src/mailman/commands/cli_control.py

   1 # Copyright (C) 2009 by the Free Software Foundation, Inc.
   2 #
   3 # This file is part of GNU Mailman.
   4 #
   5 # GNU Mailman is free software: you can redistribute it and/or modify it under
   6 # the terms of the GNU General Public License as published by the Free
   7 # Software Foundation, either version 3 of the License, or (at your option)
   8 # any later version.
   9 #
  10 # GNU Mailman is distributed in the hope that it will be useful, but WITHOUT
  11 # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12 # FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13 # more details.
  14 #
  15 # You should have received a copy of the GNU General Public License along with
  16 # GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
  17
  18 """Module stuff."""
  19
  20 from __future__ import absolute_import, unicode_literals
  21
  22 __metaclass__ = type
  23 __all__ = [
  24     'Reopen',
  25     'Restart',
  26     'Start',
  27     'Stop',
  28     ]
  29
  30
  31 import os
  32 import sys
  33 import signal
  34 import logging
  35
  36 from zope.interface import implements
  37
  38 from mailman.config import config
  39 from mailman.i18n import _
  40 from mailman.interfaces.command import ICLISubCommand
  41
  42
  43 qlog = logging.getLogger('mailman.qrunner')
  44
  45
  46 \f
  47 class Start:
  48     """Start the Mailman daemons."""
  49
  50     implements(ICLISubCommand)
  51
  52     name = 'start'
  53
  54     def add(self, parser, command_parser):
  55         """See `ICLISubCommand`."""
  56         command_parser.add_argument(
  57             '-f', '--force',
  58             default=False, action='store_true',
  59             help=_("""\
  60             If the master watcher finds an existing master lock, it will
  61             normally exit with an error message.  With this option,the master
  62             will perform an extra level of checking.  If a process matching
  63             the host/pid described in the lock file is running, the master
  64             will still exit, requiring you to manually clean up the lock.  But
  65             if no matching process is found, the master will remove the
  66             apparently stale lock and make another attempt to claim the master
  67             lock."""))
  68         command_parser.add_argument(
  69             '-u', '--run-as-user',
  70             default=True, action='store_false',
  71             help=_("""\
  72             Normally, this script will refuse to run if the user id and group
  73             id are not set to the 'mailman' user and group (as defined when
  74             you configured Mailman).  If run as root, this script will change
  75             to this user and group before the check is made.
  76
  77             This can be inconvenient for testing and debugging purposes, so
  78             the -u flag means that the step that sets and checks the uid/gid
  79             is skipped, and the program is run as the current user and group.
  80             This flag is not recommended for normal production environments.
  81
  82             Note though, that if you run with -u and are not in the mailman
  83             group, you may have permission problems, such as begin unable to
  84             delete a list's archives through the web.  Tough luck!"""))
  85         command_parser.add_argument(
  86             '-q', '--quiet',
  87             default=False, action='store_true',
  88             help=_("""\
  89             Don't print status messages.  Error messages are still printed to
  90             standard error."""))
  91
  92     def process(self, args):
  93         """See `ICLISubCommand`."""
  94         def log(message):
  95             if not args.quiet:
  96                 print message
  97         # Daemon process startup according to Stevens, Advanced Programming in
  98         # the UNIX Environment, Chapter 13.
  99         pid = os.fork()
 100         if pid:
 101             # parent
 102             log(_("Starting Mailman's master qrunner"))
 103             return
 104         # child: Create a new session and become the session leader, but since
 105         # we won't be opening any terminal devices, don't do the
 106         # ultra-paranoid suggestion of doing a second fork after the setsid()
 107         # call.
 108         os.setsid()
 109         # Instead of cd'ing to root, cd to the Mailman runtime directory.
 110         os.chdir(config.VAR_DIR)
 111         # Exec the master watcher.
 112         execl_args = [
 113             sys.executable, sys.executable,
 114             os.path.join(config.BIN_DIR, 'master'),
 115             ]
 116         if args.force:
 117             execl_args.append('--force')
 118         if args.config:
 119             execl_args.extend(['-C', args.config])
 120         qlog.debug('starting: %s', execl_args)
 121         os.execl(*execl_args)
 122         # We should never get here.
 123         raise RuntimeError('os.execl() failed')
 124
 125
 126 \f
 127 def kill_watcher(sig):
 128     try:
 129         with open(config.PIDFILE) as fp:
 130             pid = int(fp.read().strip())
 131     except (IOError, ValueError) as error:
 132         # For i18n convenience
 133         print >> sys.stderr, _('PID unreadable in: $config.PIDFILE')
 134         print >> sys.stderr, error
 135         print >> sys.stderr, _('Is qrunner even running?')
 136         return
 137     try:
 138         os.kill(pid, sig)
 139     except OSError as error:
 140         if e.errno != errno.ESRCH:
 141             raise
 142         print >> sys.stderr, _('No child with pid: $pid')
 143         print >> sys.stderr, e
 144         print >> sys.stderr, _('Stale pid file removed.')
 145         os.unlink(config.PIDFILE)
 146
 147
 148 \f
 149 class SignalCommand:
 150     """Common base class for simple, signal sending commands."""
 151
 152     implements(ICLISubCommand)
 153
 154     name = None
 155     message = None
 156     signal = None
 157
 158     def add(self, parser, command_parser):
 159         """See `ICLISubCommand`."""
 160         command_parser.add_argument(
 161             '-q', '--quiet',
 162             default=False, action='store_true',
 163             help=_("""\
 164             Don't print status messages.  Error messages are still printed to
 165             standard error."""))
 166
 167     def process(self, args):
 168         """See `ICLISubCommand`."""
 169         if not args.quiet:
 170             print _(self.message)
 171         kill_watcher(self.signal)
 172
 173
 174 class Stop(SignalCommand):
 175     """Stop the Malman daemons."""
 176
 177     name = 'stop'
 178     message = _("Shutting down Mailman's master qrunner")
 179     signal = signal.SIGTERM
 180
 181
 182 class Reopen(SignalCommand):
 183     """Reopen the Mailman daemons."""
 184
 185     name = 'reopen'
 186     message = _('Reopening the Mailman qrunners')
 187     signal = signal.SIGHUP
 188
 189
 190 class Restart(SignalCommand):
 191     """Stop the Mailman daemons."""
 192
 193     implements(ICLISubCommand)
 194
 195     name = 'restart'
 196     message = _('Restarting the Mailman qrunners')
 197     signal = signal.SIGUSR1