Upgrading Django

Jacob’s process

  1. Use virtualenv + pip
  2. Upgrade just Django. Don’t upgrade other things at the same time.
  3. Test and pray you have real unit tests.
  4. Upgrade 3rd Party Python Apps
  5. Deploy
  6. Start adding new features

Upgrade and Test

The process:

pip install -- upgrade Django
./manage.py test

This is why having unit tests is a good thing. But also click around and test things manually.

Things to watch for

  • Accessing internals: models._meta, queryset.query and other internals are not guaranteed by Django to not change.

    • So if your code depends on these things they can break between versions
    • Mark this code in comments as using internals
    • write tests against this code!
  • Arbitrary keyword arguments: model.save(), model.delete(), signal handlers, etc can change.

    • Use **kwargs instead of keyword arguments!
  • Monkeypatches

    • Just say no
  • Deprecated APIs and backwards incompatible changes (coming up next)

What about 3rd party apps?

  • The big ones should all work: South, Celery, Haystack, Tastypie, etc
  • Maybe make a sub-app or fork for those that do not.


Get requirements:

localhost$ pip freeze > requirements.txt
remote$ pip install -U -r requirements.txt

Safety path:

  1. Build new virtualenv
  2. Grab code
  3. Build reqs there
  4. Point apache at new version of site.