我有这个Celery任务:
@app.task
def do_something(with_this):
# instantiate a class from a third party library
instance = SomeClass()
# this class uses callbacks to send progress info about
# the status and progress of what we're doing
def progress_callback(data):
# this status will change to 'finished' later
# but the return value that I want as the task result won't be returned
# so this is where I should mark the task as done manually
if data['status'] == 'working':
# I create a custom state for this task
do_something.update_state(
state = 'PROGRESS',
meta = data['progress']
)
# adding the callback to the instance
instance.add_callback(progress_callback)
# use the instance to do what I want
# this functions returns a value that I don't want as the task result
# so leaving this function without a return statement will make it None
instance.do_job(with_this)
如何将任务标记为手动完成?
在这种情况下,函数到达结尾而没有任何return
语句,因此我得到的task.result
是None
,我想将传递给回调函数的数据设置为结果,将任务标记为已完成。
我尝试使用:
app.backend.mark_as_done(do_something.request.id, data)
它成功设置了任务的状态和结果,但稍后将结果设置为函数的返回值None
。
答案 0 :(得分:10)
我终于找到了存储任务状态和结果的解决方案,然后通过引发Ignore
异常来忽略任务,例如:
from celery.exceptions import Ignore
@app.task
def do_something(with_this):
# store the state and result manually
# the SUCCESS state is set by this method
app.backend.mark_as_done(
do_something.request.id,
the_data_to_store
)
# we can also use update_state which calls
# backend.store_result just like mark_as_done
# but we have to set the state in this case
do_something.update_state(
state = celery.states.SUCCESS,
meta = the_data_to_store
)
# ignore the task so no other state is recorded
# like what was happening with my function in the question
# the task will still be acknowledged
raise Ignore()
如果您无法返回要存储的数据,这将非常有用。