diff -r 492c179094c9 -r f180ead60568 VirtualMailManager/catchall.py --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/VirtualMailManager/catchall.py Mon Apr 09 18:10:56 2012 +0200 @@ -0,0 +1,171 @@ +# -*- coding: UTF-8 -*- +# Copyright (c) 2012 martin f. krafft +# See COPYING for distribution information. +""" + VirtualMailManager.catchall + ~~~~~~~~~~~~~~~~~~~~~~~~~~~ + + Virtual Mail Manager's CatchallAlias class to manage domain catch-all + aliases. + + This is heavily based on (more or less a copy of) the Alias class, because + fundamentally, catchall aliases are aliases, but without a localpart. + While Alias could potentially derive from CatchallAlias to reuse some of + the functionality, it's probably not worth it. I found no sensible way to + derive CatchallAlias from Alias, or at least none that would harness the + powers of polymorphism. + + Yet, we reuse the AliasError exception class, which makes sense. +""" + +from VirtualMailManager.domain import get_gid +from VirtualMailManager.emailaddress import \ + EmailAddress, DestinationEmailAddress as DestAddr +from VirtualMailManager.errors import AliasError as AErr +from VirtualMailManager.ext.postconf import Postconf +from VirtualMailManager.pycompat import all +from VirtualMailManager.constants import \ + ALIAS_EXCEEDS_EXPANSION_LIMIT, NO_SUCH_ALIAS, NO_SUCH_DOMAIN + + +_ = lambda msg: msg +cfg_dget = lambda option: None + + +class CatchallAlias(object): + """Class to manage domain catch-all aliases.""" + __slots__ = ('_domain', '_dests', '_gid', '_dbh') + + def __init__(self, dbh, domain): + self._domain = domain + self._dbh = dbh + self._gid = get_gid(self._dbh, self._addr.domain) + if not self._gid: + raise AErr(_(u"The domain '%s' does not exist.") % + self._addr.domainname, NO_SUCH_DOMAIN) + self._dests = [] + + self._load_dests() + + def _load_dests(self): + """Loads all known destination addresses into the _dests list.""" + dbc = self._dbh.cursor() + dbc.execute('SELECT destination FROM catchall WHERE gid = %s', + self._gid) + dests = dbc.fetchall() + if dbc.rowcount > 0: + self._dests.extend(DestAddr(dest[0], self._dbh) for dest in dests) + dbc.close() + + def _check_expansion(self, count_new): + """Checks the current expansion limit of the alias.""" + postconf = Postconf(cfg_dget('bin.postconf')) + limit = long(postconf.read('virtual_alias_expansion_limit')) + dcount = len(self._dests) + failed = False + if dcount == limit or dcount + count_new > limit: + failed = True + errmsg = _( +u"""Cannot add %(count_new)i new destination(s) to catchall alias for +domain '%(domain)s'. Currently this alias expands into %(count)i/%(limit)i +recipients. %(count_new)i additional destination(s) will render this alias +unusable. +Hint: Increase Postfix' virtual_alias_expansion_limit""") + elif dcount > limit: + failed = True + errmsg = _( +u"""Cannot add %(count_new)i new destination(s) to catchall alias for +domain '%(domain)s'. This alias already exceeds its expansion limit (%(count)i/%(limit)i). +So its unusable, all messages addressed to this alias will be bounced. +Hint: Delete some destination addresses.""") + if failed: + raise AErr(errmsg % {'domain': self._domain, 'count': dcount, + 'limit': limit, 'count_new': count_new}, + ALIAS_EXCEEDS_EXPANSION_LIMIT) + + def _delete(self, destination=None): + """Deletes a destination from the catchall alias, if ``destination`` + is not ``None``. If ``destination`` is None, the catchall alias with + all its destination addresses will be deleted. + + """ + dbc = self._dbh.cursor() + if not destination: + dbc.execute('DELETE FROM catchall WHERE gid = %s', self._gid) + else: + dbc.execute('DELETE FROM catchall WHERE gid = %s ' + 'AND destination = %s', (self._gid, str(destination))) + if dbc.rowcount > 0: + self._dbh.commit() + dbc.close() + + def __len__(self): + """Returns the number of destinations of the catchall alias.""" + return len(self._dests) + + @property + def domain(self): + """The Alias' domain.""" + return self._domain + + def add_destinations(self, destinations, warnings=None): + """Adds the `EmailAddress`es from *destinations* list to the + destinations of the catchall alias. + + Destinations, that are already assigned to the alias, will be + removed from *destinations*. When done, this method will return + a set with all destinations, that were saved in the database. + """ + destinations = set(destinations) + assert destinations and \ + all(isinstance(dest, EmailAddress) for dest in destinations) + if not warnings is None: + assert isinstance(warnings, list) + duplicates = destinations.intersection(set(self._dests)) + if duplicates: + destinations.difference_update(set(self._dests)) + if not warnings is None: + warnings.extend(duplicates) + if not destinations: + return destinations + self._check_expansion(len(destinations)) + dbc = self._dbh.cursor() + dbc.executemany("INSERT INTO catchall (gid, destination) " + "VALUES (%d, %%s)" % self._gid, + ((str(destination),) for destination in destinations)) + self._dbh.commit() + dbc.close() + self._dests.extend(destinations) + return destinations + + def del_destination(self, destination): + """Deletes the specified ``destination`` address from the catchall + alias.""" + assert isinstance(destination, EmailAddress) + if not self._dests: + raise AErr(_(u"There are no catchall aliases defined for " + u"domain '%s'.") % self._domain, NO_SUCH_ALIAS) + if not destination in self._dests: + raise AErr(_(u"The address '%(addr)s' is not a destination of " + u"the catchall alias for domain '%(domain)s'.") + % {'addr': destination, 'domain': self._domain}, + NO_SUCH_ALIAS) + self._delete(destination) + self._dests.remove(destination) + + def get_destinations(self): + """Returns an iterator for all destinations of the catchall alias.""" + if not self._dests: + raise AErr(_(u"There are no catchall aliases defined for " + u"domain '%s'.") % self._domain, NO_SUCH_ALIAS) + return iter(self._dests) + + def delete(self): + """Deletes all catchall destinations for the domain.""" + if not self._dests: + raise AErr(_(u"There are no catchall aliases defined for " + u"domain '%s'.") % self._domain, NO_SUCH_ALIAS) + self._delete() + del self._dests[:] + +del _, cfg_dget