSource extends RichSourceFunction[SensorReading]{
  //表示数据源是否运行正常
  var running: Boolean = true

  //上下文参数来发送数据
  override def run(sContext:SourceFunction.sourceContext[SensorReading]) {
    val rand = new Random()
    //使用高斯噪声产生随机温度
    val curftemp = (1 to 10).map(
      i => ("sensor_" + i, rand.nextGaussian() * 20)
    )

  //产生无限流数据
    while(running){
      val mapTemp:immutable.IndexedSeq[(String,Double)] = curftemp.map(
        t => (t._1,t._2 + (rand.nextGaussian()*10))
      )
      //产生时间戳
      val curTime:Long = Calendar.getInstance().getTimeInMillis

      //发送出去
      mapTemp.foreach(t => sContext.collect(SensorReading(t._1,curTime,t._2)))
      //每隔100ms发送一条传感器数据
      Thread.sleep(100)

    }

  }
  override def cancel(): Unit = running =false
}

主程序入口 ConsumerFromSensorSource

package com.atguigu.flink.app

import com.atguigu.flink.bean.SensorReading
import com.atguigu.flink.source.SensorSource
import org.apache.flink.streaming.api.datastream.DataStreamSource
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment

object ConsumerFromSensorSource {
  def main(args: Array[String]): Unit = {
    val env: StreamExecutionEnvironment = StreamExecutionEnvironment.getExecutionEnvironment
    env.setParallelism(1)

    //调用addSource
    val stream: DataStreamSource[SensorReading] = env.addSource(new SensorSource)

    // 打印流
    stream.print()

    // 执行主程序
    env.execute()



  }

}