Java 数据流之Broadcast State

package cn.kgc.broadcast
 
import java.sql.{Connection, DriverManager, PreparedStatement}
 
import com.alibaba.fastjson.JSON
import org.apache.flink.api.common.state.{BroadcastState, MapStateDescriptor}
import org.apache.flink.configuration.Configuration
import org.apache.flink.streaming.api.datastream.BroadcastStream
import org.apache.flink.streaming.api.functions.co.BroadcastProcessFunction
import org.apache.flink.streaming.api.functions.source.{RichParallelSourceFunction, SourceFunction}
import org.apache.flink.streaming.api.scala._
import org.apache.flink.util.Collector
 
// (001,"tom",18,"北京",15830010002)
// 定义样例类 接受 MySQL的用户数据
case class BaseUserInfo(id:Long,name:String,age:Int,city:String,phone:Long)
 
// user_id、user_name、user_addrss、behaviour、url
// 输出数据类型
case class UserVisitInfo(id:Long,name:String,city:String,behaviour:String,url:String)
 
// 实现广播ProcessFunction
class MyBroadcastFunc extends BroadcastProcessFunction[String,(Long, BaseUserInfo),UserVisitInfo]{
 
  lazy val mapStateDes = new MapStateDescriptor[Long, BaseUserInfo]("mapState",classOf[Long],classOf[BaseUserInfo])
 
  // 处理的是日志流中的每条数据
  override def processElement(value: String, ctx: BroadcastProcessFunction[String, (Long, BaseUserInfo), UserVisitInfo]#ReadOnlyContext, out: Collector[UserVisitInfo]): Unit = {
    // {"user_id":"001","ts":"2021-07-10 11:10:05","behaviour":"browse","url":"https://www.tb1.com/1.html"}
    val user_id = JSON.parseObject(value).getLong("user_id")
    val behaviour = JSON.parseObject(value).getString("behaviour")
    val url = JSON.parseObject(value).getString("url")
 
    val mapState = ctx.getBroadcastState(mapStateDes)
    val userInfo = mapState.get(user_id)
 
    out.collect(UserVisitInfo(user_id,userInfo.name,userInfo.city,behaviour,url))
 
  }
 
  // 处理的是广播流的每个值
  override def processBroadcastElement(value: (Long, BaseUserInfo), ctx: BroadcastProcessFunction[String, (Long, BaseUserInfo), UserVisitInfo]#Context, out: Collector[UserVisitInfo]): Unit = {
    val mapState: BroadcastState[Long, BaseUserInfo] = ctx.getBroadcastState(mapStateDes)
    mapState.put(value._1,value._2)
  }
}
 
 
class UserSourceFunc extends RichParallelSourceFunction[BaseUserInfo]{
 
  var conn:Connection = _
  var statement: PreparedStatement = _
  var flag:Boolean = true
 
  override def open(parameters: Configuration): Unit = {
    conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test?characterEncoding=utf-8&serverTimezone=UTC","root","liu911223")
    statement = conn.prepareStatement("select * from base_user")
  }
 
  override def run(ctx: SourceFunction.SourceContext[BaseUserInfo]): Unit = {
    while (flag){
      Thread.sleep(5000)
      val resultSet = statement.executeQuery()
      while (resultSet.next()){
        val id = resultSet.getLong(1)
        val name = resultSet.getString(2)
        val age = resultSet.getInt(3)
        val city = resultSet.getString(4)
        val phone = resultSet.getLong(5)
        ctx.collect(BaseUserInfo(id,name,age,city,phone))
      }
    }
  }
 
  override def cancel(): Unit = {
    flag = false
  }
 
  override def close(): Unit = {
    if (statement != null) statement.close()
    if (conn != null) conn.close()
  }
}
object BroadcastDemo01 {
  def main(args: Array[String]): Unit = {
    val env = StreamExecutionEnvironment.getExecutionEnvironment
    env.setParallelism(1)
 
    // 定义为KV，一方面是为了广播的时候定义为map，另一方面是为了做关联操作
    val userBaseDS: DataStream[(Long, BaseUserInfo)] = env.addSource(new UserSourceFunc)
      .map(user => (user.id, user))
    val mapStateDes = new MapStateDescriptor[Long, BaseUserInfo]("mapState",classOf[Long],classOf[BaseUserInfo])
    val broadCastStream: BroadcastStream[(Long, BaseUserInfo)] = userBaseDS.broadcast(mapStateDes)
 
    // 日志JSON数据
    val dataInfoDS: DataStream[String] = env.socketTextStream("master",1314)
 
    dataInfoDS.connect(broadCastStream)
      .process(new MyBroadcastFunc)
      .print()
 
    env.execute()
  }
}