Source code for heat.engine.conditions

#
#    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.

import collections

from heat.common.i18n import _

from heat.common import exception
from heat.engine import function


_in_progress = object()


[docs]class Conditions(object): def __init__(self, conditions_dict): assert isinstance(conditions_dict, collections.abc.Mapping) self._conditions = conditions_dict self._resolved = {}
[docs] def validate(self): for name, cond in self._conditions.items(): self._check_condition_type(name, cond) function.validate(cond)
def _resolve(self, condition_name): resolved = function.resolve(self._conditions[condition_name]) self._check_condition_type(condition_name, resolved) return resolved def _check_condition_type(self, condition_name, condition_defn): if not isinstance(condition_defn, (bool, function.Function)): msg_data = {'cd': condition_name, 'definition': condition_defn} message = _('The definition of condition "%(cd)s" is invalid: ' '%(definition)s') % msg_data raise exception.StackValidationFailed( error='Condition validation error', message=message)
[docs] def is_enabled(self, condition_name): if condition_name is None: return True if isinstance(condition_name, bool): return condition_name if not (isinstance(condition_name, str) and condition_name in self._conditions): raise ValueError(_('Invalid condition "%s"') % condition_name) if condition_name not in self._resolved: self._resolved[condition_name] = _in_progress self._resolved[condition_name] = self._resolve(condition_name) result = self._resolved[condition_name] if result is _in_progress: message = _('Circular definition for condition ' '"%s"') % condition_name raise exception.StackValidationFailed( error='Condition validation error', message=message) return result
def __repr__(self): return 'Conditions(%r)' % self._conditions