# -*- coding: utf-8 -*-
#
# Copyright 2018-2022- Swiss Data Science Center (SDSC)
# A partnership between École Polytechnique Fédérale de Lausanne (EPFL) and
# Eidgenössische Technische Hochschule Zürich (ETHZ).
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Base Renku persistent class."""
import persistent
[docs]class Persistent(persistent.Persistent):
"""Base Persistent class for renku classes.
Subclasses are assumed to be immutable once persisted to the database. If a class shouldn't be immutable then
subclass it directly from persistent.Persistent.
"""
_v_immutable = False
[docs] def reassign_oid(self):
"""Reassign ``oid`` (after assigning a new identifier for example)."""
from renku.infrastructure.database import Database
if self._p_jar is not None:
self._p_jar.remove_from_cache(self)
self._p_oid = None
self._p_oid = Database.generate_oid(self)
@property
def immutable(self):
"""Return if object is immutable."""
return self._v_immutable
[docs] def freeze(self):
"""Set immutable property."""
self._v_immutable = True
[docs] def unfreeze(self):
"""Allows modifying an immutable object.
Don't make an object mutable unless the intention is to drop the changes or modify the object in-place. Modified
objects will be updated in-place which results in a binary diff when persisted. Normally, we want to create a
mutable copy and persist it as a new object.
"""
self._v_immutable = False
def __setattr__(self, key, value):
if self._v_immutable and key != "__weakref__" and not key.startswith("_p_") and not key.startswith("_v_"):
raise RuntimeError(f"Cannot modify immutable object {self}.{key}")
super().__setattr__(key, value)
@property
def __name__(self):
return self.__class__.__name__