~launchpad-pqm/launchpad/devel

# Copyright 2009 Canonical Ltd.  This software is licensed under the

# GNU Affero General Public License version 3 (see the file LICENSE).

"""Start and stop the Mailman processes."""

__metaclass__ = type

__all__ = [

    'start_mailman',

    'stop_mailman',

    ]

import errno

import os

import signal

import subprocess

import sys

import canonical

from lp.services.mailman.config import configure_prefix

from lp.services.mailman.monkeypatches import monkey_patch

def mailmanctl(command, quiet=False, config=None, *additional_arguments):

    """Run mailmanctl command.

    :param command: the command to use.

    :param quiet: when this is true, no output will happen unless, an error

        happens.

    :param config: The LaunchpadConfig object to take configuration from.

        Defaults to the global one.

    :param additional_arguments: additional command arguments to pass to the

        mailmanctl program.

    :raises RuntimeError: when quiet is True and the command failed.

    """

    if config is None:

        config = lp.services.config.config

    mailman_path = configure_prefix(config.mailman.build_prefix)

    mailman_bin = os.path.join(mailman_path, 'bin')

    args = ['./mailmanctl']

    args.extend(additional_arguments)

    args.append(command)

    if quiet:

        stdout = subprocess.PIPE

        stderr = subprocess.STDOUT

    else:

        stdout = None

        stderr = None

    env = dict(os.environ)

    env['LPCONFIG'] = config.instance_name

    process = subprocess.Popen(

        args, cwd=mailman_bin, stdout=stdout, stderr=stderr, env=env)

    code = process.wait()

    if code:

        if quiet:

            raise RuntimeError(

                'mailmanctl %s failed: %d\n%s' % (

                    command, code, process.stdout.read()))

        else:

            print >> sys.stderr, 'mailmanctl %s failed: %d' % (command, code)

def stop_mailman(quiet=False, config=None):

    """Alias for mailmanctl('stop')."""

    mailmanctl('stop', quiet, config)

    # Further, if the Mailman master pid file was not removed, then the

    # master watcher, and probably one of its queue runners, did not die.

    # Kill it hard and clean up after it.

    if config is None:

        config = lp.services.config.config

    mailman_path = configure_prefix(config.mailman.build_prefix)

    master_pid_path = os.path.join(mailman_path, 'data', 'master-qrunner.pid')

    try:

        master_pid_file = open(master_pid_path)

    except IOError, error:

        if error.errno == errno.ENOENT:

            # It doesn't exist, so we're all done.

            return

        raise

    try:

        master_pid = int(master_pid_file.read().strip())

    finally:

        master_pid_file.close()

    try:

        # Kill the entire process group.

        os.kill(master_pid, -signal.SIGKILL)

    except OSError, error:

        if error.errno == errno.ESRCH:

            # The process does not exist.  It could be a zombie that has yet

            # to be waited on, but let's not worry about that.

            return

        raise

    try:

        os.remove(master_pid_path)

    except OSError, error:

        if error.errno != errno.ENOENT:

            raise

    lock_dir = os.path.join(mailman_path, 'locks')

    for filename in os.listdir(lock_dir):

        os.remove(os.path.join(lock_dir, filename))

def start_mailman(quiet=False, config=None):

    """Start the Mailman master qrunner.

    The client of start_mailman() is responsible for ensuring that

    stop_mailman() is called at the appropriate time.

    :param quiet: when this is true, no output will happen unless, an error

        happens.

    :param config: The LaunchpadConfig object to take configuration from.

        Defaults to the global one.

    :raises RuntimeException: when Mailman fails to start successfully.

    """

    if config is None:

        config = lp.services.config.config

    # We need the Mailman bin directory so we can run some of Mailman's

    # command line scripts.

    mailman_path = configure_prefix(config.mailman.build_prefix)

    mailman_bin = os.path.join(mailman_path, 'bin')

    # Monkey-patch the installed Mailman 2.1 tree.

    monkey_patch(mailman_path, config)

    # Start Mailman.  Pass in the -s flag so that any stale master pid files

    # will get deleted.  "Stale" means the process that owned the pid no

    # longer exists, so this can't hurt anything.

    mailmanctl('start', quiet, config, '-s')