def _class_from_path(self, task_path):
"""Return the task class given a task's path.
:param task_path: string for a class, e.g., mytask.MyTask
:return:
"""
if task_path not in self._task_mapper:
task_class = utils.class_import_from_path(task_path)
self._task_mapper[task_path] = task_class
return self._task_mapper[task_path]
def _class_from_path(self, task_path):
"""Return the task class given a task's path.
:param task_path: string for a class, e.g., mytask.MyTask
:return:
"""
if task_path not in self._task_mapper:
task_class = utils.class_import_from_path(task_path)
self._task_mapper[task_path] = task_class
return self._task_mapper[task_path]
def __init__(self, queue=None, body=''):
"""Constructor.
:param queue:
:param body: string for message body
"""
message.RawMessage.__init__(self, queue=queue, body=body)
# Lazily instantiate the task mapper.
if not self._task_mapper:
self._task_mapper = {k: utils.class_import_from_path(v)
for k, v in six.iteritems(settings.TASK_MAPPER)}
def __init__(self):
"""Initialize a worker instance."""
self._consumer = consumer.Consumer()
queue_class = utils.class_import_from_path(settings.QUEUE_CLASS)
q_info = queue_info.QueueInfo(
config_file=settings.QUEUE_CONFIG,
sqs_talk=self._consumer,
queue_cls=queue_class)
queue_selector_class = utils.class_import_from_path(
settings.QUEUE_SELECTOR)
self._queue_selector = queue_selector_class(q_info)
# The worker will publish permanently failed tasks to a
# dead-letter-queue.
self._publisher = self._get_publisher()
# Track total messages processed.
self._total_messages_processed = 0
# Intialize queue variables used by each batch.
self._incomplete_messages = []
self._successful_messages = []
self._failed_messages = []
self._permanent_failures = []
self._batch_stop_time = time.time()
self._batch_queue = None
# Monitors whether the worker has been exposed to tasks and may
# have bloated in memory.
self._dirty = False
# Setup signal handling for cleanup.
for sig in SIGNALS_TO_HANDLE:
signal.signal(sig, self._cleanup_worker)
# Allow the client of this library to do any setup before
# starting the worker.
settings.ON_WORKER_STARTUP()
def __init__(self):
"""Initialize a worker instance."""
self._consumer = consumer.Consumer()
queue_class = utils.class_import_from_path(settings.QUEUE_CLASS)
q_info = queue_info.QueueInfo(
config_file=settings.QUEUE_CONFIG,
sqs_talk=self._consumer,
queue_cls=queue_class)
queue_selector_class = utils.class_import_from_path(
settings.QUEUE_SELECTOR)
self._queue_selector = queue_selector_class(q_info)
# The worker will publish permanently failed tasks to a
# dead-letter-queue.
self._publisher = publisher.Publisher()
# Track total messages processed.
self._total_messages_processed = 0
# Intialize queue variables used by each batch.
self._incomplete_messages = []
self._successful_messages = []
self._failed_messages = []
self._permanent_failures = []
self._batch_stop_time = time.time()
self._batch_queue = None
# Monitors whether the worker has been exposed to tasks and may
# have bloated in memory.
self._dirty = False
# Setup signal handling for cleanup.
for sig in SIGNALS_TO_HANDLE:
signal.signal(sig, self._cleanup_worker)
# Allow the client of this library to do any setup before
# starting the worker.
settings.ON_WORKER_STARTUP()
def publish(self,
task_class,
task_id,
payload,
current_retry_num=None,
current_failure_num=None,
delay_sec=None):
"""Publish the given task type to the queue with the provided payload.
:param obj task_class: class of the task that we are publishing.
:param str task_id: unique identifying string for this task.
:param dict payload: dictionary for the task payload.
:param int current_retry_num: current task retry count. If 0, this is
the first attempt to run the task.
:param int current_failure_num: current task failure count.
:param int delay_sec: time (in seconds) that a task should stay
in the queue before being released to consumers.
:raises: TaskTooChubbyException: This task is outrageously chubby.
The publisher of the task should handle this exception and
determine how to proceed.
"""
if delay_sec is not None and delay_sec > settings.SQS_MAX_TASK_DELAY_SEC:
raise exceptions.InvalidTaskDelayException(
'Invalid task delay_sec (%d > %d).' %
(delay_sec, settings.SQS_MAX_TASK_DELAY_SEC))
queue_class = utils.class_import_from_path(settings.QUEUE_CLASS)
q_info = queue_info.QueueInfo(settings.QUEUE_CONFIG, self, queue_class)
queue_obj = q_info.get_queue(task_class.queue)
if task_class.time_limit >= queue_obj.visibility_timeout_sec:
raise exceptions.InvalidTimeLimitTaskException(
'Invalid task time limit: %d >= %d from %s' %
(task_class.time_limit, queue_obj.visibility_timeout_sec,
settings.QUEUE_CONFIG))
sqs_queue = self._get_or_create_queue(queue_obj.name)
kale_msg = message.KaleMessage(task_class=task_class,
task_id=task_id,
payload=payload,
current_retry_num=current_retry_num,
current_failure_num=current_failure_num)
sqs_queue.send_message(MessageBody=kale_msg.encode(),
DelaySeconds=delay_sec or 1)
logger.debug('Published task. Task id: %s; Task name: %s' %
(task_id, '%s.%s' %
(task_class.__module__, task_class.__name__)))
def __init__(self, queue=None, body=''):
"""Constructor.
:param queue:
:param body: string for message body
"""
message.RawMessage.__init__(self, queue=queue, body=body)
# Lazily instantiate the task mapper.
if not self._task_mapper:
self._task_mapper = {
k: utils.class_import_from_path(v)
for k, v in settings.TASK_MAPPER.iteritems()
}
def publish(self, task_class, task_id, payload,
current_retry_num=None, delay_sec=None):
"""Publish the given task type to the queue with the provided payload.
:param obj task_class: class of the task that we are publishing.
:param str task_id: unique identifying string for this task.
:param dict payload: dictionary for the task payload.
:param int current_retry_num: current task retry count. If 0, this is
the first attempt to run the task.
:param int delay_sec: time (in seconds) that a task should stay
in the queue before being released to consumers.
:raises: TaskTooChubbyException: This task is outrageously chubby.
The publisher of the task should handle this exception and
determine how to proceed.
"""
if delay_sec > settings.SQS_MAX_TASK_DELAY_SEC:
raise exceptions.InvalidTaskDelayException(
'Invalid task delay_sec (%d > %d).' % (
delay_sec, settings.SQS_MAX_TASK_DELAY_SEC))
queue_class = utils.class_import_from_path(settings.QUEUE_CLASS)
q_info = queue_info.QueueInfo(settings.QUEUE_CONFIG, self, queue_class)
queue_obj = q_info.get_queue(task_class.queue)
if task_class.time_limit >= queue_obj.visibility_timeout_sec:
raise exceptions.InvalidTimeLimitTaskException(
'Invalid task time limit: %d >= %d from %s' % (
task_class.time_limit, queue_obj.visibility_timeout_sec,
settings.QUEUE_CONFIG))
queue = self._get_or_create_queue(queue_obj.name)
sqs_msg = message.KaleMessage.create_message(
task_class=task_class,
task_id=task_id,
payload=payload,
queue=queue,
current_retry_num=current_retry_num)
queue.write(sqs_msg, delay_seconds=delay_sec)
logger.info('Published task. Task id: %s; Task name: %s' % (
task_id, '%s.%s' % (task_class.__module__, task_class.__name__)))
def __init__(self,
sqs_message_id=None,
sqs_receipt_handle=None,
sqs_queue_name=None,
task_class=None,
task_name=None,
task_id=None,
payload=None,
current_retry_num=None,
enqueued_time=None,
publisher_data=None,
instantiate_task=False,
delete_func=None
):
"""Constructor.
:param task_class: Class of task.
:param task_name: Name of task. Required if task_class is not set.
:param task_id: Id of task.
:param payload: Payload holds the data that the task's run_task method will be called with.
:param current_retry_num: Current task retry. This will be 0 from new tasks and will be
incremented for each retry.
:param enqueued_time: Timestamp of when message was queued. If not provided then value set
from setting's timestamp function.
:param publisher_data: Str containing information about the publisher. If not provided the
value from settings used.
:param instantiate_task: Whether create instance of task_class. Default is false.
:param delete_func: Delete function from the SQS message.
"""
self._validate_task_payload(payload)
retry_count = current_retry_num or 0
self.id = sqs_message_id
self.sqs_queue_name = sqs_queue_name
self.sqs_receipt_handle = sqs_receipt_handle
# This represents the path to the task. The consumer will have a
# dictionary mapping these values to task classes.
if task_class is not None:
self.task_name = '.'.join([task_class.__module__, task_class.__name__])
else:
self.task_name = task_name
self.task_id = task_id
self.task_args = payload.get('args')
self.task_kwargs = payload.get('kwargs')
self.task_app_data = payload.get('app_data')
self.task_retry_num = retry_count
self._enqueued_time = enqueued_time or _get_current_timestamp()
self._publisher_data = publisher_data or _get_publisher_data()
# Lazily instantiate the task mapper.
if not self._task_mapper:
self._task_mapper = {k: utils.class_import_from_path(v)
for k, v in six.iteritems(settings.TASK_MAPPER)}
# This will instantiate the task.
if instantiate_task:
self.task_inst = self._class_from_path(self.task_name)(self._get_message_body())
self.delete_func = delete_func
