support task-priorities when use RabbitMQ / Redis as broker

[b1ngz]

According to the official docs, celery support task-priorities when use RabbitMQ or Redis as broker, and in Advanced Options section, there is a priority option

• priority

  A number between 0 and 255, where 255 is the highest priority.

  Supported by: RabbitMQ, Redis (priority reversed, 0 is highest).

So i add priority field for model PeriodicTasks to support task-priorities.

[b1ngz]

And I saw Travis CI build failed due to line too long in the new migration file

/home/travis/build/celery/django-celery-beat/django_celery_beat/migrations/0006_periodictask_priority.py:10:80: E501 line too long (106 > 79 characters)

which code line is:

 ('django_celery_beat', '0005_add_solarschedule_events_choices_squashed_0009_merge_20181012_1416'),

The dependent squashed migration filename is too long. Any idea how to fix it?

[b1ngz]

Thanks. 😫 But ci still fail due to

/home/travis/build/celery/django-celery-beat/django_celery_beat/tzcrontab.py:73:21: W504 line break after binary operator
/home/travis/build/celery/django-celery-beat/django_celery_beat/tzcrontab.py:74:21: W504 line break after binary operator
...

These code is already in master, should i make some change to fix it?

[b1ngz]

Line break before a binary operator is more readable, but after modified, the CI still failed.

After google for this, I found the result of W503 and W504 are weird which cause CI failed, so i add them to the ignore list.