django-migration-zero 2.4.1

Holistic implementation of 'migration zero' pattern for Django covering local changes and in-production database adjustments.

Welcome to django-migration-zero - the holistic implementation of "migration zero" pattern for Django covering local changes and CI/CD pipeline adjustments.

This package implements the "migration zero" pattern to clean up your local migrations and provides convenient management commands to recreate your migration files and updating your migration history on your environments (like test or production systems).

PyPI • GitHub • Full documentation

Creator & Maintainer: Beyonder Deutschland

Features

• Remove all existing local migration files and recreate them as initial migrations
• Configuration singleton in Django admin to prepare your clean-up deployment
• Management command for your pipeline to update Django's migration history table to reflect the changed migrations

Motivation

Working with any proper ORM will result in database changes which are reflected in migration files to update your different environment's database structure. These files are versioned in your repository and if you follow any of the most popular deployment approaches, they won't be needed when they are deployed on production. This means, they clutter your repo, might lead to merge conflicts in the future and will slow down your test setup.

Django's default way of handling this is called "squashing". This approach is covered broadly in the official documentation. The main drawback here is, that you have to take care of circular dependencies between models. Depending on your project's size, this can take a fair amount of time.

The main benefit of squashing migrations is, that the history stays intact, therefore it can be used for example in package which can be installed by anybody and you don't have control over their database.

If you are working on a "regular" application, you have full control over your data(bases) and once everything has been applied on the "last" system, typically production, the migrations are obsolete. To avoid spending much time on fixing squashed migrations you won't need, you can use the "migration zero" pattern. In a nutshell, this means:

• Delete all your local migration files
• Recreate initial migration files containing your current model state
• Fix the migration history on every of your environments

Installation

• Install the package via pip:

  pip install django-migration-zero

  or via pipenv:

  pipenv install django-migration-zero

• Add module to INSTALLED_APPS within the main django settings.py:

  INSTALLED_APPS = (
      ...
      'django_migration_zero',
  )
  

• Apply migrations by running:

  python ./manage.py migrate

• Add this block to your loggers in your main Django settings.py to show logs in your console.

LOGGING = {
    "handlers": {
        "console": {
            "class": "logging.StreamHandler",
        },
    },
    "loggers": {
        "django_migration_zero": {
            "handlers": ["console"],
            "level": "INFO",
            "propagate": True,
        },
    },
}

Releasing a new version

Releases are fully automated. Push a version tag and the pipeline will build, sign with Sigstore, publish to PyPI via Trusted Publishing, and create a GitHub Release — no API tokens needed.

git tag v<version>          # e.g. git tag v1.2.3
git push origin v<version>

Tags must start with v. Tags without the prefix won't trigger the pipeline.

First-time setup

Before the pipeline can run for the first time, an admin must:

1. Create GitHub Environment pypi

   • Go to Settings → Environments → New environment, name it exactly pypi
   • Under Deployment branches and tags, add a tag rule with pattern v*
   • Optionally add required reviewers for a manual approval gate

2. Configure PyPI Trusted Publisher

   • Go to PyPI → Project settings → Publishing → Add a new publisher
   • Fill in: Owner ambient-innovation, Repository django-migration-zero, Workflow release.yml, Environment pypi

Publish to ReadTheDocs.io

• Fetch the latest changes in GitHub mirror and push them
• Trigger new build at ReadTheDocs.io (follow instructions in admin panel at RTD) if the GitHub webhook is not yet set up.

Maintenance

Please note that this package supports the ambient-package-update. So you don't have to worry about the maintenance of this package. This updater is rendering all important configuration and setup files. It works similar to well-known updaters like pyupgrade or django-upgrade.

To run an update, refer to the documentation page of the "ambient-package-update".