doc/source/vmm_alias.rst
author martin f. krafft <madduck@madduck.net>
Tue, 10 Apr 2012 22:56:30 +0200
branchv0.6.x
changeset 514 d863a44a6353
parent 220 8b8d632f0ef3
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.

:mod:`VirtualMailManager.Alias` --- Handling of alias e-mail addresses
======================================================================

.. module:: VirtualMailManager.Alias
  :synopsis: Handling of alias e-mail addresses

.. moduleauthor:: Pascal Volk <neverseen@users.sourceforge.net>

.. toctree::
   :maxdepth: 2


This module provides the :class:`Alias` class. The data are read from/stored
in the ``alias`` table. This table is used by Postfix to rewrite recipient
addresses.


Alias
---------
.. class:: Alias(dbh, address)
  
  Creates a new *Alias* instance. Alias instances provides the :func:`__len__`
  method. So the existence of an alias in the database can be tested with a
  simple if condition.
  
  :param dbh: a database connection
  :type dbh: :class:`pyPgSQL.PgSQL.Connection`
  :param address: the alias e-mail address.
  :type address: :class:`VirtualMailManager.EmailAddress.EmailAddress`

  .. method:: add_destinations(destinations, expansion_limit [, warnings=None])

    Adds the *destinations* to the destinations of the alias. This method
    returns a ``set`` of all addresses which successfully were stored into the
    database.

    If one of the e-mail addresses in *destinations* is the same as the alias
    address, it will be silently discarded. Destination addresses, that are
    already assigned to the alias, will be also ignored.

    When the optional *warnings* list is given, all ignored addresses will be
    appended to it.

    :param destinations: The destination addresses of the alias
    :type destinations: :obj:`list` of
      :class:`VirtualMailManager.EmailAddress.EmailAddress` instances
    :param expansion_limit: The maximal number of destinations (see also:
      `virtual_alias_expansion_limit
      <http://www.postfix.org/postconf.5.html#virtual_alias_expansion_limit>`_)
    :type expansion_limit: :obj:`int`
    :param warnings: A optional list, to record all ignored addresses
    :type warnings: :obj:`list`
    :rtype: :obj:`set`
    :raise VirtualMailManager.errors.AliasError: if the additional
      *destinations* will exceed the *expansion_limit* or if the alias
      already exceeds its *expansion_limit*.

    .. seealso:: :mod:`VirtualMailManager.ext.postconf` -- to read actual
      values of Postfix configuration parameters.


  .. method:: del_destination(destination)

    Deletes the given *destination* address from the alias.

    :param destination: a destination address of the alias
    :type destination: :class:`VirtualMailManager.EmailAddress.EmailAddress`
    :rtype: :obj:`None`
    :raise VirtualMailManager.errors.AliasError: if the destination wasn't
      assigned to the alias or the alias doesn't exist.


  .. method:: delete()
    
    Deletes the alias with all its destinations.

    :rtype: :obj:`None`
    :raise VirtualMailManager.errors.AliasError: if the alias doesn't exist.


  .. method:: get_destinations()

    Returns an iterator for all destinations (``EmailAddress`` instances) of
    the alias.

    :rtype: :obj:`listiterator`
    :raise VirtualMailManager.errors.AliasError: if the alias doesn't exist.