Mastering Flask Web Development - Second Edition

Creating a weekly digest

Say our blog has a lot of people who don't use RSS, and prefer mailing lists. We need some way to create a list of new posts at the end of every week to increase our site's traffic. To solve this problem, we will create a digest task that will be called by a beat worker at 10 am, every Saturday.

First, in blog/tasks.py, let's create our task as follows:

@celery.task(    bind=True,    ignore_result=True,    default_retry_delay=300,    max_retries=5)def digest(self):    # find the start and end of this week    year, week = datetime.datetime.now().isocalendar()[0:2]    date = datetime.date(year, 1, 1)    if (date.weekday() > 3):        date = date + datetime.timedelta(7 - date.weekday())    else:        date = date - datetime.timedelta(date.weekday()) delta ...