What is the difference between moduleRef.get() and moduleRef.resolve() in NestJS?

Q: What is the difference between moduleRef.get() and moduleRef.resolve() in NestJS?

@Injectable() export class DynamicFactory { constructor(private moduleRef: ModuleRef) {} getSingleton() { // Synchronous — returns existing singleton instance return this.moduleRef.get(SingletonService, { strict: false }); } async getScoped() { // Async — creates a new context each call return await this.moduleRef.resolve(RequestScopedService); } async getScopedShared() { // Reuse contextId to share the same instance across multiple resolves const contextId = ContextIdFactory.create(); const svc1 = await this.moduleRef.resolve(ServiceA, contextId); const svc2 = await this.moduleRef.resolve(ServiceB, contextId); return { svc1, svc2 }; } } get() — synchronous, singletons only, returns the same cached instance. resolve() — asynchronous, works with DEFAULT/REQUEST/TRANSIENT scopes. resolve() creates a new DI sub-context — each call gives a fresh transient instance. Pass a shared contextId to resolve() to make multiple providers share the same scoped context.

Difficulty: 5/10

Dependency Injection, ModuleRef API, Lazy loading

moduleRef.get(token) retrieves a singleton from the module's provider map synchronously and cannot resolve scoped providers. moduleRef.resolve(token) creates a new DI context for REQUEST or TRANSIENT scoped providers — it is async and returns a new instance each call unless you reuse a contextId.

get() vs resolve()

Summary of differences:

1
get() — synchronous, singletons only, returns the same cached instance.
2
resolve() — asynchronous, works with DEFAULT/REQUEST/TRANSIENT scopes.
3

What is the difference between moduleRef.get() and moduleRef.resolve() in NestJS?

Difficulty: 5/10

Dependency Injection, ModuleRef API, Lazy loading

moduleRef.get(token) retrieves a singleton from the module's provider map synchronously and cannot resolve scoped providers. moduleRef.resolve(token) creates a new DI context for REQUEST or TRANSIENT scoped providers — it is async and returns a new instance each call unless you reuse a contextId.

get() vs resolve()

Summary of differences:

1
get() — synchronous, singletons only, returns the same cached instance.
2
resolve() — asynchronous, works with DEFAULT/REQUEST/TRANSIENT scopes.
3

What is the difference between moduleRef.get() and moduleRef.resolve() in NestJS?

moduleRef.get(token) retrieves a singleton from the module's provider map synchronously and cannot resolve scoped providers. moduleRef.resolve(token) creates a new DI context for REQUEST or TRANSIENT scoped providers — it is async and returns a new instance each call unless you reuse a contextId.

What is the difference between moduleRef.get() and moduleRef.resolve() in NestJS?

moduleRef.get(token) retrieves a singleton from the module's provider map synchronously and cannot resolve scoped providers. moduleRef.resolve(token) creates a new DI context for REQUEST or TRANSIENT scoped providers — it is async and returns a new instance each call unless you reuse a contextId.

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