text: #  Copyright (c) 2015-2018 Cisco Systems, Inc.
  #
  #  Permission is hereby granted, free of charge, to any person obtaining a copy
  #  of this software and associated documentation files (the "Software"), to
  #  deal in the Software without restriction, including without limitation the
  #  rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
  #  sell copies of the Software, and to permit persons to whom the Software is
  #  furnished to do so, subject to the following conditions:
  #
  #  The above copyright notice and this permission notice shall be included in
  #  all copies or substantial portions of the Software.
  #
  #  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  #  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  #  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  #  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  #  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  #  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  #  DEALINGS IN THE SOFTWARE.
  
  import fcntl
  import os
  import signal
  import struct
  import sys
  import termios
  
  import click
  import pexpect
  
  from molecule import logger
  from molecule import scenarios
  from molecule import util
  from molecule.command import base
  
  LOG = logger.get_logger(__name__)
  
  
  class Login(base.Base):
      """
      .. program:: molecule login
  
      .. option:: molecule login
  
          Target the default scenario.
  
      .. program:: molecule login --scenario-name foo
  
      .. option:: molecule login --scenario-name foo
  
          Targeting a specific scenario.
  
      .. program:: molecule login --host hostname
  
      .. option:: molecule login --host hostname
  
          Targeting a specific running host.
  
      .. program:: molecule login --host hostname --scenario-name foo
  
      .. option:: molecule login --host hostname --scenario-name foo
  
          Targeting a specific running host and scenario.
  
      .. program:: molecule --debug login
  
      .. option:: molecule --debug login
  
          Executing with `debug`.
  
      .. program:: molecule --base-config base.yml login
  
      .. option:: molecule --base-config base.yml login
  
          Executing with a `base-config`.
  
      .. program:: molecule --env-file foo.yml login
  
      .. option:: molecule --env-file foo.yml login
  
          Load an env file to read variables from when rendering
          molecule.yml.
      """
  
      def __init__(self, c):
          super(Login, self).__init__(c)
          self._pt = None
  
      def execute(self):
          """
          Execute the actions necessary to perform a `molecule login` and
          returns None.
  
          :return: None
          """
          c = self._config
          if (not c.state.created) and c.driver.managed:
              msg = 'Instances not created.  Please create instances first.'
              util.sysexit_with_message(msg)
  
          hosts = [d['name'] for d in self._config.platforms.instances]
          hostname = self._get_hostname(hosts)
          self._get_login(hostname)
  
      def _get_hostname(self, hosts):
          hostname = self._config.command_args.get('host')
          if hostname is None:
              if len(hosts) == 1:
                  hostname = hosts[0]
              else:
                  msg = (
                      'There are {} running hosts. Please specify '
                      'which with --host.\n\n'
                      'Available hosts:\n{}'.format(len(hosts), '\n'.join(sorted(hosts)))
                  )
                  util.sysexit_with_message(msg)
          match = [x for x in hosts if x.startswith(hostname)]
          if len(match) == 0:
              msg = (
                  "There are no hosts that match '{}'.  You "
                  'can only login to valid hosts.'
              ).format(hostname)
              util.sysexit_with_message(msg)
          elif len(match) != 1:
              # If there are multiple matches, but one of them is an exact string
              # match, assume this is the one they're looking for and use it.
              if hostname in match:
                  match = [hostname]
              else:
                  msg = (
                      "There are {} hosts that match '{}'. You "
                      'can only login to one at a time.\n\n'
                      'Available hosts:\n{}'.format(
                          len(match), hostname, '\n'.join(sorted(hosts))
                      )
                  )
                  util.sysexit_with_message(msg)
  
          return match[0]
  
      def _get_login(self, hostname):  # pragma: no cover
          lines, columns = os.popen('stty size', 'r').read().split()
          login_options = self._config.driver.login_options(hostname)
          login_options['columns'] = columns
          login_options['lines'] = lines
          login_cmd = self._config.driver.login_cmd_template.format(**login_options)
  
          dimensions = (int(lines), int(columns))
          cmd = '/usr/bin/env {}'.format(login_cmd)
          self._pt = pexpect.spawn(cmd, dimensions=dimensions)
          signal.signal(signal.SIGWINCH, self._sigwinch_passthrough)
          self._pt.interact()
  
      def _sigwinch_passthrough(self, sig, data):  # pragma: no cover
          tiocgwinsz = 1074295912  # assume
          if 'TIOCGWINSZ' in dir(termios):
              tiocgwinsz = termios.TIOCGWINSZ
          s = struct.pack('HHHH', 0, 0, 0, 0)
          a = struct.unpack('HHHH', fcntl.ioctl(sys.stdout.fileno(), tiocgwinsz, s))
          self._pt.setwinsize(a[0], a[1])
  
  
  @click.command()
  @click.pass_context
  @click.option('--host', '-h', help='Host to access.')
  @click.option(
      '--scenario-name',
      '-s',
      default=base.MOLECULE_DEFAULT_SCENARIO_NAME,
      help='Name of the scenario to target. ({})'.format(
          base.MOLECULE_DEFAULT_SCENARIO_NAME
      ),
  )
  def login(ctx, host, scenario_name):  # pragma: no cover
      """ Log in to one instance. """
      args = ctx.obj.get('args')
      subcommand = base._get_subcommand(__name__)
      command_args = {'subcommand': subcommand, 'host': host}
  
      s = scenarios.Scenarios(base.get_configs(args, command_args), scenario_name)
      for scenario in s.all:
          base.execute_subcommand(scenario.config, subcommand)
  