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.kafka.trogdor.fault;
  
  import org.apache.kafka.common.internals.KafkaFutureImpl;
  import org.apache.kafka.trogdor.common.Node;
  import org.apache.kafka.trogdor.common.Platform;
  import org.apache.kafka.trogdor.common.Topology;
  import org.apache.kafka.trogdor.task.TaskWorker;
  import org.apache.kafka.trogdor.task.WorkerStatusTracker;
  
  import com.fasterxml.jackson.databind.node.TextNode;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.net.InetAddress;
  import java.util.List;
  import java.util.Set;
  import java.util.TreeSet;
  
  public class NetworkPartitionFaultWorker implements TaskWorker {
      private static final Logger log = LoggerFactory.getLogger(NetworkPartitionFaultWorker.class);
  
      private final String id;
  
      private final List<Set<String>> partitionSets;
  
      private WorkerStatusTracker status;
  
      public NetworkPartitionFaultWorker(String id, List<Set<String>> partitionSets) {
          this.id = id;
          this.partitionSets = partitionSets;
      }
  
      @Override
      public void start(Platform platform, WorkerStatusTracker status,
                        KafkaFutureImpl<String> errorFuture) throws Exception {
          log.info("Activating NetworkPartitionFault {}.", id);
          this.status = status;
          this.status.update(new TextNode("creating network partition " + id));
          runIptablesCommands(platform, "-A");
          this.status.update(new TextNode("created network partition " + id));
      }
  
      @Override
      public void stop(Platform platform) throws Exception {
          log.info("Deactivating NetworkPartitionFault {}.", id);
          this.status.update(new TextNode("removing network partition " + id));
          runIptablesCommands(platform, "-D");
          this.status.update(new TextNode("removed network partition " + id));
      }
  
      private void runIptablesCommands(Platform platform, String iptablesAction) throws Exception {
          Node curNode = platform.curNode();
          Topology topology = platform.topology();
          TreeSet<String> toBlock = new TreeSet<>();
          for (Set<String> partitionSet : partitionSets) {
              if (!partitionSet.contains(curNode.name())) {
                  for (String nodeName : partitionSet) {
                      toBlock.add(nodeName);
                  }
              }
          }
          for (String nodeName : toBlock) {
              Node node = topology.node(nodeName);
              InetAddress addr = InetAddress.getByName(node.hostname());
              platform.runCommand(new String[] {
                  "sudo", "iptables", iptablesAction, "INPUT", "-p", "tcp", "-s",
                  addr.getHostAddress(), "-j", "DROP", "-m", "comment", "--comment", nodeName
              });
          }
      }
  }
  