Multi-Repo Transactions¶

Use RepositoriesContainer when you need a single atomic transaction spanning multiple repositories.

Creating a container¶

from metaorm import RepositoriesContainer, RepositorySettings

settings = RepositorySettings(dsn="sqlite+aiosqlite:///:memory:")
container = RepositoriesContainer(settings=settings)

Getting repositories¶

user_repo = container.get_repository(UserRepository)
order_repo = container.get_repository(OrderRepository)

Atomic transaction across repositories¶

async with container.transaction():
    user = await user_repo.create_item(UserTable(name="Alice"))
    await order_repo.create_item(OrderTable(user_id=user.id, total=100))

container.transaction() stores the session in a contextvars.ContextVar. All repository operations within the async with block automatically reuse that session. Nested transaction() calls yield the same session.

Creating tables via container¶

You can also create tables for multiple repositories at once:

await container.create_tables(UserRepository, OrderRepository)

Nested transactions (savepoints)¶

For partial rollback inside a shared transaction use container.nested_transaction() (or repository.nested_transaction()). It creates a SQLAlchemy savepoint: an error inside the block rolls back only the savepoint, leaving the outer transaction open for further operations or commit.

async with container.transaction():
    user = await user_repo.create_item(UserTable(name="Bob"))
    try:
        async with container.nested_transaction():
            await order_repo.create_item(OrderTable(user_id=user.id, total=999.99))
            raise ValueError("Rollback nested order")
    except ValueError:
        pass
    # Bob stays, the order is rolled back