No changes detected in Alembic autogeneration of migrations with Flask-SQLAlchemy

Question

I\'m having trouble getting Alembic to autogenerate candidate migrations from changes to classes using db.Model (Flask-SQLAlchemy) instead of Base.

Answer 1

I also faced this issue and using this way to solve that:

open the migrations/env.py file, and on def run_migrations_online() function look at the context.configure, on Alembic 1.0.8 it should look like this:

with connectable.connect() as connection:
    context.configure(
        connection=connection,
        target_metadata=target_metadata,
        process_revision_directives=process_revision_directives,
        **current_app.extensions['migrate'].configure_args,
    )

Just remove or comment theprocess_revision_directives=process_revision_directives and then add the compare_type=True on that.

Like this:

with connectable.connect() as connection:
    context.configure(
        connection=connection,
        target_metadata=target_metadata,
        # process_revision_directives=process_revision_directives,
        **current_app.extensions['migrate'].configure_args,
        compare_type=True
    )