VirtualMailManager/transport.py
author martin f. krafft <madduck@madduck.net>
Tue, 10 Apr 2012 22:56:30 +0200
branchv0.6.x
changeset 514 d863a44a6353
parent 449 6826acb9b0a7
child 568 14abdd04ddf5
permissions -rw-r--r--
Make PL/pgSQL function feed back identity for mailboxes/relocated when there are catchall destinations. Without catchall aliases, if no virtual_alias matches, the query can just return NULL and Postfix will later check mailboxes/relocated for the address to rewrite. However, since virtual aliases are handled long before mailboxes/relocated, a catchall alias would also catch mail to mailboxes and relocated addresses, which we do not want. The way to tell postfix to keep delivering is for the virtual alias map to return the search key itself (identity function). This patch changes the postfix_virtual_alias_maps Pl/pgSQL function to do exactly that, but only if there are catchall destinations defined for the domain in question — otherwise it returns NULL when no match is found.

# -*- coding: UTF-8 -*-
# Copyright (c) 2008 - 2011, Pascal Volk
# See COPYING for distribution information.
"""
    VirtualMailManager.transport
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    Virtual Mail Manager's Transport class to manage the transport for
    domains and accounts.
"""

from VirtualMailManager.pycompat import any

_ = lambda msg: msg


class Transport(object):
    """A wrapper class that provides access to the transport table"""
    __slots__ = ('_tid', '_transport', '_dbh')

    def __init__(self, dbh, tid=None, transport=None):
        """Creates a new Transport instance.

        Either tid or transport must be specified. When both arguments
        are given, tid will be used.

        Keyword arguments:
        dbh -- a pyPgSQL.PgSQL.connection
        tid -- the id of a transport (int/long)
        transport -- the value of the transport (str)

        """
        self._dbh = dbh
        self._tid = 0
        assert any((tid, transport))
        if tid:
            assert not isinstance(tid, bool) and isinstance(tid, (int, long))
            self._load_by_id(tid)
        else:
            assert isinstance(transport, basestring)
            self._transport = transport
            self._load_by_name()

    @property
    def tid(self):
        """The transport's unique ID."""
        return self._tid

    @property
    def transport(self):
        """The transport's value, ex: 'dovecot:'"""
        return self._transport

    def __eq__(self, other):
        if isinstance(other, self.__class__):
            return self._tid == other._tid
        return NotImplemented

    def __ne__(self, other):
        if isinstance(other, self.__class__):
            return self._tid != other._tid
        return NotImplemented

    def __str__(self):
        return self._transport

    def _load_by_id(self, tid):
        """load a transport by its id from the database"""
        dbc = self._dbh.cursor()
        dbc.execute('SELECT transport FROM transport WHERE tid = %s', (tid,))
        result = dbc.fetchone()
        dbc.close()
        if not result:
            raise ValueError('Unknown transport id specified: %r' % tid)
        self._transport = result[0]
        self._tid = tid

    def _load_by_name(self):
        """Load a transport by its transport name from the database."""
        dbc = self._dbh.cursor()
        dbc.execute('SELECT tid FROM transport WHERE transport = %s',
                    (self._transport,))
        result = dbc.fetchone()
        dbc.close()
        if result:
            self._tid = result[0]
        else:
            self._save()

    def _save(self):
        """Save the new transport in the database."""
        dbc = self._dbh.cursor()
        dbc.execute("SELECT nextval('transport_id')")
        self._tid = dbc.fetchone()[0]
        dbc.execute('INSERT INTO transport (tid, transport) VALUES (%s, %s)',
                    (self._tid, self._transport))
        self._dbh.commit()
        dbc.close()

del _