Factory Providers

Factory behavior in ClaDI is expressed through provider factories.

Why Factory Providers

Centralize construction logic for complex services.
Keep creation details out of domain/application layers.
Compose dependencies via typed tokens.
Apply lifecycle semantics (singleton, scoped, transient) consistently.

Basic Pattern

src/factory-provider.ts


container.register({
	provide: UserServiceToken,
	deps: [RepoToken, ClockToken],
	lifecycle: EDependencyLifecycle.SINGLETON,
	useFactory: (repo, clock) => new UserService(repo, clock),
});

Lifecycle-Aware Factory Pattern

src/factory-provider-lifecycle.ts


container.register({
	provide: PaymentGatewayToken,
	deps: [ConfigToken, LoggerToken],
	onInit: (gateway) => gateway.warmup?.(),
	afterResolve: (gateway) => gateway.markUsage?.(),
	onDispose: async (gateway) => {
		await gateway.close?.();
	},
	useFactory: (config, logger) => createGateway(config, logger),
});

Multi-Binding Factory Pattern

Use multi-binding when multiple implementations contribute to one contract:

src/factory-provider-multibinding.ts


container.register({
	provide: MiddlewareToken,
	isMultiBinding: true,
	useFactory: () => createAuthMiddleware(),
});
 
container.register({
	provide: MiddlewareToken,
	isMultiBinding: true,
	useFactory: () => createMetricsMiddleware(),
});
 
const middlewares = container.resolveAll(MiddlewareToken);