django-migrate-project
Django management commands for project-wide (editable) migrations.
Overview
The django-migrate-project app aims to add management commands to make running full project migrations more sane and controllable. The concept is pretty simple: first collect any unapplied migrations into per-app migration files, then review and modify as need be, and finally apply the migrations.
By staging and consolidating unapplied migrations in a way that they can be edited and reviewed before applying, more confidence is gained that a rogue migration won't damage production tables. The collected and consolidated migrations are listed as replacements for the individual app migrations they represent so once they have been applied everything is in the same state as if the individual app migrations has been applied via 'migrate'.
Requirements
Requires Django 1.7+ and as such Python 2.7+ as well
Installation
Simply use pip to install:
$ pip install django-migrate-project
To be of any use django-migrate-project
must be added to the Django project
via INSTALLED_APPS
in the project settings.py
file:
INSTALLED_APPS = ( ... 'django_migrate_project', ... )
Usage
Two new management commands provide the core functionality. To gather up any unapplied migrations for the project simply run:
$ python manage.py collectmigrations
The default collection location is BASE_DIR/pending_migrations
. If the project's
settings.py
does not have a BASE_DIR
then a directory path must be provided
using the --output-dir
option.
The collected migrations are grouped per-app and have the filename format of
<app_label>_project.py
. These files can be edited to taste in order to
change the migration, the only important bit is to keep the replaces and
dependencies
fields in the migration the same, as those allow the bookkeeping
to be kept accurate.
Collected migrations are applied via:
$ python manage.py applymigrations
The default directory path is used again if possible, otherwise the path must
be provided via the --input-dir
option.
Finally, migrations can be unapplied easily as well, returning the migration state to what it was before by running:
$ python manage.py applymigrations --unapply
Experimental
Starting with v0.2.0 there's also the capability to generate project-level migrations as a way to capture monkey-patched models and other changes that shouldn't create migrations in a third-party app.
To use this functionality, first create a top-level migrations directory with a __init__.py file to make it a Python package. Then run the following command to create any new project-level migrations (changes not present in third-party app migrations):
$ python manage.py makeprojectmigrations
Assuming there are any migrations to generate, the top-level migrations directory should now be populated and you can migrate the project using:
$ python manage.py migrateproject
As with the applymigrations command, migrateproject also has an easy unapply functionality:
$ python manage.py migrateproject --unapply
While this functionality is well covered by tests it will remain 'experimental' until it gets a bit more real world use.
Contributing
Contributions are welcome, just create a pull request or issue on the GitHub repository for the project.