Django Migration Snapshots

Capture snapshots of your django project's migration history. These snapshots are represented as a directed graph using pygraphviz in both textual and graphical formats.

Documentation

The full documentation is at https://django-migration-snapshots.readthedocs.io.

Quickstart

Install Django Migration Snapshots:

pip install django-migration-snapshots

Add it to your INSTALLED_APPS:

INSTALLED_APPS = (
    ...
    "migration_snapshots",
    ...
)

1) Execute management command to create snapshot

# creates snapshot of entire migration history
python manage.py create_snapshot

# filter migrations before applied date (YYYY-MM-DD)
python manage.py create_snapshot --date="2022-10-15"

2) Create object programmatically or from the admin panel

MigrationSnapshot.objects.create(output_format="pdf")

3) Automatically create migration snapshots with the post_migrate signal

from django.apps import AppConfig
from django.db.models.signals import post_migrate

def my_snapshot_callback(sender, **kwargs):
    # Create migration snapshot
    MigrationSnapshot.objects.create(output_format="pdf")

class MyAppConfig(AppConfig):
    ...

    def ready(self):
        # send signal only once after all migrations execute
        post_migrate.connect(my_snapshot_callback, sender=self)

Text Snapshot

digraph {
    "admin/0001_initial" -> "auth/0001_initial"
    "admin/0001_initial" -> "contenttypes/0001_initial"
    "admin/0002_logentry_remove_auto_add" -> "admin/0001_initial"
    "admin/0003_logentry_add_action_flag_choices" -> "admin/0002_logentry_remove_auto_add"
    "auth/0001_initial" -> "contenttypes/0001_initial"
    "auth/0002_alter_permission_name_max_length" -> "auth/0001_initial"
    ...
}

Graphical Snapshot

Features

• MigrationSnapshot data model
• Supported output formats
  • BMP, CGIMAGE, DOT_CANON, DOT, GV, XDOT, XDOT12, XDOT14, EPS, EXR, FIG, GD, GIF, GTK, ICO, CMAP, ISMAP, IMAP, CMAPX, IMAGE_NP, CMAPX_NP, JPG, JPEG, JPE, JPEG_2000, JSON, JSON0, DOT_JSON, XDOT_JSON, PDF, PIC, PICT, APPLE_PICT, PLAIN_TEXT, PLAIN_EXT, PNG, POV_RAY, PS_PDF, PSD, SGI, SVG, SVGZ, TGA, TIF, TIFF, TK, VML, VMLZ, VRML, WBMP, WEBP, XLIB, X11
• View migration history based on the miigration's applied timestamp

TODO's

• Additional test coverage
• Setup tox
• Additional filters in management command (ie; per app, per model, etc.)

Local Development

make install
make test

Deployment

make build
make deploy

License

This project is provided under the BSD License.