Argument store added to updateEntityProperties.
This argument determines if an entity should be stored in the data model after its properties are updated.
It may be useful, for example, along with tasks (Task Queue API). One may want to make some modifications to an entity during execution of a task, but the developer is sure that at least one new task, which also wants to modify the entity, will be queued, so he or she can just update the entity without saving the changes to the data model, set the entity in memcache and the following task (which is to be executed very shortly) is to retrive the current entity from the memcache (without any expensive calls to the actual data model).
#!/usr/bin/python2.5
#
# Copyright 2009 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.
"""Mentor (Model) query functions.
"""
__authors__ = [
'"Lennard de Rijk" <ljvderijk@gmail.com>',
]
from google.appengine.ext import db
from soc.logic.models import role
from soc.logic.models import organization as org_logic
import soc.models.mentor
import soc.models.role
DEF_ALREADY_MENTORING_RPOJECT_MSG = "This Mentor is mentoring a Student "\
"Project and can therefore not be resigned. Please assign another Mentor."
DEF_ALREADY_MENTORING_PROPOSAL_MSG = "This Mentor is mentoring a Student "\
"Proposal and can therefore not be resigned. Please assign another Mentor."
class Logic(role.Logic):
"""Logic methods for the Mentor model.
"""
def __init__(self, model=soc.models.mentor.Mentor,
base_model=soc.models.role.Role, scope_logic=org_logic,
role_name='mentor', disallow_last_resign=False):
"""Defines the name, key_name and model for this entity.
"""
super(Logic, self).__init__(model=model, base_model=base_model,
scope_logic=scope_logic,
role_name=role_name,
disallow_last_resign=disallow_last_resign)
def canResign(self, entity):
"""Checks if the Mentor is able to resign.
Checks if there are no Student Proposals or Student Projects that
have this mentor assigned to it.
Args:
entity: a Mentor entity
"""
from soc.logic.models.student_project import logic as \
student_project_logic
from soc.logic.models.student_proposal import logic as \
student_proposal_logic
fields = {'mentor': entity}
student_project_entity = student_project_logic.getForFields(fields,
unique=True)
if student_project_entity:
return DEF_ALREADY_MENTORING_RPOJECT_MSG
student_proposal_entity = student_proposal_logic.getForFields(fields,
unique=True)
if student_proposal_entity:
return DEF_ALREADY_MENTORING_PROPOSAL_MSG
return super(Logic, self).canResign(entity)
def _updateField(self, entity, entity_properties, name):
"""Called when the fields of the mentor are updated
When status is changed to invalid, removes the Mentor from all Student
Proposals possible mentor lists.
"""
from soc.logic.models.student_proposal import logic \
as student_proposal_logic
value = entity_properties[name]
if name == 'status' and value != entity.status and value == 'invalid':
fields = {'org': entity.scope}
# TODO make this work for more then 1000 entities
proposals_query = student_proposal_logic.getQueryForFields(fields)
# store all updated proposals
changed = []
for proposal in proposals_query:
if proposal.possible_mentors.count(entity.key()):
# remove from list and add to changed
proposal.possible_mentors.remove(entity.key())
changed.append(proposal)
# store all changed proposals
db.put(changed)
return super(Logic, self)._updateField(entity, entity_properties, name)
def getRoleLogicsToNotifyUponNewRequest(self):
"""Returns a list with OrgAdmin logic which can be used to notify all
appropriate Organization Admins.
"""
from soc.logic.models.org_admin import logic as org_admin_logic
return [org_admin_logic]
logic = Logic()