Apache Flink 入门

官网链接

https://flink.apache.org/

下载安装部署单机版

1. 进入主页点击downloads,选择你想要的版本
   

2.选择整合或者不整合hadoop的版本

3. 下载

4. 上传下载的压缩包到虚拟机，并解压

5. 在解压目录下面bin/ 执行命令 ./start-cluster.sh 即可， 同理停止集群 ./stop-cluster.sh
   

6. web页面查看 *****:8081
   

7. 提交任务
   

8. 查看提交的任务状态
   
   
9. 大工告成， 快动手写demo吧。

DEMO

<!-- pom依赖 -->

  <dependencies>
    <dependency>
      <groupId>org.apache.flink</groupId>
      <artifactId>flink-scala_2.11</artifactId>
      <version>1.7.2</version>
    </dependency>
    <dependency>
      <groupId>org.apache.flink</groupId>
      <artifactId>flink-streaming-scala_2.11</artifactId>
      <version>1.7.2</version>
    </dependency>

    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.11</version>
      <scope>test</scope>
    </dependency>

    <dependency>
      <groupId>org.scala-lang</groupId>
      <artifactId>scala-library</artifactId>
      <version>2.11.12</version>
    </dependency>
    <dependency>
      <groupId>org.scala-lang.modules</groupId>
      <artifactId>scala-xml_2.11</artifactId>
      <version>1.0.1</version>
    </dependency>
    <!--entity-->
    <dependency>
      <groupId>org.projectlombok</groupId>
      <artifactId>lombok</artifactId>
      <version>1.18.8</version>
      <scope>provided</scope>
    </dependency>

  </dependencies>


/**
 * 代码
 * 将项目打包  上传即可。
 */
object StreamWC {

  def main(args: Array[String]): Unit = {
    val environment = StreamExecutionEnvironment.getExecutionEnvironment

    val words = environment.socketTextStream("localhost", 7777)

    val unit = words.flatMap(_.split("\t"))
      .map((_, 1))
      .keyBy(0)
    unit.print()
    
    // 设置并行度
    environment.setParallelism(2)

    environment.execute("test stream flink")
    
  }
}

常见问题汇总

1. 分配资源不够

org.apache.flink.runtime.jobmanager.scheduler.NoResourceAvailableException: Could not allocate all requires slots within timeout of 300000 ms. Slots required: 9, slots allocated: 2

2.