Example #1
0
def run():
    def main(args, opts):
        """Main"""
        server = RedirServer(opts.zk_basepath,
                             opts.subdomain,
                             opts.base_domain)
        thread = ExceptionalThread(
            target=lambda: server.run(opts.listen,
                                      opts.port,
                                      server='cherrypy'))
        thread.daemon = True
        thread.start()

        wait_forever()

    log.LogOptions.set_stderr_log_level('google:INFO')

    app.add_option('--port', help='http port', default=8080)
    app.add_option('--listen',
                   help='IP address to listen for http connections.',
                   default='0.0.0.0')
    app.add_option('--zk_basepath',
                   help='Zookeeper service path root.',
                   default='/aurora')
    app.add_option('--base_domain',
                   help='Domain name of your site.',
                   default='example.com')
    app.add_option('--subdomain',
                   help='Subdomain that roots Aurora job namespace.',
                   default='aurora')

    app.main()
def proxy_main():
  def main(args, opts):
    if args:
      print("ERROR: unrecognized arguments: %s\n" % (" ".join(args)), file=sys.stderr)
      app.help()
      sys.exit(1)

    root_server = HttpServer()
    root_server.mount_routes(DiagnosticsEndpoints())

    task_observer = TaskObserver(opts.root)
    task_observer.start()

    bottle_wrapper = BottleObserver(task_observer)

    root_server.mount_routes(bottle_wrapper)

    def run():
      root_server.run('0.0.0.0', opts.port, 'cherrypy')

    et = ExceptionalThread(target=run)
    et.daemon = True
    et.start()
    et.join()

  app.main()
Example #3
0
def proxy_main():
    """Proxy main function.

    setuptools entrypoints with twitter.common.app is so awkward.
    """
    def main(_, opts):
        """Main"""

        if not opts.bucket:
            log.error('--bucket is required.')
            app.help()

        server = S3Web(bucket=opts.bucket,
                       prefix=opts.prefix,
                       access_key_id=opts.access_key_id,
                       secret_key=opts.secret_key)
        thread = ExceptionalThread(
            target=lambda: server.run(opts.listen,
                                      opts.port,
                                      server='cherrypy'))
        thread.daemon = True
        thread.start()

        log.info('Ready.')
        app.wait_forever()

    register_opts()
    app.set_usage(__doc__)
    app.set_option('twitter_common_log_stderr_log_level', 'google:INFO')
    app.set_name('s3webfront')
    app.main()
def proxy_main():
  def main(args, options):
    thermos_runner_provider = DefaultThermosTaskRunnerProvider(
        dump_runner_pex(),
        artifact_dir=os.path.realpath('.'),
    )

    # status providers:
    status_providers = [HealthCheckerProvider()]

    if options.announcer_enable:
      if options.announcer_ensemble is None:
        app.error('Must specify --announcer-ensemble if the announcer is enabled.')
      status_providers.append(DefaultAnnouncerCheckerProvider(
          options.announcer_ensemble, options.announcer_serverset_path))

    # Create executor stub
    thermos_executor = AuroraExecutor(
        runner_provider=thermos_runner_provider,
        status_providers=status_providers,
    )

    # Create driver stub
    driver = MesosExecutorDriver(thermos_executor)

    # This is an ephemeral executor -- shutdown if we receive no tasks within a certain
    # time period
    ExecutorTimeout(thermos_executor.launched, driver).start()

    # Start executor
    driver.run()

    log.info('MesosExecutorDriver.run() has finished.')

  app.main()
def proxy_main():
  def main():
    runner_provider = DefaultThermosTaskRunnerProvider(
        dump_runner_pex(),
        artifact_dir=os.path.realpath('.'),
    )

    # Create executor stub
    thermos_executor = ThermosExecutor(
        runner_provider=runner_provider,
        status_providers=(HealthCheckerProvider(),),
    )

    # Create driver stub
    driver = mesos.MesosExecutorDriver(thermos_executor)

    # This is an ephemeral executor -- shutdown if we receive no tasks within a certain
    # time period
    ExecutorTimeout(thermos_executor.launched, driver).start()

    # Start executor
    driver.run()

    log.info('MesosExecutorDriver.run() has finished.')

  app.main()
Example #6
0
def proxy_main():
  def main(args, options):
    if MesosExecutorDriver is None:
      app.error('Could not load MesosExecutorDriver!')

    thermos_executor = initialize(options)

    # Create driver stub
    driver = MesosExecutorDriver(thermos_executor)

    # This is an ephemeral executor -- shutdown if we receive no tasks within a certain
    # time period
    ExecutorTimeout(thermos_executor.launched, driver).start()

    # Start executor and wait until it is stopped.
    driver_thread = ExecutorDriverThread(driver)
    driver_thread.start()
    try:
      while driver_thread.isAlive():
        driver_thread.join(5)
    except (KeyboardInterrupt, SystemExit):
      driver.stop()
      raise

    log.info('MesosExecutorDriver.run() has finished.')

  app.register_module(ExceptionTerminationHandler())
  app.main()
Example #7
0
def proxy_main():
  def main(args, options):
    plugins = list_plugins()

    if options.list_plugins:
      for plugin in plugins:
        print('\n%s' % plugin.__name__)
        if plugin.__doc__:
          for line in plugin.__doc__.splitlines():
            print('    %s' % line)
        else:
          print('    No information')
      return

    if options.plugins:
      plugins_map = dict((plugin.__name__, plugin) for plugin in plugins)
      plugins = list(filter(None, map(plugins_map.get, options.plugins)))

    if options.skip_plugins:
      plugins_map = dict((plugin.__name__, plugin) for plugin in plugins)
      for plugin in options.skip_plugins:
        plugins_map.pop(plugin, None)
      plugins = list(plugins_map.values())

    if not args and options.diff is None:
      options.diff = DEFAULT_BRANCH

    if options.diff:
      iterator = git_iterator(args, options)
    else:
      iterator = path_iterator(args, options)

    severity = Nit.COMMENT
    for number, name in Nit.SEVERITY.items():
      if name == options.severity:
        severity = number

    should_fail = False
    for filename, line_filter in iterator:
      try:
        python_file = PythonFile.parse(filename)
      except SyntaxError as e:
        print('%s:SyntaxError: %s' % (filename, e))
        continue
      for checker in plugins:
        for nit in apply_filter(python_file, checker, line_filter):
          if nit.severity >= severity:
            print(nit)
            print()
          should_fail |= nit.severity >= Nit.ERROR or (
              nit.severity >= Nit.WARNING and options.strict)

    return int(should_fail)

  app.main()
def proxy_main():
  def main(args, options):
    if MesosExecutorDriver is None:
      app.error('Could not load MesosExecutorDriver!')

    # status providers:
    status_providers = [
        HealthCheckerProvider(),
        ResourceManagerProvider(checkpoint_root=options.checkpoint_root)
    ]

    if options.announcer_enable:
      if options.announcer_ensemble is None:
        app.error('Must specify --announcer-ensemble if the announcer is enabled.')
      status_providers.append(DefaultAnnouncerCheckerProvider(
        options.announcer_ensemble, options.announcer_serverset_path))

    # Create executor stub
    if options.execute_as_user or options.nosetuid:
      # If nosetuid is set, execute_as_user is also None
      thermos_runner_provider = UserOverrideThermosTaskRunnerProvider(
        dump_runner_pex(),
        artifact_dir=os.path.abspath(CWD)
      )
      thermos_runner_provider.set_role(None)

      thermos_executor = AuroraExecutor(
        runner_provider=thermos_runner_provider,
        status_providers=status_providers,
        sandbox_provider=UserOverrideDirectorySandboxProvider(options.execute_as_user)
      )
    else:
      thermos_runner_provider = DefaultThermosTaskRunnerProvider(
        dump_runner_pex(),
        artifact_dir=os.path.abspath(CWD)
      )

      thermos_executor = AuroraExecutor(
        runner_provider=thermos_runner_provider,
        status_providers=status_providers
      )

    # Create driver stub
    driver = MesosExecutorDriver(thermos_executor)

    # This is an ephemeral executor -- shutdown if we receive no tasks within a certain
    # time period
    ExecutorTimeout(thermos_executor.launched, driver).start()

    # Start executor
    driver.run()

    log.info('MesosExecutorDriver.run() has finished.')

  app.main()
Example #9
0
def proxy_main():
  def main(args, options):
    log.info('Starting testing mysos executor')

    executor = MysosExecutor(
        FakeTaskRunnerProvider(FakeTaskControlProvider()), Sandbox(SANDBOX_ROOT))

    driver = mesos.native.MesosExecutorDriver(executor)
    driver.run()

    log.info('Exiting executor main')

  app.main()
def proxy_main():
  def main():
    if MesosExecutorDriver is None:
      app.error('Could not load MesosExecutorDriver!')

    thermos_gc_executor, metric_writer, driver = initialize()

    thermos_gc_executor.start()
    metric_writer.start()
    driver.run()

    log.info('MesosExecutorDriver.run() has finished.')

  app.main()
Example #11
0
def run():
  def main(_, opts):
    path_detector = FixedPathDetector(opts.root)
    task_observer = TaskObserver(path_detector)
    task_observer.start()
    server = configure_server(task_observer)

    thread = ExceptionalThread(target=lambda: server.run('0.0.0.0', opts.port, 'cherrypy'))
    thread.daemon = True
    thread.start()

    sleep_forever()

  app.main()
def proxy_main():
  def main():
    # Create executor stub
    thermos_gc_executor = ThermosGCExecutor(checkpoint_root=TaskPath.DEFAULT_CHECKPOINT_ROOT)
    thermos_gc_executor.start()

    # Start metrics collection
    metric_writer = DiskMetricWriter(thermos_gc_executor.metrics, ExecutorDetector.VARS_PATH)
    metric_writer.start()

    # Create driver stub
    driver = mesos.MesosExecutorDriver(thermos_gc_executor)

    # Start GC executor
    driver.run()

    log.info('MesosExecutorDriver.run() has finished.')

  app.main()
Example #13
0
def proxy_main():
  def main(args, options):
    if MesosExecutorDriver is None:
      app.error('Could not load MesosExecutorDriver!')

    thermos_executor = initialize(options)

    # Create driver stub
    driver = MesosExecutorDriver(thermos_executor)

    # This is an ephemeral executor -- shutdown if we receive no tasks within a certain
    # time period
    ExecutorTimeout(thermos_executor.launched, driver).start()

    # Start executor
    driver.run()

    log.info('MesosExecutorDriver.run() has finished.')

  app.main()
Example #14
0
def proxy_main():
  def main():
    if MesosExecutorDriver is None:
      app.error('Could not load MesosExecutorDriver!')

    # Create executor stub
    thermos_gc_executor = ThermosGCExecutor(FixedPathDetector(DEFAULT_CHECKPOINT_ROOT))
    thermos_gc_executor.start()

    # Start metrics collection
    metric_writer = DiskMetricWriter(thermos_gc_executor.metrics, ExecutorDetector.VARS_PATH)
    metric_writer.start()

    # Create driver stub
    driver = MesosExecutorDriver(thermos_gc_executor)

    # Start GC executor
    driver.run()

    log.info('MesosExecutorDriver.run() has finished.')

  app.main()
Example #15
0
def proxy_main():
  def main(args, options):
    # 'sandbox' directory resides under the working directory assigned by the Mesos slave.
    sandbox_root = os.path.join(os.path.realpath('.'), "sandbox")

    unpack_assets(sandbox_root, MYSOS_MODULE, ASSET_RELPATH, execute=chmod_scripts)

    log.info("Starting Vagrant Mysos executor within sandbox %s" % sandbox_root)

    sandbox = Sandbox(sandbox_root)
    executor = MysosExecutor(
        MysosTaskRunnerProvider(
            MySQLTaskControlProvider(),
            NoopPackageInstallerProvider(),  # Do not install any package.
            NoopBackupStoreProvider()),  # Do not recover any state.
        sandbox)
    driver = mesos.native.MesosExecutorDriver(executor)
    driver.run()

    log.info('Exiting executor main')

  app.main()
Example #16
0
def run():
    def main(args, opts):
        """Main"""
        zkconn = kazoo_client.TwitterKazooClient(opts.zk)
        zkconn.start()

        server = RedirServer(zkconn, opts.zk_basepath, opts.scheduler_url,
                             opts.subdomain, opts.base_domain)
        thread = ExceptionalThread(
            target=lambda: server.run(opts.listen,
                                      opts.port,
                                      server='cherrypy'))
        thread.daemon = True
        thread.start()

        # Wait forever, basically.
        thread.join()

    app.add_option('--port', help='http port', default=8080)
    app.add_option('--listen',
                   help='IP address to listen for http connections.',
                   default='0.0.0.0')
    app.add_option('--zk',
                   help='Zookeeper ensemble (comma-delimited)',
                   default='zookeeper:2181')
    app.add_option('--zk_basepath',
                   help='Zookeeper service path root.',
                   default='/aurora/svc')
    app.add_option('--scheduler_url',
                   help='Aurora scheduler URL')
    app.add_option('--base_domain',
                   help='Domain name of your site.')
    app.add_option('--subdomain',
                   help='Subdomain that roots Aurora job namespace.',
                   default='aurora')

    app.main()
Example #17
0
def proxy_main():
  app.main()
def proxy_main():
  main = runner_proxy_main

  app.main()
Example #19
0
def main(args):
  options = app.get_options()
  if options.show_help:
    app.help()

  if options.show_version or options.just_version:
    print >> sys.stdout, 'Python NailGun client version 0.0.1'
    if options.just_version:
      sys.exit(0)


  # Assume ng.pex has been aliased to the command name
  command = re.compile('.pex$').sub('', os.path.basename(sys.argv[0]))
  args_index = 0

  # Otherwise the command name is the 1st arg
  if command == 'ng':
    if not args:
      app.help()

    command = args[0]
    args_index = 1

  ng = NailgunClient(host=options.ng_host, port=options.ng_port)
  result = ng(command, *args[args_index:], **os.environ)
  sys.exit(result)


app.main()
Example #20
0
def proxy_main():
    main = runner_proxy_main  # noqa

    app.main()
Example #21
0
def proxy_main():
  app.add_option(
      '--port',
      dest='api_port',
      type='int',
      default=None,
      help='Port for the HTTP API server')

  app.add_option(
      '--mesos_master',
      dest='mesos_master',
      default=None,
      help='Mesos master address. It can be a ZooKeeper URL through which the master can be '
           'detected')

  app.add_option(
      '--framework_user',
      dest='framework_user',
      help='The Unix user that Mysos executor runs as')

  app.add_option(
      '--framework_role',
      dest='framework_role',
      default='*',
      help="The role that Mysos framework runs as. If set, Mysos only uses Mesos pool resources "
           "with that role. The default value '*' is what Mesos considers as the default role.\n"
           "NOTE: Mesos master needs to be configured to allow the specified role. See its --roles "
           "flag")

  app.add_option(
      '--executor_uri',
      dest='executor_uri',
      default=None,
      help='URI for the Mysos executor package')

  app.add_option(
      '--executor_cmd',
      dest='executor_cmd',
      default=None,
      help='Command to execute the executor package')

  app.add_option(
      '--executor_environ',
      dest='executor_environ',
      default=None,
      help="Environment variables for the executors (and the tasks) as a list of dicts keyed by "
           "{name, value} in JSON. Note that these variables don't affect Mesos slave components "
           "such as the fetcher")

  app.add_option(
      '--zk_url',
      dest='zk_url',
      default=None,
      help='ZooKeeper URL for various Mysos operations, in the form of '
           '"zk://*****:*****@servers/path". The sub-directory <zk_url>/discover is used for '
           'communicating MySQL cluster information between Mysos scheduler and executors')

  # TODO(jyx): This could also be made a per-cluster configuration.
  app.add_option(
      '--election_timeout',
      dest='election_timeout',
      default='60s',
      help='The amount of time the scheduler waits for all slaves to respond during a MySQL master '
           'election, e.g., 60s. After the timeout the master is elected from only the slaves that '
           'have responded')

  app.add_option(
      '--admin_keypath',
      dest='admin_keypath',
      default=None,
      help='The path to the key file with MySQL admin credentials on Mesos slaves')

  app.add_option(
      '--work_dir',
      dest='work_dir',
      default=os.path.join(tempfile.gettempdir(), 'mysos'),
      help="Directory path to place Mysos work directories, e.g., web assets, state files if "
           "--state_storage=local. Default to a system temp directory.")

  app.add_option(
      '--state_storage',
      dest='state_storage',
      default='zk',
      help="Mechanism to persist scheduler state. Available options are 'zk' and 'local'. If 'zk' "
           "is chosen, the scheduler state is stored under <zk_url>/state; see --zk_url. Otherwise "
           "'local' is chosen and the state is persisted under <work_dir>/state; see --work_dir")

  app.add_option(
      '--framework_failover_timeout',
      dest='framework_failover_timeout',
      default='14d',
      help='Time after which Mysos framework is considered deleted. This implies losing all tasks. '
           'SHOULD BE VERY HIGH')

  # TODO(jyx): Flags like this are generally optional but specific executor implementations may
  # require them. Consider adding validators that can be plugged in so configuration errors can be
  # caught in the scheduler.
  app.add_option(
      '--installer_args',
      dest='installer_args',
      default=None,
      help='Arguments for MySQL installer directly passed along to and parsed by the installer. '
           'e.g., a serialized JSON string'
  )

  app.add_option(
      '--backup_store_args',
      dest='backup_store_args',
      default=None,
      help="Arguments for the store for MySQL backups. Its use and format are defined by the "
           "backup store implementation. e.g., It can be a serialized JSON string"
  )

  app.add_option(
      '--framework_authentication_file',
      dest='framework_authentication_file',
      default=None,
      help="Path to the key file for authenticating the framework against Mesos master. Framework "
           "will fail to register with Mesos if authentication is required by Mesos and this "
           "option is not provided"
  )

  def main(args, options):
    log.info("Options in use: %s", options)

    if not options.api_port:
      app.error('Must specify --port')

    if not options.mesos_master:
      app.error('Must specify --mesos_master')

    if not options.framework_user:
      app.error('Must specify --framework_user')

    if not options.executor_uri:
      app.error('Must specify --executor_uri')

    if not options.executor_cmd:
      app.error('Must specify --executor_cmd')

    if not options.zk_url:
      app.error('Must specify --zk_url')

    if not options.admin_keypath:
      app.error('Must specify --admin_keypath')

    try:
      election_timeout = parse_time(options.election_timeout)
      framework_failover_timeout = parse_time(options.framework_failover_timeout)
    except InvalidTime as e:
      app.error(e.message)

    try:
      _, zk_servers, zk_root = zookeeper.parse(options.zk_url)
    except Exception as e:
      app.error("Invalid --zk_url: %s" % e.message)

    web_assets_dir = os.path.join(options.work_dir, "web")
    pkgutil.unpack_assets(web_assets_dir, MYSOS_MODULE, ASSET_RELPATH)
    log.info("Extracted web assets into %s" % options.work_dir)

    fw_principal = None
    fw_secret = None
    if options.framework_authentication_file:
      try:
        with open(options.framework_authentication_file, "r") as f:
          cred = yaml.load(f)
        fw_principal = cred["principal"]
        fw_secret = cred["secret"]
        log.info("Loaded credential (principal=%s) for framework authentication" % fw_principal)
      except IOError as e:
        app.error("Unable to read the framework authentication key file: %s" % e)
      except (KeyError, yaml.YAMLError) as e:
        app.error("Invalid framework authentication key file format %s" % e)

    log.info("Starting Mysos scheduler")

    kazoo = KazooClient(zk_servers)
    kazoo.start()

    if options.state_storage == 'zk':
      log.info("Using ZooKeeper (path: %s) for state storage" % zk_root)
      state_provider = ZooKeeperStateProvider(kazoo, zk_root)
    else:
      log.info("Using local disk for state storage")
      state_provider = LocalStateProvider(options.work_dir)

    try:
      state = state_provider.load_scheduler_state()
    except StateProvider.Error as e:
      app.error(e.message)

    if state:
      log.info("Successfully restored scheduler state")
      framework_info = state.framework_info
      if framework_info.HasField('id'):
        log.info("Recovered scheduler's FrameworkID is %s" % framework_info.id.value)
    else:
      log.info("No scheduler state to restore")
      framework_info = FrameworkInfo(
          user=options.framework_user,
          name=FRAMEWORK_NAME,
          checkpoint=True,
          failover_timeout=framework_failover_timeout.as_(Time.SECONDS),
          role=options.framework_role)
      if fw_principal:
        framework_info.principal = fw_principal
      state = Scheduler(framework_info)
      state_provider.dump_scheduler_state(state)

    scheduler = MysosScheduler(
        state,
        state_provider,
        options.framework_user,
        options.executor_uri,
        options.executor_cmd,
        kazoo,
        options.zk_url,
        election_timeout,
        options.admin_keypath,
        installer_args=options.installer_args,
        backup_store_args=options.backup_store_args,
        executor_environ=options.executor_environ,
        framework_role=options.framework_role)

    if fw_principal and fw_secret:
      cred = Credential(principal=fw_principal, secret=fw_secret)
      scheduler_driver = mesos.native.MesosSchedulerDriver(
          scheduler,
          framework_info,
          options.mesos_master,
          cred)
    else:
      scheduler_driver = mesos.native.MesosSchedulerDriver(
          scheduler,
          framework_info,
          options.mesos_master)

    scheduler_driver.start()

    server = HttpServer()
    server.mount_routes(MysosServer(scheduler, web_assets_dir))

    et = ExceptionalThread(
        target=server.run, args=('0.0.0.0', options.api_port, 'cherrypy'))
    et.daemon = True
    et.start()

    try:
      # Wait for the scheduler to stop.
      # The use of 'stopped' event instead of scheduler_driver.join() is necessary to stop the
      # process with SIGINT.
      while not scheduler.stopped.wait(timeout=0.5):
        pass
    except KeyboardInterrupt:
      log.info('Interrupted, exiting.')
    else:
      log.info('Scheduler exited.')

    app.shutdown(1)  # Mysos scheduler is supposed to be long-running thus the use of exit status 1.

  app.main()
Example #22
0
def proxy_main():
    app.main()
def proxy_main():
  main = runner_proxy_main  # noqa

  app.main()
Example #24
0
    if opts.sampling < 0 or opts.sampling > 1:
        sys.stdout.write("--sampling takes values within [0, 1]\n")
        sys.exit(1)

    stats = StatsServer(opts.iface,
                        opts.zookeeper_port,
                        opts.aggregation_depth,
                        opts.max_results,
                        opts.max_queued_requests,
                        opts.max_queued_replies,
                        opts.max_queued_events,
                        sampling=opts.sampling,
                        include_bytes=not opts.exclude_bytes)

    log.info("Starting with opts: %s" % (opts))

    signal.signal(signal.SIGINT, signal.SIG_DFL)

    server = Server()
    server.mount_routes(DiagnosticsEndpoints())
    server.mount_routes(stats)
    server.run(opts.http_addr, opts.http_port)

    stats.sniffer.join()


if __name__ == '__main__':
    setup()
    app.main()
Example #25
0
def proxy_main():
  @app.command
  @app.command_option(
      '--num_nodes',
      dest='num_nodes',
      type='int',
      help='Number of nodes this cluster should have')
  @app.command_option(
      '--backup_id',
      dest='backup_id',
      default=None,
      help="The 'backup_id' to restore from")
  @app.command_option(
      '--cluster_user',
      dest='cluster_user',
      help='MySQL user name the of cluster')
  def create(args, options):
    validate_common_options(options)

    if not options.num_nodes:
      app.error("--num_nodes is required")

    if not options.cluster_user:
      app.error("--cluster_user is required")

    url = 'http://%s:%s/clusters/%s' % (options.api_host, options.api_port, options.cluster_name)
    values = dict(
        num_nodes=int(options.num_nodes),
        cluster_user=options.cluster_user,
        backup_id=options.backup_id if options.backup_id else '')

    req = urllib2.Request(url, urllib.urlencode(values))
    try:
      response = urllib2.urlopen(req).read()
    except urllib2.HTTPError as e:
      log.error("POST request failed: %s, %s, %s" % (
          e.code, BaseHTTPServer.BaseHTTPRequestHandler.responses[e.code], e.read()))
      app.quit(1)

    try:
      result = json.loads(response)
      if not isinstance(result, dict):
        raise ValueError()
    except ValueError:
      log.error("Invalid response: %s" % response)
      app.quit(1)

    log.info("Cluster created. Cluster info: %s" % str(result))
    with open(options.password_file, 'w') as f:
      f.write(result["cluster_password"])

    log.info("Waiting for the master for this cluster to be elected...")
    master_endpoint = wait_for_master(result['cluster_url']).service_endpoint

    connection_str = "mysql://%s:%s@%s:%d/" % (
        options.cluster_user,
        result["cluster_password"],
        master_endpoint.host,
        master_endpoint.port)
    log.info("Connecting to the MySQL cluster master: %s" % connection_str)
    engine = create_engine(connection_str)

    for i in range(5):  # Loop for 5 times/seconds to wait for the master to be promoted.
      try:
        # TODO(jyx): Test writing to the master and reading from the slave.
        result = engine.execute("SELECT 1;").scalar()
        assert 1 == int(result), "Expecting result to be 1 but got %s" % result
        break
      except OperationalError:
        if i == 4:
          raise
        log.debug("MySQL master not ready yet. Sleep for 1 second...")
        time.sleep(1)

    log.info("Cluster successfully started")

  @app.command
  def delete(args, options):
    validate_common_options(options)

    with open(options.password_file, 'r') as f:
      password = f.read().strip()
      if not password:
        app.error("Empty password file")

    url = 'http://%s:%s/clusters/%s' % (options.api_host, options.api_port, options.cluster_name)
    values = dict(password=password)

    req = urllib2.Request(url, urllib.urlencode(values))
    req.get_method = lambda: 'DELETE'

    try:
      response = urllib2.urlopen(req).read()
    except urllib2.HTTPError as e:
      log.error("DELETE request failed: %s, %s, %s" % (
          e.code, BaseHTTPServer.BaseHTTPRequestHandler.responses[e.code], e.read()))
      app.quit(1)

    try:
      result = json.loads(response)
      if not isinstance(result, dict):
        raise ValueError()
    except ValueError:
      log.error("Invalid response: %s" % response)
      app.quit(1)

    log.info("Cluster deletion result: %s" % result)

    log.info("Waiting for the cluster to terminate...")
    wait_for_termination(result['cluster_url'])

    log.info("Cluster terminated/deleted")

  def validate_common_options(options):
    if not options.api_host:
      app.error("--api_host is required")

    if not options.api_port:
      app.error("--api_port is required")

    if not options.cluster_name:
      app.error("--cluster is required")

    if not options.password_file:
      app.error("--password_file is required")
    log.info("Using --password_file=%s" % options.password_file)
    safe_mkdir(os.path.dirname(options.password_file))

  def main(args, options):
    app.help()

  app.main()