Southmageddon - automatically nuke and recreate Django South migrations when deployed

delete_south_history.py

from django.core.management.base import BaseCommand
from south.models import MigrationHistory

class Command(BaseCommand):
    args = ''
    helps = 'Destroys South database migration history - DANGER, WILL ROBINSON'

    def handle(self, *args, **options):
        MigrationHistory.objects.all().delete()

has_old_migrations.py

from django.core.management.base import BaseCommand
from south.models import MigrationHistory
from django.conf import settings
from os.path import join, dirname, abspath, exists
import sys

class Command(BaseCommand):
    args = ''
    helps = 'Displays whether the South database has migrations not on disk'

    def handle(self, *args, **options):
        APPS = [..apps to check migrations for..]

        has_ghosts = False

        for m in MigrationHistory.objects.filter(app_name__in=APPS):
            fname = abspath(join(dirname(__file__), '..', '..', '..',
                '%s/migrations/%s.py' % (m.app_name, m.migration)))
            if not exists(fname):
                has_ghosts = True

        sys.exit(0 if has_ghosts else -1)

southmageddon.sh

#!/bin/bash

set -e

if python manage.py has_old_migrations; then
    echo "Old migrations detected, cleaning up ..."
    MYSELF=$(git log -n 1 '--pretty=format:%H' southmageddon.sh)
    HEAD=$(git rev-parse --abbrev-ref HEAD)
    if [ "$HEAD" = "HEAD" ]; then
        HEAD=$(git rev-list HEAD --max-count=1)
    fi
    LAST_OLD_MIGRATIONS=$(git cat-file commit $MYSELF | grep '^parent ' | cut -f2 -d' ')

    echo "Checking out $LAST_OLD_MIGRATIONS ..."
    git checkout -q $LAST_OLD_MIGRATIONS
    echo "Running latest migrations ..."
    python manage.py migrate
    echo "Checking out southmageddon code ($MYSELF) ..."
    git checkout -q $MYSELF
    echo "Running manage.py delete_south_history"
    python manage.py delete_south_history
    echo "Running fake initial migrations ..."
    python manage.py migrate --fake
    echo "Checking out current code ($HEAD) ..."
    git checkout $HEAD
    echo "Cleanup done."
fi