db_migrate.py

#!flask/bin/python
import imp

from migrate.versioning import api
from app import db
from config import SQLALCHEMY_DATABASE_URI
from config import SQLALCHEMY_MIGRATE_REPO
from pprint import pprint

migration = SQLALCHEMY_MIGRATE_REPO + '/versions/%03d_migration.py' % (api.db_version(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO) + 1)

tmp_module = imp.new_module('old_model')
old_model = api.create_model(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO)

exec old_model in tmp_module.__dict__

print "URI:       " + SQLALCHEMY_DATABASE_URI
print "REPO:      " + SQLALCHEMY_MIGRATE_REPO
pprint( old_model )
print "-----------------------"
pprint( tmp_module.meta )
print "-----------------------"
pprint( db )
print "-----------------------"
pprint( db.metadata )
print "-----------------------"

script = api.make_update_script_for_model(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO, tmp_module.meta, db.metadata)

open(migration, "wt").write(script)
api.upgrade(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO)

print 'New migration saved as ' + migration
print 'Current database version: ' + str(api.db_version(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO))