weboob-devel/weboob/capabilities/base.py
2011-04-08 12:48:07 +02:00

156 lines
4.4 KiB
Python

# -*- coding: utf-8 -*-
# Copyright(C) 2010-2011 Christophe Benz, Romain Bignon
#
# This file is part of weboob.
#
# weboob is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# weboob 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 Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with weboob. If not, see <http://www.gnu.org/licenses/>.
from weboob.tools.misc import iter_fields
__all__ = ['FieldNotFound', 'IBaseCap', 'NotAvailable', 'NotLoaded',
'CapBaseObject']
class FieldNotFound(Exception):
def __init__(self, obj, field):
Exception.__init__(self,
u'Field "%s" not found for object %s' % (field, obj))
class NotAvailableMeta(type):
def __str__(self):
return unicode(self).decode('utf-8')
def __unicode__(self):
return u'Not available'
def __nonzero__(self):
return False
class NotAvailable(object):
__metaclass__ = NotAvailableMeta
class NotLoadedMeta(type):
def __str__(self):
return unicode(self).decode('utf-8')
def __unicode__(self):
return u'Not loaded'
def __nonzero__(self):
return False
class NotLoaded(object):
__metaclass__ = NotLoadedMeta
class IBaseCap(object):
pass
class CapBaseObject(object):
FIELDS = None
_attribs = None
def __init__(self, id, backend=None):
self.id = id
self.backend = backend
def add_field(self, name, type, value=NotLoaded):
"""
Add a field in list, which needs to be of type @type.
@param name [str] name of field
@param type [class] type accepted (can be a tuple of types)
@param value [object] value set to attribute (default is NotLoaded)
"""
if not isinstance(self.FIELDS, list):
self.FIELDS = []
self.FIELDS.append(name)
if self._attribs is None:
self._attribs = {}
self._attribs[name] = self._AttribValue(type, value)
def __iscomplete__(self):
"""
Return True if the object is completed.
It is usefull when the object is a field of an other object which is
going to be filled.
The default behavior is to iter on fields (with iter_fields) and if
a field is NotLoaded, return False.
"""
for key, value in self.iter_fields():
if value is NotLoaded:
return False
return True
def iter_fields(self):
"""
Iterate on the FIELDS keys and values.
Can be overloaded to iterate on other things.
@return [iter(key,value)] iterator on key, value
"""
if self.FIELDS is None:
yield 'id', self.id
for key, value in iter_fields(self):
if key not in ('id', 'backend','FIELDS'):
yield key, value
else:
yield 'id', self.id
for attrstr in self.FIELDS:
yield attrstr, getattr(self, attrstr)
def __eq__(self, obj):
if isinstance(obj, CapBaseObject):
return self.backend == obj.backend and self.id == obj.id
else:
return False
class _AttribValue(object):
def __init__(self, type, value):
self.type = type
self.value = value
def __getattr__(self, name):
if self._attribs is not None and name in self._attribs:
return self._attribs[name].value
else:
raise AttributeError, "'%s' object has no attribute '%s'" % (
self.__class__.__name__, name)
def __setattr__(self, name, value):
try:
attr = (self._attribs or {})[name]
except KeyError:
object.__setattr__(self, name, value)
else:
if not isinstance(value, attr.type) and \
value is not NotLoaded and \
value is not NotAvailable and \
value is not None:
raise ValueError(
'Value for "%s" needs to be of type %r, not %r' % (
name, attr.type, type(value)))
attr.value = value