This package implements an Alembic hook that causes alembic revision --autogenerate to output PostgreSQL ALTER TYPE .. ADD VALUE SQL
statements as part of new migrations.
Add the line:
import alembic_autogenerate_enums
To the top of your env.py.
Generated migrations only work in one direction, since without a superuser account and a bunch of dangerous operations it isn't possible to remove PostgreSQL ENUM values. Despite that, the generated migrations contain downgrade code, just in case the implementation is improved (or e.g. extended to work with other DBs) at some later date.
Since ALTER TYPE .. ADD VALUE cannot run transactionally, each
op.sync_enum_values() call creates its own temporary private DB connection.
See https://bitbucket.org/zzzeek/alembic/issues/123/a-way-to-run-non-transactional-ddl