Source code for renku.core.models.locals
# -*- coding: utf-8 -*-
#
# Copyright 2020 - 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.
"""Manage local contexts."""
from contextlib import contextmanager
import attr
from werkzeug.local import LocalStack
_current_reference = LocalStack()
current_reference = _current_reference()
@contextmanager
def with_reference(path):
"""Manage reference stack."""
_current_reference.push(path)
yield
if path != _current_reference.pop():
raise RuntimeError('current_reference has been modified')
def has_reference():
"""Check if the current reference is bounded."""
return _current_reference.top is not None
@attr.s(cmp=False)
class ReferenceMixin:
"""Define an automatic ``__reference__`` attribute."""
__source__ = attr.ib(init=False, kw_only=True, repr=False, default=None)
__reference__ = attr.ib(init=False, kw_only=True, repr=False)
@__reference__.default
def default_reference(self):
"""Create a default reference path."""
return current_reference._get_current_object() if has_reference(
) else None