NestJs: Inject UserService in RolesGaurd

Issue

I have an UserService which is exported from user module like this:

@Module({
  imports: [
    MongooseModule.forFeature([{ name: User.name, schema: UserSchema }]),
    MongooseModule.forFeature([{ name: Profile.name, schema: ProfileSchema }]),
  ],
  controllers: [UserController],
  providers: [UserService],
  exports: [UserService],
})
export class UserModule {}

RolesGaurd

@Injectable()
export class RolesGuard implements CanActivate {
  constructor(
    private reflector: Reflector,
    @Inject(UserService) private readonly userService: UserService,
  ) {}

  canActivate(
    context: ExecutionContext,
  ): boolean | Promise<boolean> | Observable<boolean> {
    const roles = this.reflector.get(Roles, context.getHandler());
    if (!roles) {
      return true;
    }
    const request = context.switchToHttp().getRequest();
    const user = request.user;
    const params = request.params;

    if (!roles.includes(user.role)) {
      throw new UnauthorizedException(
        'You are not authorized to access this api endpoint',
      );
    }

    if (user.role === Role.ACCOUNT_MANAGER && params.organization) {
      // check if account manager is assigned a queried organization
      const isAssigned = this.userService.hasAccessToOrganization(
        user.userId,
        params.organization,
      );

      if (!isAssigned)
        throw new UnauthorizedException(
          'You are not authorized to perform action for this organization',
        );
    }

    return true;
  }
}

When I inject user service in roles gaurd I start to get this error for every module in which I am using RolesGaurd:

Error: Nest can't resolve dependencies of the RolesGuard (Reflector, ?). Please make sure that the argument UserService at index [1] is available in the CoachModule context.

Potential solutions:
- Is CoachModule a valid NestJS module?
- If UserService is a provider, is it part of the current CoachModule?
- If UserService is exported from a separate @Module, is that module imported within CoachModule?
  @Module({
    imports: [ /* the Module containing UserService */ ]
  })

What is the solution for this problem so that I won't need to add user service import to every module in which I am using RolesGaurd

Solution

you must have that provider available to all modules that is using the RolesGuard guard

So you should:

1. import a module that exports UserService, in every module that will use the guard, or
2. import a global module that exports UserService in the root module, or
3. register that provider in every module that will use the guard

Answered By - Micael Levi