content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.beam.runners.flink;
  
  import org.apache.flink.configuration.Configuration;
  import org.apache.flink.configuration.RestOptions;
  import org.apache.flink.runtime.minicluster.MiniCluster;
  import org.apache.flink.runtime.minicluster.MiniClusterConfiguration;
  import org.kohsuke.args4j.CmdLineException;
  import org.kohsuke.args4j.CmdLineParser;
  import org.kohsuke.args4j.Option;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /** Entry point for starting an embedded Flink cluster. */
  public class FlinkMiniClusterEntryPoint {
  
    private static final Logger LOG = LoggerFactory.getLogger(FlinkMiniClusterEntryPoint.class);
  
    static class MiniClusterArgs {
      @Option(name = "--rest-port")
      int restPort = 0;
  
      @Option(name = "--rest-bind-address")
      String restBindAddress = "";
  
      @Option(name = "--num-task-managers")
      int numTaskManagers = 1;
  
      @Option(name = "--num-task-slots-per-taskmanager")
      int numSlotsPerTaskManager = 1;
    }
  
    public static void main(String[] args) throws Exception {
      MiniClusterArgs miniClusterArgs = parseArgs(args);
  
      Configuration flinkConfig = new Configuration();
      flinkConfig.setInteger(RestOptions.PORT, miniClusterArgs.restPort);
      if (!miniClusterArgs.restBindAddress.isEmpty()) {
        flinkConfig.setString(RestOptions.BIND_ADDRESS, miniClusterArgs.restBindAddress);
      }
  
      MiniClusterConfiguration clusterConfig =
          new MiniClusterConfiguration.Builder()
              .setConfiguration(flinkConfig)
              .setNumTaskManagers(miniClusterArgs.numTaskManagers)
              .setNumSlotsPerTaskManager(miniClusterArgs.numSlotsPerTaskManager)
              .build();
  
      try (MiniCluster miniCluster = new MiniCluster(clusterConfig)) {
        miniCluster.start();
        System.out.println(
            String.format(
                "Started Flink mini cluster (%s TaskManagers with %s task slots) with Rest API at %s",
                miniClusterArgs.numTaskManagers,
                miniClusterArgs.numSlotsPerTaskManager,
                miniCluster.getRestAddress()));
        Thread.sleep(Long.MAX_VALUE);
      }
    }
  
    private static MiniClusterArgs parseArgs(String[] args) {
      MiniClusterArgs configuration = new MiniClusterArgs();
      CmdLineParser parser = new CmdLineParser(configuration);
      try {
        parser.parseArgument(args);
      } catch (CmdLineException e) {
        LOG.error("Unable to parse command line arguments.", e);
        printUsage(parser);
        throw new IllegalArgumentException("Unable to parse command line arguments.", e);
      }
      return configuration;
    }
  
    private static void printUsage(CmdLineParser parser) {
      System.err.println(
          String.format(
              "Usage: java %s arguments...", FlinkMiniClusterEntryPoint.class.getSimpleName()));
      parser.printUsage(System.err);
      System.err.println();
    }
  }
  