Flask Migrate using different postgres schemas ( __table_args__ = {'schema': 'test_schema']})

Question

I'm trying to use flask, sqlalchemy, and flask_migrate...

But every time run manage.py migrate, alembic always detect my model as a new table.

I think that i put table_args in my model to store table in a different postgres schema:

class Entry(db.Model):
    __table_args__ = {'schema': app.config['BASE_SCH']}
    id = db.Column(db.Integer, primary_key=True)
    title = db.Column(db.String(100))
    slug = db.Column(db.String(100), unique=True)
    body = db.Column(db.Text)
    status = db.Column(db.SmallInteger, default=STATUS_PUBLIC)
    created_timestamp = db.Column(db.DateTime, default=datetime.datetime.now)
    modified_timestamp = db.Column(db.DateTime, default=datetime.datetime.now, onupdate=datetime.datetime.now)

If I to delete the table_args line of my model, the flask migrate works properly. Storing my table in puclic postgres schema.

So, how can I use different postgres table schemas with flask?

Thanks!

Answer 1

Finally figured this out: there is an include_schemas option in configure that you have to set to True to force Alembic to scan all schemas before generating the migration.

(Slightly) more details: http://alembic.zzzcomputing.com/en/latest/api/runtime.html#alembic.runtime.environment.EnvironmentContext.configure.params.include_schemas

It's not completely clear to me why Alembic/Flask-Migrate was generating the migrations for tables in non default schemas without this option set in the first place... or rather, the fact that it would create migrations for non default schemas but not discover these tables in the DB is a surprising behavior.