content: /*
   * The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
   * (the "License"). You may not use this work except in compliance with the License, which is
   * available at www.apache.org/licenses/LICENSE-2.0
   *
   * This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
   * either express or implied, as more fully set forth in the License.
   *
   * See the NOTICE file distributed with this work for information regarding copyright ownership.
   */
  
  package alluxio.cli.extensions.command;
  
  import alluxio.Constants;
  import alluxio.cli.Command;
  import alluxio.cli.CommandUtils;
  import alluxio.conf.AlluxioConfiguration;
  import alluxio.conf.Configuration;
  import alluxio.conf.PropertyKey;
  import alluxio.exception.ExceptionMessage;
  import alluxio.exception.status.InvalidArgumentException;
  import alluxio.util.ConfigurationUtils;
  import alluxio.util.ShellUtils;
  import alluxio.util.io.PathUtils;
  
  import org.apache.commons.cli.CommandLine;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.List;
  import javax.annotation.concurrent.ThreadSafe;
  
  /**
   * Uninstall an extension.
   */
  @ThreadSafe
  public final class UninstallCommand implements Command {
    private static final Logger LOG = LoggerFactory.getLogger(UninstallCommand.class);
  
    /**
     * Constructs a new instance of {@link UninstallCommand}.
     */
    public UninstallCommand() {}
  
    @Override
    public String getCommandName() {
      return "uninstall";
    }
  
    @Override
    public String getUsage() {
      return "uninstall <JAR>";
    }
  
    @Override
    public String getDescription() {
      return "Uninstalls an extension from hosts configured in conf/masters and conf/workers.";
    }
  
    @Override
    public int run(CommandLine cl) {
      String uri = cl.getArgs()[0];
      AlluxioConfiguration conf = Configuration.global();
      String extensionsDir = conf.getString(PropertyKey.EXTENSIONS_DIR);
      List<String> failedHosts = new ArrayList<>();
      for (String host : ConfigurationUtils.getServerHostnames(conf)) {
        try {
          LOG.info("Attempting to uninstall extension on host {}", host);
          String rmCmd = String.format("ssh %s %s rm %s", ShellUtils.COMMON_SSH_OPTS, host,
              PathUtils.concatPath(extensionsDir, uri));
          LOG.debug("Executing: {}", rmCmd);
          String output = ShellUtils.execCommand("bash", "-c", rmCmd);
          LOG.debug("Succeeded w/ output: {}", output);
        } catch (IOException e) {
          LOG.error("Error uninstalling extension on host {}.", host, e);
          failedHosts.add(host);
        }
      }
      if (failedHosts.size() != 0) {
        System.err.println("Failed to uninstall extension on hosts:");
        for (String failedHost : failedHosts) {
          System.err.println(failedHost);
        }
        return -1;
      }
      System.out.println("Extension uninstalled successfully.");
      return 0;
    }
  
    @Override
    public void validateArgs(CommandLine cl) throws InvalidArgumentException {
      String[] args = cl.getArgs();
      CommandUtils.checkNumOfArgsEquals(this, cl, 1);
      if (args[0] == null) {
        throw new InvalidArgumentException(
            ExceptionMessage.INVALID_ARGS_NULL.getMessage(getCommandName()));
      }
      if (!args[0].endsWith(Constants.EXTENSION_JAR)) {
        throw new InvalidArgumentException(
            ExceptionMessage.INVALID_EXTENSION_NOT_JAR.getMessage(args[0]));
      }
    }
  }
  