Introduce dynamic scope_path regexps
Instead of relying on scope_path's being "one slash deep", we should
instead allow for either:
1. scope_paths that have a pre-defined depth
2. scope_paths that can be arbitrarily deep
We achieve 1 by setting an entities scope_logic to another logic
module. We then recursively call getScopeDepth until we get to the
topmost entity (that is, an unscoped entity).
A little different is the solution to 2, since some entities can have
an arbitrarily deep scope (such as Documents), we need to have some
way of signaling this to getScopePattern. A clean solution is to
return None, rather than a number. If None is returned, the
SCOPE_PATH_ARG_PATTERN is returned as regexp instead, which will
match an arbitrarily deeply nested scope.
The solution for 2 requires that we return None somewhere in the
scope_logic chain, the most straight forward method to do so is to
override getScopeDepth anywhere such a scope is needed and make it
return None. A more elegant solution however, is to set the
scope_logic to that module in all entities that require it.
Patch by: Sverre Rabbelier
#!/usr/bin/python2.5
#
# Copyright 2008 the Melange authors.
#
# 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.
"""Group (Model) query functions.
"""
__authors__ = [
'"Sverre Rabbelier" <sverre@rabbelier.nl>',
]
from soc.logic.models import base
import soc.models.group
class Logic(base.Logic):
"""Logic methods for the Group model.
"""
def __init__(self, model=soc.models.group.Group,
base_model=None, scope_logic=None):
"""Defines the name, key_name and model for this entity.
"""
super(Logic, self).__init__(model, base_model=base_model,
scope_logic=scope_logic)
def getKeyValues(self, entity):
"""Extracts the key values from entity and returns them.
The default implementation for Groups assumes that the Group is site-wide
and thus has no scope. Such Groups include Sponsors and Clubs. Any
Group that exists per-Program or per-Year will need to override this
method.
Args:
entity: the entity from which to extract the key values
"""
return [entity.link_id]
def getKeyValuesFromFields(self, fields):
"""Extracts the key values from a dict and returns them.
The default implementation for Groups assumes that the Group is site-wide
and thus has no scope. Such Groups include Sponsors and Clubs. Any
Group that exists per-Program or per-Year will need to override this
method.
Args:
fields: the dict from which to extract the key values
"""
return [fields['link_id']]
def getKeyFieldNames(self):
"""Returns an array with the names of the Key Fields.
The default implementation for Groups assumes that the Group is site-wide
and thus has no scope. Such Groups include Sponsors and Clubs. Any
Group that exists per-Program or per-Year will need to override this
method.
"""
return ['link_id']
def isDeletable(self, entity):
"""Returns whether the specified Group entity can be deleted.
Generically, a Group can always be deleted. Subclasses of group.Logic
should add their own deletion prerequisites.
Args:
entity: an existing Group entity in the Datastore
"""
return True
logic = Logic()