Question

我想在当前任务完成后每隔30分钟偶尔调用一次celery任务，但是有时任务花费的时间比预期的长，因为任务是从远程服务器下载文件。所以我不想使用celeryBeat。另外，使用自我。重试仅适用于我想是发生错误的时间。这是我的任务：

@shared_task(name="download_big", bind=True, acks_late=true, autoretry_for=(Exception, requests.exceptiosn.RequestException), retry_kwargs={"max_retries": 4, "countdown": 3}):
def download_big(self):
    my_file = session.get('example.com/hello.mp4')
    if my_file.status_code == requests.codes["OK"]:
        open("hello.mp4", "wb").write(my_file.content)
    else:
        self.retry()

更新：

好吧，我将结构更改为：

@shared_task(name="download_big", bind=True, acks_late=true, autoretry_for=(Exception, requests.exceptiosn.RequestException), retry_kwargs={"max_retries": 4, "countdown": 3}):
def download_big(url):
    my_file = session.get(url, name)
    if my_file.status_code == requests.codes["OK"]:
        open(name, "wb").write(my_file.content)
    else:
        self.retry()

@shared_task(name="download_all", bind=True, acks_late=true, autoretry_for=(Exception, requests.exceptiosn.RequestException), retry_kwargs={"max_retries": 4, "countdown": 3}):
def download_all(self):
    my_list = [...]  # bunch of urls with names
    jobs = []
    for name, url in my_list:
        jobs.append(download_big.si(url, name))
    group(jobs)()

因此，在这种情况下，我必须调用download_all方法而不是download_big，这样我可以并行下载文件，并且当所有小组任务完成后，都需要在30分钟后再次调用自身。

Answer 1

您可以尝试使用chord来运行一组任务，当它们完成时，将运行一个可用于重新计划的回调。

例如

from celery import chord

@shared_task(name="download_big", bind=True, acks_late=true, autoretry_for=(Exception, requests.exceptiosn.RequestException), retry_kwargs={"max_retries": 4, "countdown": 3}):
def download_big(url):
    my_file = session.get(url, name)
    if my_file.status_code == requests.codes["OK"]:
        open(name, "wb").write(my_file.content)
    else:
        self.retry()

@shared_task(name="download_all", bind=True, acks_late=true, autoretry_for=(Exception, requests.exceptiosn.RequestException), retry_kwargs={"max_retries": 4, "countdown": 3}):
def download_all(self):
    my_list = [...]  # bunch of urls with names
    jobs = []
    for name, url in my_list:
        jobs.append(download_big.si(url, name))

    # Run the group and reschedule once all tasks complete
    chord(jobs)(download_all.apply_async(countdown=1800))

任务成功执行后，芹菜任务自动调用而没有celerybeat

1 个答案: