README

Micro-module saga extension library. Provides abstract saga base class, DBAL saga repository, and command dispatching infrastructure following the Dependency Inversion Principle.

Installation

composer require micro-module/saga

Dispatcher Interfaces

SagaCommandDispatcherInterface

Abstraction for dispatching commands from within sagas. Two implementations are provided:

• SyncSagaCommandDispatcher — dispatches synchronously via Tactician CommandBus
• OutboxSagaCommandDispatcher — enqueues asynchronously via SagaCommandQueueInterface

SagaCommandQueueInterface

Abstract queue contract. The saga package does NOT depend on outbox-bundle or any concrete queue implementation. The outbox package (or any other package) implements this interface and is wired via DI.

Dependency Inversion Diagram

                    saga package
                 ┌───────────────────────────────────────────────┐
                 │                                               │
                 │  SagaCommandDispatcherInterface               │
                 │          ▲              ▲                     │
                 │          │              │                     │
                 │  OutboxSaga-    SyncSaga-                     │
                 │  CommandDispatcher   CommandDispatcher        │
                 │          │              │                     │
                 │  SagaCommandQueueInterface   CommandBus       │
                 │          │              │                     │
                 └──────────┼──────────────┼─────────────────────┘
                            │              │
                 ┌──────────┼──────────────┼─────────────────────┐
                 │          │              │  outbox-bundle /     │
                 │  OutboxAwareTaskProducer    tactician-bundle   │
                 │  implements SagaCommandQueueInterface          │
                 └───────────────────────────────────────────────┘

Key rule: The arrow from OutboxAwareTaskProducer points TO the saga package interface — the saga package has zero dependency on the outbox package. This is the Dependency Inversion Principle in action.

Usage

Sync dispatch (Tactician)

// DI wiring
$dispatcher = new SyncSagaCommandDispatcher($commandBus);
$dispatcher->dispatch(new CreateNewsCommand($id));

Async dispatch via outbox (DIP)

// The queue implementation (OutboxAwareTaskProducer) lives in outbox-bundle
// and implements SagaCommandQueueInterface.
// Wire via DI alias — never hard-code the concrete class in your saga.

$dispatcher = new OutboxSagaCommandDispatcher($queue); // $queue is SagaCommandQueueInterface
$dispatcher->dispatch(new PublishNewsCommand($id));    // command must implement Serializable

Requirements

• PHP 8.0+
• league/tactician ^1.0
• micro-module/broadway ^2.6 (provides Broadway\Serializer\Serializable)