Flask-Migrate integration

[dolfandringa]

I see a script db_migrate and db_upgrade in the bin folder, but no docs on how I am supposed to use it with flask appbuilder.
I see issue #373 about someone trying to integrate it themselves, and I can probably get that idea to work (I think the error there is he just doesn't import the model) but is there a way this is supposed to be integrated in flask appbuilder? Wouldn't it make sense to integrate it in fabmanager?

[dolfandringa]

I'd be happy to write some docs on it if I get some pointers.

[dolfandringa]

OK, I have it working now. I heavily borrowed ideas from superset. It would be great if fabmanager supports flask-migrate by default (contributions welcome?). I now wrote my own flask-script cli commands to implement it.

I made a script in app/bin/<appname> with the following:

#!/usr/bin/env python
# -*- coding: utf-8 -*-
import warnings
from flask.exthook import ExtDeprecationWarning
warnings.simplefilter('ignore', ExtDeprecationWarning)

from app.cli import manager

if __name__ == '__main__':
    manager.run()

And then in app/cli.py I implemented the command like this:

#!/usr/bin/env python
# -*- coding: utf-8 -*-

from flask_migrate import MigrateCommand
from flask_script import Manager

from app import app, db
from app.models import *

config = app.config


manager = Manager(app)
manager.add_command('db', MigrateCommand)

From there, you can start the flask-migrate stuff with app/bin/<appname> db init
After that you still need to change the target_metadata in app/migrate/env.py to point to the flask_appbuilder metadata.
At the top:

from flask_appbuilder import Base

Further down, change the existing target_metadata variable to:

target_metadata = Base.metadata

This will ensure it finds your flask_appbuilder sqlalchemy metadata. If you don't, it will actually create scripts to remove all flask_appbuilder tables, because it doesn't know about them.
Then (like always with flask-migrate) run app/bin/<appname> db migrate on an empty database to create your first migration script, which will create all tables like they are currently defined in your model, and then app/bin/<appname> db upgrade to actually run the migration.

[dpgaspar]

Hi @dolfandringa ,

New 0.11.0 solves this issue, made a small quickhowto with Flask-Migrate has an example: https://github.com/dpgaspar/Flask-AppBuilder/tree/master/examples/quickmigrate

[jabbawockeez]

Hi @dpgaspar I successfully ran the quickmigrate project but I have to detect the change of column type, so I add the compare_type=True as mentioned here, and then I ran it again but it stuck right before the upgrade, what is the problem here? Thanks.

[jabbawockeez]

Alright, since I use mysql as the store, I found out the problem. It's because that the type of the column "active" in the table ab_user is tinyint but is bool in model instead, so flask-migrate(alembic) detects the difference every time I try to upgrade, but as it's mentioned here, I think changing the column type to bool in mysql makes no sense, but I still don't know why it just stuck.
And one of the possible solutions is to ignore the table in detection