# GNU MediaGoblin -- federated, autonomous media hosting
# Copyright (C) 2011, 2012 MediaGoblin contributors. See AUTHORS.
#
# This program 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.
#
# This program 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 this program. If not, see .
from sqlalchemy.ext.mutable import Mutable
from sqlalchemy.types import TypeDecorator, Unicode, TEXT
import json
class PathTupleWithSlashes(TypeDecorator):
"Represents a Tuple of strings as a slash separated string."
impl = Unicode
def process_bind_param(self, value, dialect):
if value is not None:
if len(value) == 0:
value = None
else:
value = '/'.join(value)
return value
def process_result_value(self, value, dialect):
if value is not None:
value = tuple(value.split('/'))
return value
# The following two classes and only these two classes is in very
# large parts based on example code from sqlalchemy.
#
# The original copyright notice and license follows:
# Copyright (C) 2005-2011 the SQLAlchemy authors and contributors
#
# This module is part of SQLAlchemy and is released under
# the MIT License: http://www.opensource.org/licenses/mit-license.php
#
class JSONEncoded(TypeDecorator):
"Represents an immutable structure as a json-encoded string."
impl = TEXT
def process_bind_param(self, value, dialect):
if value is not None:
value = json.dumps(value)
return value
def process_result_value(self, value, dialect):
if value is not None:
value = json.loads(value)
return value
class MutationDict(Mutable, dict):
@classmethod
def coerce(cls, key, value):
"Convert plain dictionaries to MutationDict."
if not isinstance(value, MutationDict):
if isinstance(value, dict):
return MutationDict(value)
# this call will raise ValueError
return Mutable.coerce(key, value)
else:
return value
def __setitem__(self, key, value):
"Detect dictionary set events and emit change events."
dict.__setitem__(self, key, value)
self.changed()
def __delitem__(self, key):
"Detect dictionary del events and emit change events."
dict.__delitem__(self, key)
self.changed()