How do you propagate a TypeORM transaction across multiple services in NestJS?

Q: How do you propagate a TypeORM transaction across multiple services in NestJS?

// Service A — orchestrates the transaction @Injectable() export class OrdersService { constructor( private dataSource: DataSource, private inventoryService: InventoryService, private notificationService: NotificationService, ) {} async placeOrder(dto: CreateOrderDto): Promise { return this.dataSource.transaction(async (manager: EntityManager) => { const order = manager.create(Order, dto); await manager.save(order); // Pass manager into child services — they share the same transaction await this.inventoryService.deductStock(dto.productId, dto.qty, manager); await this.notificationService.createNotification(order.id, manager); return order; }); } } // Service B — accepts optional manager for transaction participation @Injectable() export class InventoryService { constructor( @InjectRepository(Product) private readonly productRepo: Repository , ) {} async deductStock( productId: number, qty: number, manager?: EntityManager, ): Promise { const repo = manager ? manager.getRepository(Product) // transactional : this.productRepo; // standalone fallback await repo.decrement({ id: productId }, 'stock', qty); } } Pass EntityManager as an optional parameter — services remain callable both inside and outside a transaction. Never use the injected Repository inside a transaction — it operates on a separate connection. manager.getRepository(Entity) returns a repository bound to the transactional connection. This pattern avoids the need for cls-hooked (Continuation Local Storage) which adds runtime complexity. The orchestrating service owns the transaction boundary; child services are unaware of transaction details.

Difficulty: 5/10

transaction management, NestJS services, TypeORM

Pass the EntityManager from the transaction callback into each service method as an optional parameter. Child services use manager.getRepository(Entity) when the manager is provided, falling back to their injected repository for standalone calls. This keeps all writes in the same atomic unit without restructuring the service layer.

Transaction propagation via EntityManager parameter

Transaction propagation design rules:

1
Pass EntityManager as an optional parameter — services remain callable both inside and outside a transaction.

How do you propagate a TypeORM transaction across multiple services in NestJS?

Difficulty: 5/10

transaction management, NestJS services, TypeORM

Pass the EntityManager from the transaction callback into each service method as an optional parameter. Child services use manager.getRepository(Entity) when the manager is provided, falling back to their injected repository for standalone calls. This keeps all writes in the same atomic unit without restructuring the service layer.

Transaction propagation via EntityManager parameter

Transaction propagation design rules:

1
Pass EntityManager as an optional parameter — services remain callable both inside and outside a transaction.

How do you propagate a TypeORM transaction across multiple services in NestJS?

How do you propagate a TypeORM transaction across multiple services in NestJS?

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