gendesign/backend/alembic/env.py

"""Alembic env. Loads DB URL from app settings, registers all SQLAlchemy
models so autogenerate can detect schema drift."""

from logging.config import fileConfig

from sqlalchemy import engine_from_config, pool

# Import the models package so every ORM model registers on Base.metadata.
# Add new model modules in app/models/__init__.py as they appear.
import app.models  # noqa: F401
from alembic import context
from app.core.config import settings
from app.core.db import Base

config = context.config

# Inject runtime DB URL.
config.set_main_option("sqlalchemy.url", settings.database_url)

if config.config_file_name is not None:
    fileConfig(config.config_file_name)

target_metadata = Base.metadata


def run_migrations_offline() -> None:
    """Generate SQL without a live DB connection."""
    context.configure(
        url=config.get_main_option("sqlalchemy.url"),
        target_metadata=target_metadata,
        literal_binds=True,
        dialect_opts={"paramstyle": "named"},
        compare_type=True,
        compare_server_default=True,
    )
    with context.begin_transaction():
        context.run_migrations()


def run_migrations_online() -> None:
    """Run migrations against a live DB."""
    connectable = engine_from_config(
        config.get_section(config.config_ini_section, {}),
        prefix="sqlalchemy.",
        poolclass=pool.NullPool,
    )
    with connectable.connect() as connection:
        context.configure(
            connection=connection,
            target_metadata=target_metadata,
            compare_type=True,
            compare_server_default=True,
        )
        with context.begin_transaction():
            context.run_migrations()


if context.is_offline_mode():
    run_migrations_offline()
else:
    run_migrations_online()