#===============================================================================
# Copyright 2005-2009, Tassos Koutsovassilis
#
# This file is part of Porcupine.
# Porcupine is free software; you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 2.1 of the License, or
# (at your option) any later version.
# Porcupine is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
# You should have received a copy of the GNU Lesser General Public License
# along with Porcupine; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#===============================================================================
"Base database index class"
from porcupine.core import persist,cache
from porcupine.utils.db import pack_value
_cache = cache.Cache(20)
class BaseIndex(object):
def __init__(self, name, unique):
self.unique = unique
self.name = name
self.callback = self._get_callback()
def _get_callback(self):
def callback(key, value):
item = _cache.get(value, persist.loads(value))
index_value = None
if hasattr(item, self.name):
attr = getattr(item, self.name)
if attr.__class__.__module__ != '__builtin__':
attr = attr.value
index_value = pack_value(attr)
_cache[value] = item
return index_value
return callback
def close(self):
raise NotImplementedError
|