Make Django Tests Always Rebuild the Database if It Exists
If you use Django’s test runner, you’ll probably have encountered this message:
$ python manage.py test Creating test database for alias 'default'... Got an error creating the test database: database "myproject_test" already exists Type 'yes' if you would like to try deleting the test database 'myproject_test', or 'no' to cancel:
The main reason this happens is that the last test run crashed and it left the database around. It can be annoying when you start the test run, go for a cup of tea, and come back to this prompt still waiting, rather than a complete test run.
Here’s how to make Django always rebuild the database in this case.
We’ll do it by extending
test with our own custom management command.
Create a new
test management command inside one of your Django apps, for example
testapp/management/commands/test.py. Then add this content:
from django.core.management.commands.test import Command as BaseCommand class Command(BaseCommand): def handle(self, *test_labels, **options): # Wrap Django's built-in test command to always delete the database if # it exists options["interactive"] = False return super().handle(*test_labels, **options)
This works by intercepting the normal
handle() method to first always set the
interactive option to
False. This is the same as always passing the
--noinput command line flag, the documented way of forcing a database rebuild.
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- Getting a Django Application to 100% Test Coverage
- Django’s Test Case Classes and a Three Times Speed-Up
- How to Add Database Modifications Beyond Migrations to Your Django Project