I have a Post module which contains a controller, an entity class and two services - PostService and PostCacheService.
#Module({
controllers: [PostController],
providers: [PostService, PostCacheService, PaginationService, Logger],
imports: [
MikroOrmModule.forFeature({
entities: [Post, User, Comment],
})
],
exports: [PostService, PostCacheService],
})
export class PostModule {}
These are the classes I am injecting in PostService.
constructor(
#InjectRepository(Post)
private readonly postRepository: postRepository,
#InjectRepository(User)
private readonly userRepository: UserRepository,
#InjectRepository(Comment)
private readonly commentRepository: EntityRepository<Comment>,
private readonly logger: Logger,
private readonly postCacheService: PostCacheService,
) {}
And these are the classes I am injecting PostCacheService:
constructor(
#Inject(CACHE_MANAGER)
private cacheManager: Cache,
private logger: Logger,
private readonly postService: PostService,
) {}
I am injecting PostService in PostCacheService and injecting PostCacheService in PostService.
This is the error I am getting: Nest can't resolve dependencies of the PostCacheService (CACHE_MANAGER, Logger, ?). Please make sure that the argument dependency at index [2] is available in the PostModule context.
Any Idea how to fix this? And is it possible to use two services in a module?
Thanks.
Related
I have a bunch of services defined in my NestJS project. Some of the services are used as common services in a lot of other services. So they are imported in a few modules as well. But I noticed that when specific service srvD is imported in another service srvE2, the onModuleInit is not being called when the project starts.
The project starts without any error. Not really sure what's happening.
An example of the project structure. Issue is in srvE2
srvA.ts
#Injectable()
export class SrvA {
constructor(
private somePkgSrv: SomePkgSrv,
) {}
}
srvB.ts
#Injectable()
export class SrvB {
constructor(
private srvA: SrvA,
) {}
}
srvC.ts
#Injectable()
export class SrvC {
constructor(
private srvA: SrvA,
private srvB: SrvB,
) {}
}
srvD.ts
#Injectable()
export class SrvD {
constructor(
private srvA: SrvA,
private srvB: SrvB,
private srvC: SrvC,
) {}
}
srvD.module.ts
#Module({
providers: [SrvA, SrvB, SrvC, SrvD],
exports: [SrvD],
})
srvE1.ts
export class SrvE1 implements OnModuleInit {
constructor(
private srvA: SrvA,
private srvB: SrvB,
private srvC: SrvC,
) {}
async onModuleInit() {
console.log ('I can print! Yay!')
}
}
srvE2.ts
export class SrvE2 implements OnModuleInit {
constructor(
private srvA: SrvA,
private srvB: SrvB,
private srvC: SrvC,
private srvD: SrvD,
) {}
async onModuleInit() {
console.log ('I refuse to print so long as SrvD is here. Comment it and I will
print')
}
}
srvE.module.ts
#Module({
import: [SrvD], // the module
providers: [SrvE1, SrvE2], // the services
exports: [SrvE1, SrvE2],
})
I am dealing with a similar issue. Based on the comments here I tried changing the scoping for my new dependency from Scope.REQUEST to Scope.DEFAULT and that resolved my issue.
Request scoped providers spread this scope to whole chain of injection. Consequently, if you use it, even deeply inside your code, then onModuleInit won't run.
That being said, well ... request scope isn't very recommended, performance wise. Here is an interesting article : Why You Should Avoid Using Request-scoped Injection in NestJS
I've also bumped into this question & its answers : How to inject a request scoped provider at NestJS controller?
I've tried nj-request-scope package from #profes, and it works fine, especially to fix your problem.
If you don't want to use it, you can still try to move your onModuleInit code in a default scoped service.
I have service which use service form global module and parametr.
#Injectable()
export class UsersService {
_paramentr;
constructor(
parametr,
GlobalService,
) {
this._parametr = parametr;
}
}
How to inject UsersService to AnotherService with paramentr.
I know, I can do it by new UsersService, but inside UserService I can use anothore services, I must inject it from top level to deep into. It's not very convenient.
As the first example in NestJS shows(https://docs.nestjs.com/fundamentals/testing), the dependency for CatsController is CatsService, so they make new instance of CatService and pass it in the params for CatsController, As easy as pie.
In my real world usage the service is the main service of the system, it depends on a multiple services which they depend on other services and almost all of them including the main one depend on injecting repositories of TypeORM.
How should I handle such of a complex dependency injection when testing?
An example:
Class MainService {
constructor(
#InjectRepository(SomeEntity1)
private readonly someRepo1: Repository<SomeEntity1>,
#InjectRepository(SomeEntity2)
private readonly someRepo2: Repository<SomeEntity2>,
#InjectRepository(SomeEntity3)
private readonly someRepo2: Repository<SomeEntity3>,
private readonly someService1: SomeService1,
private readonly someService2: SomeService2,
private readonly someService3: SomeService3,
private readonly someService4: SomeService4,
private readonly someService5: SomeService5,
private readonly someService6: SomeService6,
private readonly someService7: SomeService7,
private readonly someService8: SomeService8,
private readonly someService9: SomeService9
){}
}
Class SomeService1 {
constructor(
#InjectRepository(SomeEntity1)
private readonly someRepo4: Repository<SomeEntity4>,
#InjectRepository(SomeEntity2)
private readonly someRepo5: Repository<SomeEntity5>,
#InjectRepository(SomeEntity3)
private readonly someRepo6: Repository<SomeEntity6>,
private readonly someService4: SomeService4,
private readonly someService5: SomeService10,
private readonly someService9: SomeService11
){}
}
I could find a solution online.
Thanks!
Generally when you do unit testing, you want to mock the dependencies, because you want to isolate the unit under test from the rest of your application.
Nest offer multiple ways to mock and Jest himself also offers other possibilities (https://jestjs.io/docs/es6-class-mocks).
One way is to use custom providers and provide your own mock:
const module = await Test.createTestingModule({
providers: [
MainService,
{
provide: SomeService1
useValue: MockSomeService1
}
]
})
.compile()
MockSomeService1 can be an object, a class or a factory function. Refers to the documentation for more details: https://docs.nestjs.com/fundamentals/custom-providers
If you have a lot of dependencies, that could be a good use case for using auto mocking and https://www.npmjs.com/package/#golevelup/ts-jest combined.
import { createMock } from '#golevelup/ts-jest'
const module = await Test.createTestingModule({
providers: [
MainService
]
})
.useMocker(() => createMock())
.compile()
More details on auto mocking: https://docs.nestjs.com/fundamentals/testing#auto-mocking
i'm pretty new in nestJS, so you can address me directly to documentation if my question was covered there, but i can't figure out how to create instance of none-injectable class.
Here is simplified version of code
export default class BoardingPass {
constructor(
orderId: string,
companyIATa: string,
token: string,
private readonly checkinOrder = new CheckinOrder(orderId, companyIATa, token) // <-- i need to instantiate CheckinOrder
) {}
}
So i need to instantiate the CheckinOrder class but it requires ApolloClient which can be provided only via nestJS DI mechanism
export default class CheckinOrder implements ICheckinOrder {
private order: CheckinOrderObject;
constructor(
private readonly id: string,
private readonly carrierIATACode: string,
private readonly accessToken: string,
private readonly apolloClient: ApolloClient<NormalizedCacheObject> // can't figure out how to pass it via DI
) {}
}
update
Read about custom providers, it seems like it what i need, but as you can see there is some dynamic arguments passed to init method of CheckinOrder
const checkinOrderProvider: Provider<CheckinOrder> = {
useFactory: apolloClient => new CheckinOrder('1', '2', '3', apolloClient),
provide: CheckinOrder,
inject: [ApolloClient]
};
#Module({
imports: [ConfigModule.forRoot(), ApolloClientModule],
providers: [checkinOrderProvider],
exports: [checkinOrderProvider]
})
export class GooglePayModule {}
and only Apollo client is static, so its still unclear how to implement regular interface composition when class Boarding pass has instance of class CheckinOrder as property :(
You can provide the factory method and use it somewhere to create your service just in time. As we do here:
https://github.com/valueadd-poland/pimp-my-pr/blob/master/libs/server/repository/infrastructure/src/lib/repositories/repository-repository.adapter.ts#L18
I'm using nestjs-i18n version 8.0.2 on my NestJS project to internationalize the strings.
I have a class in one of my modules that has this constructor:
constructor(
#InjectRepository(UsersRepository)
private readonly usersRepository: UsersRepository,
private readonly apiService: ApiService,
private readonly i18n: I18nRequestScopeService,
) {
}
This is the full class:
#QueryHandler(MyQuery)
export class MyQueryHandler implements IQueryHandler<MyQuery> {
constructor(
#InjectRepository(UsersRepository)
private readonly usersRepository: UsersRepository,
private readonly apiService: ApiService,
private readonly i18n: I18nRequestScopeService,
) {
}
async execute(query: MyQuery): Promise<MyResult> {
...
}
}
QueryHandler is a decorator from the cqrs library #nestjs/cqrs version 6.1.0, if this can be of any help.
For some reason, my 3 dependencies are undefined if I try to inject I18nRequestScopeService as shown, but usersRepository and apiService are correctly defined if I remove the I18nRequestScopeService injection.
No warnings or errors are shown on the log.
I have a custom ExceptionFilter with this constructor:
constructor(private readonly i18n: I18nRequestScopeService) {
}
and it works just fine.
In app.module.ts I have this:
#Module({
imports: [
...
I18nModule.forRoot({
fallbackLanguage: 'en',
parser: I18nJsonParser,
parserOptions: {
path: path.join(__dirname, 'i18n/'),
},
resolvers: [
{ use: QueryResolver, options: ['lang', 'locale', 'l'] },
new HeaderResolver(['x-custom-lang']),
AcceptLanguageResolver,
new CookieResolver(['lang', 'locale', 'l']),
],
})
],
...
})
I tried googling for the problem, but I had no luck. What am I missing?
Nest's implementation of CQRS does not allow for scoped providers. There is an open issue about it here