Disable migrations when running unit tests in Django 1.7

Disable migrations when running unit tests in Django 1.7

Django 1.7 introduced database migrations.
When running the unit tests in Django 1.7, it forces a migrate, that takes a long time. So I would like to skip the django migrations, and create the database in the final state.
I know that ignoring the migrations can be a bad practice, as that part of the code would not be tested. But that's not the case: I'm running the full migrations in the CI test server (jenkins). I only want to skip the migrations in my local tests, where the speed matters.

Some context:
Until Django 1.6, when using South, I used the SOUTH_TESTS_MIGRATE setting:

By default, South’s syncdb command will also apply migrations if it’s run in non-interactive mode, which includes when you’re running tests - it will run every migration every time you run your tests.
If you want the test runner to use syncdb instead of migrate - for example, if your migrations are taking way too long to apply - simply set SOUTH_TESTS_MIGRATE = False in settings.py.

However, syncdb does not exist anymore, now it's migrate.
And from Django 1.8 I'll use the --keepdb parameter:

The --keepdb option can be used to preserve the test database between test runs. This has the advantage of skipping both the create and destroy actions which greatly decreases the time to run tests, especially those in a large test suite. If the test database does not exist, it will be created on the first run and then preserved for each subsequent run. Any unapplied migrations will also be applied to the test database before running the test suite.

So this question is limited to Django 1.7.

Solutions/Answers:

Answer 1:

Look at this workaround, posted by Bernie Sumption to the Django developers mailing list:

If makemigrations has not yet been run, the “migrate” command treats
an app as unmigrated, and creates tables directly from the models just
like syncdb did in 1.6. I defined a new settings module just for unit
tests called “settings_test.py”, which imports * from the main
settings module and adds this line:

MIGRATION_MODULES = {“myapp”: “myapp.migrations_not_used_in_tests”}

Then I run tests like this:

DJANGO_SETTINGS_MODULE=”myapp.settings_test” python manage.py test

This fools migrate into thinking that the app is unmigrated, and so
every time a test database is created it reflects the current
structure of models.py.

In Django 1.9, this situation is improved somewhat, and you can set the value to None:

MIGRATION_MODULES = {“myapp”: None}

Answer 2:

Here is the end of my settings file :

class DisableMigrations(object):

    def __contains__(self, item):
        return True

    def __getitem__(self, item):
        return None


TESTS_IN_PROGRESS = False
if 'test' in sys.argv[1:] or 'jenkins' in sys.argv[1:]:
    logging.disable(logging.CRITICAL)
    PASSWORD_HASHERS = (
        'django.contrib.auth.hashers.MD5PasswordHasher',
    )
    DEBUG = False
    TEMPLATE_DEBUG = False
    TESTS_IN_PROGRESS = True
    MIGRATION_MODULES = DisableMigrations()

based on this snippet

I disabled migrations only when tests are running

Answer 3:

django-test-without-migrations adds a --nomigrations flag to manage.py test. Works like a charm.

Answer 4:

Update: Never mind, this change was reverted before 1.10 final was released. Hopefully it will return in a future version.


Note that as of Django 1.10 this can be controlled by a test database setting.

MIGRATE

Default: True

If set to False, Django won’t use migrations to create the test database.

Answer 5:

https://gist.github.com/apollovy/22826f493ad2d06d9a9a22464730ce0b

MIGRATION_MODULES = {
    app[app.rfind('.') + 1:]: 'my_app.migrations_not_used_in_tests'
    for app in INSTALLED_APPS
}

Answer 6:

For django 1.9 and up the answer of Guillaume Vincent does not work anymore, so here’s a new solution:

I’m using this snippet in my settings file, after the definition of the INSTALLED_APPS

if os.environ.get('TESTS_WITHOUT_MIGRATIONS', False):
    MIGRATION_MODULES = {
        app.split('.')[-1]: None for app in INSTALLED_APPS
    }

It iterates over all installed apps and marks each as having no migration module. See the django docs for more information.

Using this snippet you can run your tests, setting the environment variable TESTS_WITHOUT_MIGRATIONS, e.g.:

TESTS_WITHOUT_MIGRATIONS=1 ./manage.py test

Answer 7:

I just figure out how to disable migrations after django 1.10,may be it could help for somebody. Here is link at git

class DisableMigrations(dict):
    def __contains__(self, item):
        return True

    def __getitem__(self, item):
        return None

DATABASES = DisableMigrations()

MIGRATION_MODULES = DisableMigrations()

Migrations for django 1.10 has two part,please look at load_disk and recorder

The part of load_disk for migrations model of app that be added at INSTALL_APP
And the part of recorder for database connection
For the version before 1.9 we need set MIGRATION_MODULES={'do.not.migrate':'notmigrations'} when you are running test
Now we need set it None like MIGRATION_MODULES={'do.not.migrate':None}
So if we do not want make migrations for any app, just extend a dict and return None for getitem function , and do the same at DATABASES, that is the right thing you need to do

PS: For command, you need to specify --setting=module.path.settings_test_snippet after test
PPS If you are working with pycharm ,do not set --settings options at Run/Debug configurations, just add path of settings_test_snippet.py at Custom setting. That just be fine!!

enjoy

References