Task Queue#
Tryton provides a way to run asynchronously some tasks. You must activate the worker in the queue section of the configuration and run the worker manager otherwise the tasks will be run at the end of the transaction.
A task is the parameters that defines how to call a method from a
Model
.
This include the context
, the
user
and the arguments.
The first argument of the method must be an instance or a list of instances of
Model
.
This other arguments must be JSON-ifiable.
A task is pushed into the Queue by calling the desired
method on the __queue__
.
This stores in the queue all the current parameters of the call and it will be
execute by a worker or at the end of the transaction if no worker is
configured.
The following context
keys are used as
parameters for the queue:
queue_name
The name of the queue. Default value is
default
.queue_scheduled_at
A
datetime.timedelta
to add to current time to define when the task should be started. Default value isNone
which means directly.queue_expected_at
A
datetime.timedelta
to add to current time to define when the task should be finished. Default value isNone
which means as soon as possible.queue_batch
An
integer
to divide the instances by batch of this size. If the value istrue
then the size is the value defined by the configurationqueue
ofbatch_size
. Default isNone
which means no division.
Warning
There is no access right verification during the execution of the task.
Example:
from trytond.model import Model
class MyModel(Model):
"My Model"
__name__ = 'my_model'
@classmethod
def launch(cls, records):
for record in records:
cls.__queue__.process(record, 42)
def process(self, value):
self.value = value