src/mailman/mta/postfix.py

   1 # Copyright (C) 2001-2016 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 """Creation/deletion hooks for the Postfix MTA."""
  19
  20 import os
  21 import logging
  22
  23 from flufl.lock import Lock
  24 from mailman import public
  25 from mailman.config import config
  26 from mailman.config.config import external_configuration
  27 from mailman.interfaces.listmanager import IListManager
  28 from mailman.interfaces.mta import (
  29     IMailTransportAgentAliases, IMailTransportAgentLifecycle)
  30 from mailman.utilities.datetime import now
  31 from operator import attrgetter
  32 from zope.component import getUtility
  33 from zope.interface import implementer
  34
  35
  36 log = logging.getLogger('mailman.error')
  37 ALIASTMPL = '{0:{2}}lmtp:[{1.mta.lmtp_host}]:{1.mta.lmtp_port}'
  38 NL = '\n'
  39
  40
  41 class _FakeList:
  42     """Duck-typed list for the `IMailTransportAgentAliases` interface."""
  43
  44     def __init__(self, list_name, mail_host):
  45         self.list_name = list_name
  46         self.mail_host = mail_host
  47         self.posting_address = '{}@{}'.format(list_name, mail_host)
  48
  49
  50 @public
  51 @implementer(IMailTransportAgentLifecycle)
  52 class LMTP:
  53     """Connect Mailman to Postfix via LMTP."""
  54
  55     def __init__(self):
  56         # Locate and read the Postfix specific configuration file.
  57         mta_config = external_configuration(config.mta.configuration)
  58         self.postmap_command = mta_config.get('postfix', 'postmap_command')
  59
  60     def create(self, mlist):
  61         """See `IMailTransportAgentLifecycle`."""
  62         # We can ignore the mlist argument because for LMTP delivery, we just
  63         # generate the entire file every time.
  64         self.regenerate()
  65
  66     delete = create
  67
  68     def regenerate(self, directory=None):
  69         """See `IMailTransportAgentLifecycle`."""
  70         # Acquire a lock file to prevent other processes from racing us here.
  71         if directory is None:
  72             directory = config.DATA_DIR
  73         lock_file = os.path.join(config.LOCK_DIR, 'mta')
  74         with Lock(lock_file):
  75             lmtp_path = os.path.join(directory, 'postfix_lmtp')
  76             lmtp_path_new = lmtp_path + '.new'
  77             with open(lmtp_path_new, 'w') as fp:
  78                 self._generate_lmtp_file(fp)
  79             # Atomically rename to the intended path.
  80             os.rename(lmtp_path_new, lmtp_path)
  81             domains_path = os.path.join(directory, 'postfix_domains')
  82             domains_path_new = domains_path + '.new'
  83             with open(domains_path_new, 'w') as fp:
  84                 self._generate_domains_file(fp)
  85             # Atomically rename to the intended path.
  86             os.rename(domains_path_new, domains_path)
  87             # Now, run the postmap command on both newly generated files.  If
  88             # one files, still try the other one.
  89             errors = []
  90             for path in (lmtp_path, domains_path):
  91                 command = self.postmap_command + ' ' + path
  92                 status = (os.system(command) >> 8) & 0xff
  93                 if status:
  94                     msg = 'command failure: %s, %s, %s'
  95                     errstr = os.strerror(status)
  96                     log.error(msg, command, status, errstr)
  97                     errors.append(msg % (command, status, errstr))
  98             if errors:
  99                 raise RuntimeError(NL.join(errors))
 100
 101     def _generate_lmtp_file(self, fp):
 102         # The format for Postfix's LMTP transport map is defined here:
 103         # http://www.postfix.org/transport.5.html
 104         #
 105         # Sort all existing mailing list names first by domain, then by
 106         # local part.  For Postfix we need a dummy entry for the domain.
 107         list_manager = getUtility(IListManager)
 108         utility = getUtility(IMailTransportAgentAliases)
 109         by_domain = {}
 110         sort_key = attrgetter('list_name')
 111         for list_name, mail_host in list_manager.name_components:
 112             mlist = _FakeList(list_name, mail_host)
 113             by_domain.setdefault(mlist.mail_host, []).append(mlist)
 114         print("""\
 115 # AUTOMATICALLY GENERATED BY MAILMAN ON {0}
 116 #
 117 # This file is generated by Mailman, and is kept in sync with the binary hash
 118 # file.  YOU SHOULD NOT MANUALLY EDIT THIS FILE unless you know what you're
 119 # doing, and can keep the two files properly in sync.  If you screw it up,
 120 # you're on your own.
 121     """.format(now().replace(microsecond=0)), file=fp)
 122         for domain in sorted(by_domain):
 123             print("""\
 124 # Aliases which are visible only in the @{0} domain.""".format(domain),
 125                   file=fp)
 126             for mlist in sorted(by_domain[domain], key=sort_key):
 127                 aliases = list(utility.aliases(mlist))
 128                 width = max(len(alias) for alias in aliases) + 3
 129                 print(ALIASTMPL.format(aliases.pop(0), config, width), file=fp)
 130                 for alias in aliases:
 131                     print(ALIASTMPL.format(alias, config, width), file=fp)
 132                 print(file=fp)
 133
 134     def _generate_domains_file(self, fp):
 135         # Uniquify the domains, then sort them alphabetically.
 136         domains = set()
 137         for list_name, mail_host in getUtility(IListManager).name_components:
 138             domains.add(mail_host)
 139         print("""\
 140 # AUTOMATICALLY GENERATED BY MAILMAN ON {0}
 141 #
 142 # This file is generated by Mailman, and is kept in sync with the binary hash
 143 # file.  YOU SHOULD NOT MANUALLY EDIT THIS FILE unless you know what you're
 144 # doing, and can keep the two files properly in sync.  If you screw it up,
 145 # you're on your own.
 146 """.format(now().replace(microsecond=0)), file=fp)
 147         for domain in sorted(domains):
 148             print('{0} {0}'.format(domain), file=fp)
 149         print(file=fp)