VirtualMailManager/maillocation.py
author martin f. krafft <madduck@madduck.net>
Sat, 07 Apr 2012 00:45:57 +0200
branchv0.6.x
changeset 492 e5c2b3647971
parent 450 fd4aa073015f
child 568 14abdd04ddf5
permissions -rw-r--r--
Modify address check query to obtain well-defined result The way in which UNION does not yield the desired result, because (a) UNION merges results and (b) the result order is undefined. This patch changes the query to select the counts as columns and hence provides a well-defined order.

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

    Virtual Mail Manager's maillocation module to handle Dovecot's
    mail_location setting for accounts.

"""

from VirtualMailManager.constants import MAILLOCATION_INIT
from VirtualMailManager.errors import MailLocationError as MLErr
from VirtualMailManager.pycompat import all


__all__ = ('MailLocation', 'known_format')

_ = lambda msg: msg
_format_info = {
    'maildir': dict(dovecot_version=0x10000f00, postfix=True),
    'mdbox': dict(dovecot_version=0x20000b05, postfix=False),
    'sdbox': dict(dovecot_version=0x20000c03, postfix=False),
}


class MailLocation(object):
    """Class to handle mail_location relevant information."""
    __slots__ = ('_directory', '_mbfmt', '_mid', '_dbh')
    _kwargs = ('mid', 'mbfmt', 'directory')

    def __init__(self, dbh, **kwargs):
        """Creates a new MailLocation instance.

        Either the mid keyword or the mbfmt and directory keywords must be
        specified.

        Arguments:

        `dbh` : pyPgSQL.PgSQL.Connection
          A database connection for the database access.

        Keyword arguments:

        `mid` : int
          the id of a mail_location
        `mbfmt` : str
          the mailbox format of the mail_location. One out of: ``maildir``,
          ``sdbox`` and ``mdbox``.
        `directory` : str
          name of the mailbox root directory.
        """
        self._dbh = dbh
        self._directory = None
        self._mbfmt = None
        self._mid = 0

        for key in kwargs.iterkeys():
            if key not in self.__class__._kwargs:
                raise ValueError('unrecognized keyword: %r' % key)
        mid = kwargs.get('mid')
        if mid:
            assert isinstance(mid, (int, long))
            self._load_by_mid(mid)
        else:
            args = kwargs.get('mbfmt'), kwargs.get('directory')
            assert all(isinstance(arg, basestring) for arg in args)
            if args[0].lower() not in _format_info:
                raise MLErr(_(u"Unsupported mailbox format: '%s'") % args[0],
                            MAILLOCATION_INIT)
            directory = args[1].strip()
            if not directory:
                raise MLErr(_(u"Empty directory name"), MAILLOCATION_INIT)
            if len(directory) > 20:
                raise MLErr(_(u"Directory name is too long: '%s'") % directory,
                            MAILLOCATION_INIT)
            self._load_by_names(args[0].lower(), directory)

    def __str__(self):
        return u'%s:~/%s' % (self._mbfmt, self._directory)

    @property
    def directory(self):
        """The mail_location's directory name."""
        return self._directory

    @property
    def dovecot_version(self):
        """The required Dovecot version for this mailbox format."""
        return _format_info[self._mbfmt]['dovecot_version']

    @property
    def postfix(self):
        """`True` if Postfix supports this mailbox format, else `False`."""
        return _format_info[self._mbfmt]['postfix']

    @property
    def mbformat(self):
        """The mail_location's mailbox format."""
        return self._mbfmt

    @property
    def mail_location(self):
        """The mail_location, e.g. ``maildir:~/Maildir``"""
        return self.__str__()

    @property
    def mid(self):
        """The mail_location's unique ID."""
        return self._mid

    def _load_by_mid(self, mid):
        """Load mail_location relevant information by *mid*"""
        dbc = self._dbh.cursor()
        dbc.execute('SELECT format, directory FROM mailboxformat, '
                    'maillocation WHERE mid = %u AND '
                    'maillocation.fid = mailboxformat.fid' % mid)
        result = dbc.fetchone()
        dbc.close()
        if not result:
            raise ValueError('Unknown mail_location id specified: %r' % mid)
        self._mid = mid
        self._mbfmt, self._directory = result

    def _load_by_names(self, mbfmt, directory):
        """Try to load mail_location relevant information by *mbfmt* and
        *directory* name. If it fails goto _save()."""
        dbc = self._dbh.cursor()
        dbc.execute("SELECT mid FROM maillocation WHERE fid = (SELECT fid "
                    "FROM mailboxformat WHERE format = %s) AND directory = %s",
                    (mbfmt, directory))
        result = dbc.fetchone()
        dbc.close()
        if not result:
            self._save(mbfmt, directory)
        else:
            self._mid = result[0]
            self._mbfmt = mbfmt
            self._directory = directory

    def _save(self, mbfmt, directory):
        """Save a new mail_location in the database."""
        dbc = self._dbh.cursor()
        dbc.execute("SELECT nextval('maillocation_id')")
        mid = dbc.fetchone()[0]
        dbc.execute("INSERT INTO maillocation (fid, mid, directory) VALUES ("
                    "(SELECT fid FROM mailboxformat WHERE format = %s), %s, "
                    "%s)",  (mbfmt, mid, directory))
        self._dbh.commit()
        dbc.close()
        self._mid = mid
        self._mbfmt = mbfmt
        self._directory = directory


def known_format(mbfmt):
    """Checks if the mailbox format *mbfmt* is known, returns bool."""
    return mbfmt.lower() in _format_info

del _