This document describes the current stable version of Celery (5.4). For development docs, go here.
celery.contrib.migrate
¶
Message migration tools (Broker <-> Broker).
- class celery.contrib.migrate.State[source]¶
Migration progress state.
- count = 0¶
- filtered = 0¶
- property strtotal¶
- total_apx = 0¶
- celery.contrib.migrate.migrate_task(producer, body_, message, queues=None)[source]¶
Migrate single task message.
- celery.contrib.migrate.migrate_tasks(source, dest, migrate=<function migrate_task>, app=None, queues=None, **kwargs)[source]¶
Migrate tasks from one broker to another.
- celery.contrib.migrate.move(predicate, connection=None, exchange=None, routing_key=None, source=None, app=None, callback=None, limit=None, transform=None, **kwargs)[source]¶
Find tasks by filtering them and move the tasks to a new queue.
- Parameters:
predicate (Callable) –
Filter function used to decide the messages to move. Must accept the standard signature of
(body, message)
used by Kombu consumer callbacks. If the predicate wants the message to be moved it must return either:a tuple of
(exchange, routing_key)
, ora
Queue
instance, or- any other true value means the specified
exchange
androuting_key
arguments will be used.
connection (kombu.Connection) – Custom connection to use.
source – List[Union[str, kombu.Queue]]: Optional list of source queues to use instead of the default (queues in
task_queues
). This list can also containQueue
instances.exchange (str, kombu.Exchange) – Default destination exchange.
routing_key (str) – Default destination routing key.
limit (int) – Limit number of messages to filter.
callback (Callable) – Callback called after message moved, with signature
(state, body, message)
.transform (Callable) – Optional function to transform the return value (destination) of the filter function.
Also supports the same keyword arguments as
start_filter()
.To demonstrate, the
move_task_by_id()
operation can be implemented like this:def is_wanted_task(body, message): if body['id'] == wanted_id: return Queue('foo', exchange=Exchange('foo'), routing_key='foo') move(is_wanted_task)
or with a transform:
def transform(value): if isinstance(value, str): return Queue(value, Exchange(value), value) return value move(is_wanted_task, transform=transform)
Note
The predicate may also return a tuple of
(exchange, routing_key)
to specify the destination to where the task should be moved, or aQueue
instance. Any other true value means that the task will be moved to the default exchange/routing_key.
- celery.contrib.migrate.move_by_idmap(map, **kwargs)[source]¶
Move tasks by matching from a
task_id: queue
mapping.Where
queue
is a queue to move the task to.Example
>>> move_by_idmap({ ... '5bee6e82-f4ac-468e-bd3d-13e8600250bc': Queue('name'), ... 'ada8652d-aef3-466b-abd2-becdaf1b82b3': Queue('name'), ... '3a2b140d-7db1-41ba-ac90-c36a0ef4ab1f': Queue('name')}, ... queues=['hipri'])
- celery.contrib.migrate.move_by_taskmap(map, **kwargs)[source]¶
Move tasks by matching from a
task_name: queue
mapping.queue
is the queue to move the task to.Example
>>> move_by_taskmap({ ... 'tasks.add': Queue('name'), ... 'tasks.mul': Queue('name'), ... })
- celery.contrib.migrate.move_direct(predicate, connection=None, exchange=None, routing_key=None, source=None, app=None, callback=None, limit=None, *, transform=<function worker_direct>, **kwargs)¶
Find tasks by filtering them and move the tasks to a new queue.
- Parameters:
predicate (Callable) –
Filter function used to decide the messages to move. Must accept the standard signature of
(body, message)
used by Kombu consumer callbacks. If the predicate wants the message to be moved it must return either:a tuple of
(exchange, routing_key)
, ora
Queue
instance, or- any other true value means the specified
exchange
androuting_key
arguments will be used.
connection (kombu.Connection) – Custom connection to use.
source – List[Union[str, kombu.Queue]]: Optional list of source queues to use instead of the default (queues in
task_queues
). This list can also containQueue
instances.exchange (str, kombu.Exchange) – Default destination exchange.
routing_key (str) – Default destination routing key.
limit (int) – Limit number of messages to filter.
callback (Callable) – Callback called after message moved, with signature
(state, body, message)
.transform (Callable) – Optional function to transform the return value (destination) of the filter function.
Also supports the same keyword arguments as
start_filter()
.To demonstrate, the
move_task_by_id()
operation can be implemented like this:def is_wanted_task(body, message): if body['id'] == wanted_id: return Queue('foo', exchange=Exchange('foo'), routing_key='foo') move(is_wanted_task)
or with a transform:
def transform(value): if isinstance(value, str): return Queue(value, Exchange(value), value) return value move(is_wanted_task, transform=transform)
Note
The predicate may also return a tuple of
(exchange, routing_key)
to specify the destination to where the task should be moved, or aQueue
instance. Any other true value means that the task will be moved to the default exchange/routing_key.
- celery.contrib.migrate.move_direct_by_id(task_id, dest, **kwargs)¶
Find a task by id and move it to another queue.
- celery.contrib.migrate.move_task_by_id(task_id, dest, **kwargs)[source]¶
Find a task by id and move it to another queue.
- celery.contrib.migrate.republish(producer, message, exchange=None, routing_key=None, remove_props=None)[source]¶
Republish message.
- celery.contrib.migrate.start_filter(app, conn, filter, limit=None, timeout=1.0, ack_messages=False, tasks=None, queues=None, callback=None, forever=False, on_declare_queue=None, consume_from=None, state=None, accept=None, **kwargs)[source]¶
Filter tasks.