def test_registered_with_other_uow_fails(self):
ent = _MyEntity()
uow = UnitOfWork()
uow.register_new(_MyEntity, ent)
with self.assert_raises(ValueError) as cm1:
self._uow.register_new(_MyEntity, ent)
msg1 = 'Trying to register an entity that has been'
self.assert_true(cm1.exception.message.startswith(msg1))
with self.assert_raises(ValueError) as cm2:
self._uow.unregister(_MyEntity, ent)
msg2 = 'Trying to unregister an entity that has been'
self.assert_true(cm2.exception.message.startswith(msg2))
class UnitOfWorkTestCase(Pep8CompliantTestCase):
def set_up(self):
self._uow = UnitOfWork()
def test_basics(self):
ent = _MyEntity()
self._uow.register_new(_MyEntity, ent)
self.assert_equal(EntityStateManager.get_state(ent),
OBJECT_STATES.NEW)
self.assert_equal([item[1] for item in self._uow.iterator()],
[ent])
self.assert_equal(list(self._uow.get_new(_MyEntity)), [ent])
self._uow.mark_clean(_MyEntity, ent)
self.assert_equal(list(self._uow.get_clean(_MyEntity)), [ent])
self._uow.mark_dirty(_MyEntity, ent)
self.assert_equal(list(self._uow.get_dirty(_MyEntity)), [ent])
self._uow.mark_deleted(_MyEntity, ent)
self.assert_equal(list(self._uow.get_deleted(_MyEntity)), [ent])
self._uow.unregister(_MyEntity, ent)
self.assert_equal(list(self._uow.iterator()), [])
self._uow.reset()
def test_get_state_unregistered_fails(self):
ent = _MyEntity()
with self.assert_raises(ValueError) as cm:
EntityStateManager.get_state(ent)
msg = 'Trying to get the state of an unregistered entity'
self.assert_true(cm.exception.message.startswith(msg))
def test_release_unregistered_fails(self):
ent = _MyEntity()
with self.assert_raises(ValueError) as cm:
self._uow.unregister(_MyEntity, ent)
msg = 'Trying to unregister an entity that has not been'
self.assert_true(cm.exception.message.startswith(msg))
def test_registered_with_other_uow_fails(self):
ent = _MyEntity()
uow = UnitOfWork()
uow.register_new(_MyEntity, ent)
with self.assert_raises(ValueError) as cm1:
self._uow.register_new(_MyEntity, ent)
msg1 = 'Trying to register an entity that has been'
self.assert_true(cm1.exception.message.startswith(msg1))
with self.assert_raises(ValueError) as cm2:
self._uow.unregister(_MyEntity, ent)
msg2 = 'Trying to unregister an entity that has been'
self.assert_true(cm2.exception.message.startswith(msg2))
def test_mark_deleted_as_clean(self):
ent = _MyEntity()
self._uow.register_new(_MyEntity, ent)
self._uow.mark_deleted(_MyEntity, ent)
with self.assert_raises(ValueError) as cm:
self._uow.mark_clean(_MyEntity, ent)
msg = 'Invalid state transition'
self.assert_true(cm.exception.message.startswith(msg))
class MemorySession(object):
"""
Session object.
The session
* Holds a Unit Of Work;
* Serves as identity and slug map;
* Performs synchronized commit on repository;
* Sets up data manager to hook into transaction.
"""
def __init__(self, repository):
self.__repository = repository
self.__unit_of_work = UnitOfWork()
self.__cache_mgr = EntityCacheManager(repository,
self.__load_from_repository)
self.__need_datamanager_setup = repository.join_transaction is True
def commit(self):
with self.__repository.lock:
self.__repository.commit(self.__unit_of_work)
self.__unit_of_work.reset()
self.__cache_mgr.reset()
def rollback(self):
# for ent_cls, ent, state in self.__unit_of_work.iterator():
# if state == OBJECT_STATES.DIRTY:
# cache = self.__cache_mgr[ent_cls]
# cache.replace(self.__repository.get_by_id(ent_cls, ent.id))
self.__unit_of_work.reset()
self.__cache_mgr.reset()
def add(self, entity_class, entity):
"""
Adds the given entity of the given entity class to the session.
At the point an entity is added, it must not have an ID or a slug
of another entity that is already in the session. However, both the ID
and the slug may be ``None`` values.
"""
cache = self.__cache_mgr[entity_class]
if not entity.id is None and cache.has_id(entity.id):
raise ValueError('Duplicate entity ID "%s".' % entity.id)
if not entity.slug is None and cache.has_slug(entity.slug):
raise ValueError('Duplicate entity slug "%s".' % entity.slug)
if self.__need_datamanager_setup:
self.__setup_datamanager()
if entity.id is None:
entity.id = new_entity_id()
self.__unit_of_work.register_new(entity_class, entity)
cache.add(entity)
def remove(self, entity_class, entity):
"""
Removes the given entity of the given entity class from the session.
"""
if self.__need_datamanager_setup:
self.__setup_datamanager()
self.__unit_of_work.mark_deleted(entity_class, entity)
cache = self.__cache_mgr[entity_class]
cache.remove(entity)
def replace(self, entity_class, entity):
"""
Replaces the entity in the session with the same ID as the given
entity with the latter.
:raises ValueError: If the session does not contain an entity with
the same ID as the ID of the given :param:`entity`.
"""
if self.__need_datamanager_setup:
self.__setup_datamanager()
found_ent = self.get_by_id(entity_class, entity.id)
if found_ent is None:
raise ValueError('Entity with ID %s to replace not found.'
% entity.id)
self.__unit_of_work.unregister(entity_class, found_ent)
self.__unit_of_work.register_new(entity_class, entity)
cache = self.__cache_mgr[entity_class]
cache.replace(entity)
def get_by_id(self, entity_class, entity_id):
"""
Retrieves the entity for the specified entity class and ID.
"""
if self.__need_datamanager_setup:
self.__setup_datamanager()
return self.__cache_mgr[entity_class].get_by_id(entity_id)
def get_by_slug(self, entity_class, entity_slug):
"""
Retrieves the entity for the specified entity class and slug.
When the entity is not found in the cache, it may have been added
with an undefined slug and is looked up in the list of pending NEW
entities.
"""
if self.__need_datamanager_setup:
self.__setup_datamanager()
ent = self.__cache_mgr[entity_class].get_by_slug(entity_slug)
if ent is None:
for new_ent in self.__unit_of_work.get_new(entity_class):
if new_ent.slug == entity_slug:
ent = new_ent
break
return ent
def iterator(self, entity_class):
"""
Iterates over all entities of the given class in the repository,
adding all entities that are not in the session.
"""
if self.__need_datamanager_setup:
self.__setup_datamanager()
cache = self.__cache_mgr[entity_class]
return cache.iterator()
def get_all(self, entity_class):
"""
Returns a list of all entities of the given class in the repository.
"""
return list(self.iterator(entity_class))
def __setup_datamanager(self):
dm = DataManager(self)
trx = transaction.get()
trx.join(dm)
self.__need_datamanager_setup = False
def __load_from_repository(self, entity_class):
ents = []
for repo_ent in self.__repository.iterator(entity_class):
ent = self.__unit_of_work.register_clean(entity_class,
repo_ent)
ents.append(ent)
return ents
class MemorySession(object):
"""
Session object.
The session
* Holds a Unit Of Work;
* Serves as identity and slug map;
* Performs synchronized commit on repository;
* Sets up data manager to hook into transaction.
"""
def __init__(self, repository):
self.__repository = repository
self.__unit_of_work = UnitOfWork()
self.__cache_mgr = EntityCacheManager(repository,
self.__load_from_repository)
self.__need_datamanager_setup = repository.join_transaction is True
def commit(self):
with self.__repository.lock:
self.__repository.commit(self.__unit_of_work)
self.__unit_of_work.reset()
self.__cache_mgr.reset()
def rollback(self):
# for ent_cls, ent, state in self.__unit_of_work.iterator():
# if state == OBJECT_STATES.DIRTY:
# cache = self.__cache_mgr[ent_cls]
# cache.replace(self.__repository.get_by_id(ent_cls, ent.id))
self.__unit_of_work.reset()
self.__cache_mgr.reset()
def add(self, entity_class, entity):
"""
Adds the given entity of the given entity class to the session.
At the point an entity is added, it must not have an ID or a slug
of another entity that is already in the session. However, both the ID
and the slug may be ``None`` values.
"""
cache = self.__cache_mgr[entity_class]
if not entity.id is None and cache.has_id(entity.id):
raise ValueError('Duplicate entity ID "%s".' % entity.id)
if not entity.slug is None and cache.has_slug(entity.slug):
raise ValueError('Duplicate entity slug "%s".' % entity.slug)
if self.__need_datamanager_setup:
self.__setup_datamanager()
if entity.id is None:
entity.id = new_entity_id()
self.__unit_of_work.register_new(entity_class, entity)
cache.add(entity)
def remove(self, entity_class, entity):
"""
Removes the given entity of the given entity class from the session.
"""
if self.__need_datamanager_setup:
self.__setup_datamanager()
self.__unit_of_work.mark_deleted(entity_class, entity)
cache = self.__cache_mgr[entity_class]
cache.remove(entity)
def replace(self, entity_class, entity):
"""
Replaces the entity in the session with the same ID as the given
entity with the latter.
:raises ValueError: If the session does not contain an entity with
the same ID as the ID of the given :param:`entity`.
"""
if self.__need_datamanager_setup:
self.__setup_datamanager()
found_ent = self.get_by_id(entity_class, entity.id)
if found_ent is None:
raise ValueError('Entity with ID %s to replace not found.' %
entity.id)
self.__unit_of_work.unregister(entity_class, found_ent)
self.__unit_of_work.register_new(entity_class, entity)
cache = self.__cache_mgr[entity_class]
cache.replace(entity)
def get_by_id(self, entity_class, entity_id):
"""
Retrieves the entity for the specified entity class and ID.
"""
if self.__need_datamanager_setup:
self.__setup_datamanager()
return self.__cache_mgr[entity_class].get_by_id(entity_id)
def get_by_slug(self, entity_class, entity_slug):
"""
Retrieves the entity for the specified entity class and slug.
When the entity is not found in the cache, it may have been added
with an undefined slug and is looked up in the list of pending NEW
entities.
"""
if self.__need_datamanager_setup:
self.__setup_datamanager()
ent = self.__cache_mgr[entity_class].get_by_slug(entity_slug)
if ent is None:
for new_ent in self.__unit_of_work.get_new(entity_class):
if new_ent.slug == entity_slug:
ent = new_ent
break
return ent
def iterator(self, entity_class):
"""
Iterates over all entities of the given class in the repository,
adding all entities that are not in the session.
"""
if self.__need_datamanager_setup:
self.__setup_datamanager()
cache = self.__cache_mgr[entity_class]
return cache.iterator()
def get_all(self, entity_class):
"""
Returns a list of all entities of the given class in the repository.
"""
return list(self.iterator(entity_class))
def __setup_datamanager(self):
dm = DataManager(self)
trx = transaction.get()
trx.join(dm)
self.__need_datamanager_setup = False
def __load_from_repository(self, entity_class):
ents = []
for repo_ent in self.__repository.iterator(entity_class):
ent = self.__unit_of_work.register_clean(entity_class, repo_ent)
ents.append(ent)
return ents