Cluster Execution

Flink programs can run distributed on clusters of many machines. There are two ways to send a program to a cluster for execution:

Command Line Interface

The command line interface lets you submit packaged programs (JARs) to a cluster (or single machine setup).

Please refer to the Command Line Interface documentation for details.

Remote Environment

The remote environment lets you execute Flink Java programs on a cluster directly. The remote environment points to the cluster on which you want to execute the program.

Maven Dependency

If you are developing your program as a Maven project, you have to add the flink-clients module using this dependency:

<dependency>
  <groupId>org.apache.flink</groupId>
  <artifactId>flink-clients_2.10</artifactId>
  <version>1.2.1</version>
</dependency>

Example

The following illustrates the use of the RemoteEnvironment:

public static void main(String[] args) throws Exception {
    ExecutionEnvironment env = ExecutionEnvironment
        .createRemoteEnvironment("flink-master", 6123, "/home/user/udfs.jar");

    DataSet<String> data = env.readTextFile("hdfs://path/to/file");

    data
        .filter(new FilterFunction<String>() {
            public boolean filter(String value) {
                return value.startsWith("http://");
            }
        })
        .writeAsText("hdfs://path/to/result");

    env.execute();
}

Note that the program contains custom user code and hence requires a JAR file with the classes of the code attached. The constructor of the remote environment takes the path(s) to the JAR file(s).