command.upgrade(alembic_cfg, "head") never returns and blocks the process indefinitely.

[oefterdal]

Bug Description:
Running command.upgrade(alembic_cfg, "head") never returns and blocks the process indefinitely.

Expected Behavior:
The process should complete and return, either successfully or with a failure.

To Reproduce:

def run_migrations():
    try:
        logger.info("Starting database migrations")
        alembic_cfg = Config("alembic.ini")
        command.upgrade(alembic_cfg, "head")
        logger.info("Database migrations completed successfully")
    except Exception as e:
        logger.error(f"Migration failed: {e}")
        raise

Error:

# Copy error here. Please include the full stack trace.

Environment:

• OS: macOS 14.15
• Python: 3.12
• Alembic: 1.13.1
• SQLAlchemy: 2.0.30
• Database: SQLite
• DBAPI: SQLModel 2.0.0

Additional Context:
The following workaround using subprocess works:

def run_migrations():
    try:
        logger.info("Starting database migrations")

        # Run the Alembic upgrade command using subprocess
        result = subprocess.run(["alembic", "upgrade", "head"], capture_output=True, text=True)
        if result.returncode != 0:
            logger.error(f"Alembic upgrade failed: {result.stderr}")
            raise RuntimeError(f"Alembic upgrade failed: {result.stderr}")
        
        logger.info("Database migrations completed successfully")
    except Exception as e:
        logger.error(f"Migration failed: {e}")
        raise
    finally:
        # Ensure the engine is disposed
        engine.dispose()
        logger.info("Disposed of the engine to close all connections.")

Have a nice day!