py/toolkit/installer.py

#!/usr/bin/python -Bu
#
# Copyright (c) 2014 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""Factory toolkit installer.

The factory toolkit is a self-extracting shellball containing factory test
related files and this installer. This installer is invoked when the toolkit
is deployed and is responsible for installing files.
"""


import argparse
from contextlib import contextmanager
import os
import re
import sys
import tempfile

import factory_common  # pylint: disable=W0611
from cros.factory.test import factory
from cros.factory.tools.mount_partition import MountPartition
from cros.factory.utils.process_utils import Spawn


INSTALLER_PATH = 'usr/local/factory/py/toolkit/installer.py'

# Short and sweet help header for the executable generated by makeself.
HELP_HEADER = """
Installs the factory toolkit, transforming a test image into a factory test
image. You can:

- Install the factory toolkit on a CrOS device that is running a test
  image.  To do this, copy install_factory_toolkit.run to the device and
  run it.  The factory tests will then come up on the next boot.

    rsync -a install_factory_toolkit.run crosdevice:/tmp
    ssh crosdevice '/tmp/install_factory_toolkit.run && sync && reboot'

- Modify a test image, turning it into a factory test image.  When you
  use the image on a device, the factory tests will come up.

    install_factory_toolkit.run chromiumos_test_image.bin
"""

HELP_HEADER_ADVANCED = """
- (advanced) Modify a mounted stateful partition, turning it into a factory
  test image.  This is equivalent to the previous command:

    mount_partition -rw chromiumos_test_image.bin 1 /mnt/stateful
    install_factory_toolkit.run /mnt/stateful
    umount /mnt/stateful

- (advanced) Unpack the factory toolkit, modify a file, and then repack it.

    # Unpack but don't actually install
    install_factory_toolkit.run --target /tmp/toolkit --noexec
    # Edit some files in /tmp/toolkit
    emacs /tmp/toolkit/whatever
    # Repack
    install_factory_toolkit.run -- --repack /tmp/toolkit \\
        --pack-into /path/to/new/install_factory_toolkit.run
"""

# The makeself-generated header comes next.  This is a little confusing,
# so explain.
HELP_HEADER_MAKESELF = """
For complete usage information and advanced operations, run
"install_factory_toolkit.run -- --help" (note the extra "--").

Following is the help message from makeself, which was used to create
this self-extracting archive.

-----
"""


class FactoryToolkitInstaller():
  """Factory toolkit installer.

  Args:
    src: Source path containing usr/ and var/.
    dest: Installation destination path. Set this to the mount point of the
          stateful partition if patching a test image.
    no_enable: True to not install the tag file.
    system_root: The path to the root of the file system. This must be left
                 as its default value except for unit testing.
  """

  def __init__(self, src, dest, no_enable, system_root='/'):
    self._src = src
    self._system_root = system_root
    if dest == self._system_root:
      self._usr_local_dest = os.path.join(dest, 'usr', 'local')
      self._var_dest = os.path.join(dest, 'var')

      # Make sure we're on a CrOS device.
      lsb_release = self._ReadLSBRelease()
      is_cros = (
        lsb_release and
        re.match('^CHROMEOS_RELEASE', lsb_release, re.MULTILINE) is not None)

      if not is_cros:
        sys.stderr.write(
            "ERROR: You're not on a CrOS device (/etc/lsb-release does not\n"
            "contain CHROMEOS_RELEASE), so you must specify a test image or a\n"
            "mounted stateful partition on which to install the factory\n"
            "toolkit.  Please run\n"
            "\n"
            "  install_factory_toolkit.run -- --help\n"
            "\n"
            "for help.\n")
        sys.exit(1)
      if os.getuid() != 0:
        raise Exception('You must be root to install the factory toolkit on a '
                        'CrOS device.')
    else:
      self._usr_local_dest = os.path.join(dest, 'dev_image')
      self._var_dest = os.path.join(dest, 'var_overlay')
      if (not os.path.exists(self._usr_local_dest) or
          not os.path.exists(self._var_dest)):
        raise Exception(
            'The destination path %s is not a stateful partition!' % dest)

    self._dest = dest
    self._usr_local_src = os.path.join(src, 'usr', 'local')
    self._var_src = os.path.join(src, 'var')
    self._no_enable = no_enable
    self._tag_file = os.path.join(self._usr_local_dest, 'factory', 'enabled')

    if (not os.path.exists(self._usr_local_src) or
        not os.path.exists(self._var_src)):
      raise Exception(
          'This installer must be run from within the factory toolkit!')

  @staticmethod
  def _ReadLSBRelease():
    """Returns the contents of /etc/lsb-release, or None if it does not
    exist."""
    if os.path.exists('/etc/lsb-release'):
      with open('/etc/lsb-release') as f:
        return f.read()
    return None

  def WarningMessage(self, target_test_image=None):
    with open(os.path.join(self._src, 'VERSION')) as f:
      ret = f.read()
    if target_test_image:
      ret += (
          '\n'
          '\n'
          '*** You are about to patch the factory toolkit into:\n'
          '***   %s\n'
          '***' % target_test_image)
    else:
      ret += (
          '\n'
          '\n'
          '*** You are about to install the factory toolkit to:\n'
          '***   %s\n'
          '***' % self._dest)
    if self._dest == self._system_root:
      if self._no_enable:
        ret += ('\n'
          '*** Factory tests will be disabled after this process is done, but\n'
          '*** you can enable them by creating the factory enabled tag:\n'
          '***   %s\n'
          '***' % self._tag_file)
      else:
        ret += ('\n'
          '*** After this process is done, your device will start factory\n'
          '*** tests on the next reboot.\n'
          '***\n'
          '*** Factory tests can be disabled by deleting the factory enabled\n'
          '*** tag:\n'
          '***   %s\n'
          '***' % self._tag_file)
    return ret

  def _Rsync(self, src, dest):
    print '***   %s -> %s' % (src, dest)
    Spawn(['rsync', '-a', src + '/', dest],
          sudo=True, log=True, check_output=True)

  def Install(self):
    print '*** Installing factory toolkit...'
    self._Rsync(self._usr_local_src, self._usr_local_dest)
    self._Rsync(self._var_src, self._var_dest)

    if self._no_enable:
      print '*** Removing factory enabled tag...'
      try:
        os.unlink(self._tag_file)
      except OSError:
        pass
    else:
      print '*** Installing factory enabled tag...'
      open(self._tag_file, 'w').close()

    print '*** Installation completed.'


@contextmanager
def DummyContext(arg):
  """A context manager that simply yields its argument."""
  yield arg


def PrintBuildInfo(src_root):
  """Print build information."""
  info_file = os.path.join(src_root, 'REPO_STATUS')
  if not os.path.exists(info_file):
    raise OSError('Build info file not found!')
  with open(info_file, 'r') as f:
    print f.read()


def PackFactoryToolkit(src_root, output_path):
  """Packs the files containing this script into a factory toolkit."""
  with open(os.path.join(src_root, 'VERSION'), 'r') as f:
    version = f.read().strip()
  with tempfile.NamedTemporaryFile() as help_header:
    help_header.write(version + "\n" + HELP_HEADER + HELP_HEADER_MAKESELF)
    help_header.flush()
    Spawn([os.path.join(src_root, 'makeself.sh'), '--bzip2', '--nox11',
           '--help-header', help_header.name,
           src_root, output_path, version, INSTALLER_PATH, '--in-exe'],
          check_call=True, log=True)
  print ('\n'
      '  Factory toolkit generated at %s.\n'
      '\n'
      '  To install factory toolkit on a live device running a test image,\n'
      '  copy this to the device and execute it as root.\n'
      '\n'
      '  Alternatively, the factory toolkit can be used to patch a test\n'
      '  image. For more information, run:\n'
      '    %s --help\n'
      '\n' % (output_path, output_path))


def main():
  import logging
  logging.basicConfig(level=logging.INFO)

  # In order to determine which usage message to show, first determine
  # whether we're in the self-extracting archive.  Do this first
  # because we need it to even parse the arguments.
  if '--in-exe' in sys.argv:
    sys.argv = [x for x in sys.argv if x != '--in-exe']
    in_archive = True
  else:
    in_archive = False

  parser = argparse.ArgumentParser(
      description=HELP_HEADER + HELP_HEADER_ADVANCED,
      usage=('install_factory_toolkit.run -- [options]' if in_archive
             else None),
      formatter_class=argparse.RawDescriptionHelpFormatter)
  parser.add_argument('dest', nargs='?', default='/',
      help='A test image or the mount point of the stateful partition. '
           "If omitted, install to live system, i.e. '/'.")
  parser.add_argument('--no-enable', '-n', action='store_true',
      help="Don't enable factory tests after installing")
  parser.add_argument('--yes', '-y', action='store_true',
      help="Don't ask for confirmation")
  parser.add_argument('--build-info', action='store_true',
      help="Print build information and exit")
  parser.add_argument('--pack-into', metavar='NEW_TOOLKIT',
      help="Pack the files into a new factory toolkit")
  parser.add_argument('--repack', metavar='UNPACKED_TOOLKIT',
      help="Repack from previously unpacked toolkit")
  args = parser.parse_args()

  src_root = factory.FACTORY_PATH
  for _ in xrange(3):
    src_root = os.path.dirname(src_root)

  # --pack-into may be called directly so this must be done before changing
  # working directory to OLDPWD.
  if args.pack_into and args.repack is None:
    PackFactoryToolkit(src_root, args.pack_into)
    return

  if not in_archive:
    # If you're not in the self-extracting archive, you're not allowed to
    # do anything except the above --pack-into call.
    parser.error('Not running from install_factory_toolkit.run; '
                 'only --pack-into (without --repack) is allowed')

  # Change to original working directory in case the user specifies
  # a relative path.
  # TODO: Use USER_PWD instead when makeself is upgraded
  os.chdir(os.environ['OLDPWD'])

  if args.repack:
    if args.pack_into is None:
      parser.error('Must specify --pack-into when using --repack.')
    Spawn([os.path.join(args.repack, INSTALLER_PATH),
           '--pack-into', args.pack_into], check_call=True, log=True)
    return

  if args.build_info:
    PrintBuildInfo(src_root)
    return

  if not os.path.exists(args.dest):
    parser.error('Destination %s does not exist!' % args.dest)

  patch_test_image = os.path.isfile(args.dest)

  with (MountPartition(args.dest, 1, rw=True) if patch_test_image
        else DummyContext(args.dest)) as dest:
    installer = FactoryToolkitInstaller(src_root, dest, args.no_enable)

    print installer.WarningMessage(args.dest if patch_test_image else None)

    if not args.yes:
      answer = raw_input('*** Continue? [y/N] ')
      if not answer or answer[0] not in 'yY':
        sys.exit('Aborting.')

    installer.Install()

if __name__ == '__main__':
  main()