def enqueue_post_task(shard, post_ids, new_topic=None):
"""Enqueues a task to post a new task on a shard."""
params_dict = dict(shard=shard, post_ids=post_ids)
if new_topic is not None:
params_dict.update(new_topic=new_topic)
taskqueue.Task(
method='PULL',
tag=str(shard),
params=params_dict,
).add(config.pending_queue, transactional=ndb.in_transaction())
def update_read_state(topic_dict, user_id):
"""Updates a user's read state for a given set of topics.
Will inherit transaction state on user_id's LoginRecord if this is
called from within an existing transition.
Args:
topic_dict: Maps topic shard IDs to the new sequence number to assign
for that shard.
user_id: User ID that is being updated.
"""
# TODO(bslatkin): Consider validating the topic list provided here
# to ensure they are actually associated with the current logged-in shard.
# The possible damage here is restricted to the user so we don't care much.
read_state_keys = [
ndb.Key(models.LoginRecord._get_kind(), user_id,
models.ReadState._get_kind(), topic)
for topic in topic_dict]
def txn():
read_state_list = ndb.get_multi(read_state_keys)
to_put = []
for key, read_state in zip(read_state_keys, read_state_list):
next_read_sequence = topic_dict[key.id()]
if read_state is None:
read_state = models.ReadState(key=key)
read_state.last_read_sequence = next_read_sequence
else:
read_state.last_read_sequence = max(
read_state.last_read_sequence, next_read_sequence)
to_put.append(read_state)
ndb.put_multi(to_put)
if ndb.in_transaction():
txn()
else:
ndb.transaction(txn)