Homec4science
Diffusion invenio-infoscience (maint-2.1) Browse

R3600/modules/miscutil/lib/settings.py
0a01f74c4d74maint-2.1

Last Change
Raw File

settings.py
View Options

# -*- coding: utf-8 -*-
##
## This file is part of Invenio.
## Copyright (C) 2012 CERN.
##
## Invenio is free software; you can redistribute it and/or
## modify it under the terms of the GNU General Public License as
## published by the Free Software Foundation; either version 2 of the
## License, or (at your option) any later version.
##
## Invenio 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
## General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with Invenio; if not, write to the Free Software Foundation, Inc.,
## 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
"""
Invenio utilities to settings manipulation.
"""
from invenio.sqlalchemyutils import db
from invenio.websession_model import User
from invenio.webuser_flask import current_user, login_user, logout_user
class Storage(object):
"""
Generic storage engine for settings.
It allows to load and store key-value data only for specified keys.
"""
_keys = []
_data = {}
def __init__(self, keys):
"""
@param keys: allowed keys in the storage.
"""
self._keys = keys
def load(self, default=None):
"""
Loads values from storage system.
@return: Filtered dictionary and for non-existing keys returns `default`
"""
return dict((k, self._data.get(k, default)) for k in self._keys)
def store(self, data):
"""
Stores data in storage system.
@param data: multivalue dictionary.
For keys with only one value in the value list it stores this single
value instead of whole list.
"""
self._data.update(map(
lambda (k,v): (k, v[0] if len(v) == 1 else v),
filter(
lambda (k,v): k in self._keys,
data.lists()
)))
def save(self):
"""
Implement this method for persistent storage system.
"""
pass
class UserSettingsStorage(Storage):
"""
Storage engine using User settings object for data persistency.
"""
def __init__(self, keys, attr=None):
self._keys = keys
self._user = User.query.get(current_user.get_id())
self._attr = attr
if self._attr is None:
self._data = dict(self._user.settings)
else:
self._data = dict(self._user.settings.get(self._attr, {}))
def save(self):
data = dict(self._user.settings)
if self._attr is None:
data.update(self.load())
else:
values = data.get(self._attr, {})
values.update(self.load())
data[self._attr] = values
self._user.settings = data
db.session.merge(self._user)
db.session.commit()
current_user.reload()
def UserSettingsAttributeStorage(attr):
"""
Class factory for 2nd level user settings.
"""
return lambda self, key: UserSettingsStorage(key, attr)
def ModelSettingsStorageBuilder(query_builder):
"""
Class factory for database model storage system.
@param query_builder: callable that returns valid SQLAlchemy model instance.
"""
class ModelSettingsStorage(Storage):
def __init__(self, keys):
self._keys = keys
self._model = query_builder()
self._data = dict(self._model)
def save(self):
for (k,v) in self.load().items():
setattr(self._model, k, v)
db.session.merge(self._model)
db.session.commit()
return ModelSettingsStorage
class Settings(object):
"""
Settings object designed for user account page with widgets.
"""
keys = [] ## list of valid setting keys
storage_builder = Storage ## storage builder factory method
form_builder = None ## form builder factory method
def __init__(self):
## initializes storage system
self.storage = self.storage_builder(self.keys)
def load(self):
"""
Loads data from storage system.
"""
return self.storage.load()
def store(self, data):
"""
Stores data in storage system.
"""
self.storage.store(data)
def save(self):
"""
Commit data in persistent storage system.
"""
self.storage.save()
c4science · Help