We Keep Coding

Error: Nest can't resolve dependencies of the CanModifyGuard (UsersService, ?)

just when I thought I do understand how the modules work and starting to play with guards which leads me to this error in full
Error: Nest can't resolve dependencies of the CanModifyGuard (UsersService, ?). Please make sure that the argument TelevisionsService at index [1] is available in the UsersModule context.
Potential solutions:
- If TelevisionsService is a provider, is it part of the current UsersModule?
- If TelevisionsService is exported from a separate #Module, is that module imported within UsersModule?
#Module({
imports: [ /* the Module containing TelevisionsService */ ]
})
CanModifyGuard was fine when the guard is using only TelevisionsService, once I added the UsersService and add the guard into the UsersController
The error above popped up.
Wonder if I can have another pair of eyes where I am setting this wrong?
app.module.ts
import { MiddlewareConsumer, Module } from '#nestjs/common';
import { AppController } from './app.controller';
import { AppService } from './app.service';
import { MongooseModule } from '#nestjs/mongoose';
import { ConfigModule } from '#nestjs/config';
import { UsersModule } from './resources/users/users.module';
import { AuthModule } from './resources/auth/auth.module';
import { CommonModule } from './resources/common/common.module';
import { TelevisionsModule } from './resources/televisions/televisions.module';
import { CurrentUserMiddleware } from './common/middlewares/current-user.middleware';
#Module({
imports: [
ConfigModule.forRoot(),
MongooseModule.forRoot(process.env.DATABASE_URL),
UsersModule,
AuthModule,
CommonModule,
TelevisionsModule,
],
controllers: [AppController],
providers: [AppService],
})
export class AppModule {
configure(consumer: MiddlewareConsumer) {
consumer.apply(CurrentUserMiddleware).forRoutes('*');
}
}
can-modify.guard.ts
import {
CanActivate,
ExecutionContext,
Injectable,
UnauthorizedException,
} from '#nestjs/common';
import { TelevisionsService } from '../../resources/televisions/televisions.service';
import { UsersService } from '../../resources/users/users.service';
#Injectable()
export class CanModifyGuard implements CanActivate {
constructor(
private readonly usersService: UsersService,
private readonly televisionsService: TelevisionsService,
) {}
async canActivate(context: ExecutionContext): Promise<boolean> {
//logics here
}
}
users.module.ts
import { Module } from '#nestjs/common';
import { UsersController } from './users.controller';
import { UsersService } from './users.service';
import { MongooseModule } from '#nestjs/mongoose';
import { User, UserSchema } from './user.entity';
#Module({
imports: [
MongooseModule.forFeature([{ name: User.name, schema: UserSchema }]),
],
exports: [UsersService],
controllers: [UsersController],
providers: [UsersService],
})
export class UsersModule {}
televisions.module.ts
import { Module } from '#nestjs/common';
import { TelevisionsController } from './televisions.controller';
import { TelevisionsService } from './televisions.service';
import { MongooseModule } from '#nestjs/mongoose';
import { Television, TelevisionSchema } from './television.entity';
import { UsersModule } from '../users/users.module';
#Module({
imports: [
MongooseModule.forFeature([
{ name: Television.name, schema: TelevisionSchema },
]),
UsersModule,
],
exports: [TelevisionsService],
controllers: [TelevisionsController],
providers: [TelevisionsService],
})
export class TelevisionsModule {}
auth.module.ts
import { Module } from '#nestjs/common';
import { AuthService } from './auth.service';
import { AuthController } from './auth.controller';
import { UsersModule } from '../users/users.module';
import { ConfigModule } from '#nestjs/config';
import authConfig from './config/auth.config';
#Module({
imports: [UsersModule, ConfigModule.forFeature(authConfig)],
controllers: [AuthController],
providers: [AuthService],
})
export class AuthModule {}
common.module.ts (dont think this file would have any effect but just in case)
import { Module } from '#nestjs/common';
import { APP_GUARD } from '#nestjs/core';
import { AuthorizationRolesGuard } from '../../common/guards/authorization-roles.guard';
#Module({
providers: [
{
provide: APP_GUARD,
useClass: AuthorizationRolesGuard,
},
],
})
export class CommonModule {}
In order to use the guard, I added the guard to the specific route #UseGuards(CanModifyGuard) and again, it is working fine when I added this guard into television controller but once I added it to user controller the error pops up.
As the error mentioned for potential solutions even though UsersModule is not using any of the TelevisionsService I still imported TelevisionsModule into UsersModule but no luck on getting this fix...and instead I would get another error and said potential cause A circular dependency between modules. Use forwardRef() to avoid it. I read the doc about it and also tried using forwardRef() but still didn't fix it. I might have put the forwardRef() in the wrong place because I am not sure where I should use it.
Thank you in advance for any suggestions or advices.

If I'm understanding your set up correctly, you have a circular dependency on the modules, so you need to forwardRef the imports for those. Using these modules should fix your issue:
user.module.ts
#Module({
imports: [
MongooseModule.forFeature([{ name: User.name, schema: UserSchema }]),
forwardRef(() => TelvisionsModule),
],
exports: [UsersService],
controllers: [UsersController],
providers: [UsersService],
})
export class UsersModule {}
televisons.module.ts
#Module({
imports: [
MongooseModule.forFeature([
{ name: Television.name, schema: TelevisionSchema },
]),
forwardRef(() => UsersModule),
],
exports: [TelevisionsService],
controllers: [TelevisionsController],
providers: [TelevisionsService],
})
export class TelevisionsModule {}

Nest can't resolve dependencies of the JwtService

I have created some modules here but i am facing an error
Auth module
import { Module } from "#nestjs/common";
import { AuthService } from "./auth.service";
import { LocalStrategy } from "./local.strategy";
import { JwtStrategy } from "./jwt.strategy";
import { UsersModule } from "../users/users.module";
import { PassportModule } from "#nestjs/passport";
import { JwtModule, JwtService } from "#nestjs/jwt";
import { jwtConstants } from "./constants";
import { ConfigModule, ConfigService } from "#nestjs/config";
#Module({
imports: [
UsersModule,
PassportModule,
JwtModule.register({
secret: jwtConstants.secret,
signOptions: { expiresIn: "1d" },
}),
],
providers: [AuthService, LocalStrategy, JwtStrategy],
exports: [AuthService, LocalStrategy, JwtStrategy],
})
export class AuthModule {}
Email module
import { Module } from "#nestjs/common";
import EmailService from "./email.service";
import { ConfigModule } from "#nestjs/config";
import { EmailConfirmationService } from "./emailConfirmation.service";
import { EmailConfirmationController } from "./emailConfirmation.controller";
import { EmailConfirmationGuard } from "./guards/emailConfirmation.guard";
import { AuthModule } from "src/auth/auth.module";
import { UsersModule } from "src/users/users.module";
#Module({
imports: [ConfigModule,AuthModule,UsersModule],
providers: [EmailService,EmailConfirmationService,EmailConfirmationGuard],
exports: [EmailConfirmationService,EmailConfirmationGuard],
controllers : [EmailConfirmationController]
})
export class EmailModule {}
User module
import { Module } from "#nestjs/common";
import { UsersService } from "./users.service";
import { UsersController } from "./users.controller";
import { MongooseModule } from "#nestjs/mongoose";
import { UserSchema } from "./entities/user.entity";
import { EmailModule } from "src/email/email.module";
#Module({
imports: [MongooseModule.forFeature([{ name: "User", schema: UserSchema }]),EmailModule],
providers: [UsersService],
exports: [UsersService],
controllers: [UsersController],
})
export class UsersModule {}
Error I am facing
[Nest] 9200 - 09/26/2021, 3:43:15 PM ERROR [ExceptionHandler] Nest cannot create the EmailModule instance.
The module at index [1] of the EmailModule "imports" array is undefined.
Potential causes:
- A circular dependency between modules. Use forwardRef() to avoid it. Read more: https://docs.nestjs.com/fundamentals/circular-dependency
- The module at index [1] is of type "undefined". Check your import statements and the type of the module.
Scope [AppModule -> AuthModule -> UsersModule]
Error: Nest cannot create the EmailModule instance.
The module at index [1] of the EmailModule "imports" array is undefined.
Potential causes:
- A circular dependency between modules. Use forwardRef() to avoid it. Read more: https://docs.nestjs.com/fundamentals/circular-dependency
- The module at index [1] is of type "undefined". Check your import statements and the type of the module.
What am i missing ?
EmailConfirmationService is used in UsersController
UserService is used in EmailConfirmationService

You have JwtService listed in your imports. Imports are for modules only.
Share the code from JwtService as well so that we can make sure there are no other issues.
Update:
If the EmailModule wants to use the exports from the AuthModule (JwtService in this case), it must add the AuthModule to its imports array.
This is the entire premise of the DI system, modules share things between eachother by placing the thing they intend to share in the exports array. After that, any module can add the Source module to its imports array to gain access to the things that the source exported. The error message literally spells it out for you:
If JwtService is exported from a separate #Module, is that module imported within EmailModule? #Module({ imports: [ /* the Module containing JwtService */ ] })

In order to use EmailService in you UserController and also UserService is used in EmailConfirmationService then you have to do something like this in UserModule:
imports: [forwardRef(() => EmailModule)]
and inside the EmailModule do the same thing for the UserModule:
imports: [forwardRef(() => UserModule)]
Rest of the imports should be without the forwardRef(()=>)
you can read more about circular dependency here https://docs.nestjs.com/fundamentals/circular-dependency

Make sure your target in tsconfig.json is es6.

Nest can't resolve dependencies of the UsersService (UserModel, ?)

my user.module.ts:
import { forwardRef, Module } from '#nestjs/common';
import { UsersService } from './users.service';
import { UsersController } from './users.controller';
import { UserSchema } from './schemas/user.schema';
import { MongooseModule } from '#nestjs/mongoose';
import { AuthModule } from 'src/auth/auth.module';
#Module({
imports: [MongooseModule.forFeature([{name: 'User', schema: UserSchema}]),AuthModule],
controllers: [UsersController],
providers: [UsersService],
exports: [UsersService]
})
export class UsersModule {}
my auth.module.ts
import { forwardRef, Module } from '#nestjs/common';
import { AuthService } from './auth.service';
import { UsersModule } from '../users/users.module';
import { PassportModule } from '#nestjs/passport';
import { LocalStrategy } from './local.strategy';
#Module({
imports: [forwardRef(() => UsersModule), PassportModule],
providers: [AuthService, LocalStrategy],
})
export class AuthModule {}
my app.module.ts
import { Module } from '#nestjs/common';
import { MongooseModule } from '#nestjs/mongoose';
import { AppController } from './app.controller';
import { AppService } from './app.service';
import { UsersModule } from './users/users.module';
#Module({
imports: [UsersModule,MongooseModule.forRoot('mongodb://localhost:27017/nest1')],
controllers: [AppController],
providers: [AppService],
})
export class AppModule {}
this are giving me error:
[12:55:42 pm] Found 0 errors. Watching for file changes.
[Nest] 15944 - 20/09/2021, 12:55:45 pm LOG [NestFactory] Starting
Nest application... [Nest] 15944 - 20/09/2021, 12:55:45 pm LOG
[InstanceLoader] MongooseModule dependencies initialized +126ms [Nest]
15944 - 20/09/2021, 12:55:46 pm ERROR [ExceptionHandler] Nest can't
resolve dependencies of the UsersService (UserModel, ?). Please make
sure that the argument AuthService at index [1] is available in the
UsersModule context.
Potential solutions:
If AuthService is a provider, is it part of the current UsersModule?
If AuthService is exported from a separate #Module, is that module imported within UsersModule? #Module({
imports: [ /* the Module containing AuthService */ ] })
Error: Nest can't resolve dependencies of the UsersService (UserModel,
?). Please make sure that the argument AuthService at index [1] is
available in the UsersModule context.
Potential solutions:
If AuthService is a provider, is it part of the current UsersModule?
If AuthService is exported from a separate #Module, is that module imported within UsersModule? #Module({
imports: [ /* the Module containing AuthService */ ] })
at Injector.lookupComponentInParentModules (C:\Users\Asus\Desktop\BILDEMP\ems-by-nestjs\employee-management-system\node_modules#nestjs\core\injector\injector.js:193:19)
at Injector.resolveComponentInstance (C:\Users\Asus\Desktop\BILDEMP\ems-by-nestjs\employee-management-system\node_modules#nestjs\core\injector\injector.js:149:33)
at resolveParam (C:\Users\Asus\Desktop\BILDEMP\ems-by-nestjs\employee-management-system\node_modules#nestjs\core\injector\injector.js:103:38)
at async Promise.all (index 1)
at Injector.resolveConstructorParams (C:\Users\Asus\Desktop\BILDEMP\ems-by-nestjs\employee-management-system\node_modules#nestjs\core\injector\injector.js:118:27)
at Injector.loadInstance (C:\Users\Asus\Desktop\BILDEMP\ems-by-nestjs\employee-management-system\node_modules#nestjs\core\injector\injector.js:47:9)
at Injector.loadProvider (C:\Users\Asus\Desktop\BILDEMP\ems-by-nestjs\employee-management-system\node_modules#nestjs\core\injector\injector.js:69:9)
at async Promise.all (index 3)
at InstanceLoader.createInstancesOfProviders (C:\Users\Asus\Desktop\BILDEMP\ems-by-nestjs\employee-management-system\node_modules#nestjs\core\injector\instance-loader.js:44:9)
at C:\Users\Asus\Desktop\BILDEMP\ems-by-nestjs\employee-management-system\node_modules#nestjs\core\injector\instance-loader.js:29:13

I'm going to make some assumptions about your service constructors, as you haven't provided those:
You have what looks to be a circular reference between the UserModule and the AuthModule. Because of this, in the imports of each module you need to use forwardRef of the module you're importing.
#Module({
imports: [forwardRef(() => UserModule), ...rest],
providers,
controllers,
exports
})
export class AuthModule {}
#Module({
imports: [forwardRef(() => AuthModule), ...rest],
providers,
controllers,
exports
})
export class UserModule {}
And speaking of exports above, you need to export a provider if you plan to use it outside of the module where it is in the providers (e.g. to use AuthService inside of UserService, the AuthModule needs to have providers: [AuthService] and exports: [AuthService]. This makes the provider available elsewhere.
Now, to make use of circular dependencies inside of the services, you also need to make use of forwardRef. In this case it will look like #Inject(forwardRef(() => OtherClass)) private readonly other: OtherClass, so you'd have something like
#Injectable()
export class UserService {
constructor(
#Inject(forwardRef(() => AuthService)) private readonly auth: AuthService,
private readonly dep2: DependencyClass2
) {}
// rest of values
}
You'll do the same thing in the AuthService but replacing AuthService in the #Inject() with UserService.

You need to import all the dependencies of UserService in UserModule. If you still can't figure out then please also add your user.service.ts file in the question.

You have to export the auth service in the authmodule in order to be able to inject it in the user service.

Nest can't resolve dependencies of the CommonModule

I'm new in NEST.js world, and I trying to create simple middleware.
First, I created a middleware with this command:
nest g middleware common/middleware/logging
And after I add my code
import { Injectable, NestMiddleware } from '#nestjs/common';
#Injectable()
export class LoggingMiddleware implements NestMiddleware {
use(req: any, res: any, next: () => void) {
console.time('Request-response time');
console.log('Hi from middleware!');
res.on('finish', () => console.timeEnd('Request-response time'));
next();
}
}
And finally, I add the middleware
import { Module, MiddlewareConsumer } from '#nestjs/common';
import { APP_GUARD } from '#nestjs/core';
import { ApiKeyGuard } from './guards/api-key.guard';
import { ConfigModule } from '#nestjs/config';
import { LoggingMiddleware } from './middleware/logging.middleware';
#Module({
imports: [
ConfigModule
],
providers: [
{
provide: APP_GUARD,
useClass: ApiKeyGuard
}
]
})
export class CommonModule {
constructor(consumer: MiddlewareConsumer) {
consumer.apply(LoggingMiddleware).forRoutes('*')
}
}
But when i try to run it:
Nest can't resolve dependencies of the CommonModule (?). Please make
sure that the argument Object at index [0] is available in the
CommonModule context.
Potential solutions:
If Object is a provider, is it part of the current CommonModule?
If Object is exported from a separate #Module, is that module imported within CommonModule? #Module({
imports: [ /* the Module containing Object */ ] }) +2ms Error: Nest can't resolve dependencies of the CommonModule (?). Please make
sure that the argument Object at index [0] is available in the
CommonModule context.
Potential solutions:
If Object is a provider, is it part of the current CommonModule?
If Object is exported from a separate #Module, is that module imported within CommonModule? #Module({
imports: [ /* the Module containing Object */ ] })
Can you help me?

The MiddlewareConsumer isn't a part of the constructor. Rather, your module class should implement NestModule and should have a configure method that takes in the consumer: MiddlewareConsumer as the first and only paramter.
#Module({
imports: [
ConfigModule
],
providers: [
{
provide: APP_GUARD,
useClass: ApiKeyGuard
}
]
})
export class CommonModule implmenets NestModule {
configure(consumer: MidlewareConsumer) {
consumer.apply(LoggingMiddleware).forRoutes('*')
}
}

Nest can't resolve dependencies of custom service

I am basically follow this tutorial with very minor modifications:link
I am using nest 6.14.2 on node 12.10.0.
When running my app I get:
> recon-backend#0.0.1 start C:\Users\e5553079\Desktop\Node_Projects\recon-backend
> nest start
[Nest] 8324 - 02/10/2020, 9:28:21 AM [NestFactory] Starting Nest application...
[Nest] 8324 - 02/10/2020, 9:28:21 AM [InstanceLoader] MongooseModule dependencies initialized +53ms
[Nest] 8324 - 02/10/2020, 9:28:21 AM [ExceptionHandler] Nest can't resolve dependencies of the ReconQueryService (?). Please make sure that the argument ReconQueryModel at index [0] is available in the AppModule context.
Potential solutions:
- If ReconQueryModel is a provider, is it part of the current AppModule?
- If ReconQueryModel is exported from a separate #Module, is that module imported within AppModule?
#Module({
imports: [ /* the Module containing ReconQueryModel */ ]
})
+2ms
Error: Nest can't resolve dependencies of the ReconQueryService (?). Please make sure that the argument ReconQueryModel at index [0] is available in the AppModule context.
My files look like this:
1. app.module.ts
import { Module } from '#nestjs/common';
import { AppController } from './app.controller';
import { AppService } from './app.service';
import { MongooseModule } from '#nestjs/mongoose';
import { ReconQueryModule } from './reconQuery/reconQuery.module';
import { ReconQueryService } from './reconQuery/reconQuery.service';
import { ReconQueryController } from './reconQuery/reconQuery.controller';
#Module({
imports: [
MongooseModule.forRoot('mongodb://localhost/backend-app', { useNewUrlParser: true }),
ReconQueryModule
],
controllers: [AppController, ReconQueryController],
providers: [AppService, ReconQueryService],
})
export class AppModule {}
2. reconQuery.service.ts
import { Injectable } from '#nestjs/common';
import { Model } from 'mongoose';
import { InjectModel } from '#nestjs/mongoose';
import { ReconQuery } from './interfaces/reconQuery.interface';
import { CreateReconQueryDTO } from './dto/create-reconQuery.dto';
#Injectable()
export class ReconQueryService {
constructor(#InjectModel('ReconQuery') private readonly reconQueryModel: Model<ReconQuery>) { }
// Fetch all queries
async getAllQueries(): Promise<ReconQuery[]> {
const queries = await this.reconQueryModel.find().exec();
return queries;
}
...
3. reconQuery.interface.ts
import { Document } from 'mongoose';
export interface ReconQuery extends Document {
readonly id: number;
readonly name: string;
readonly sql: string;
}
4. reconQuery.module.ts
import { Module } from '#nestjs/common';
import { ReconQueryController } from './reconQuery.controller';
import { ReconQueryService } from './reconQuery.service';
import { MongooseModule } from '#nestjs/mongoose';
import { ReconQuerySchema } from './schemas/reconQuery.schema';
#Module({
imports: [
MongooseModule.forFeature([{ name: 'ReconQuery', schema: ReconQuerySchema }])
],
controllers: [ReconQueryController],
providers: [ReconQueryService]
})
export class ReconQueryModule {}
I wonder why it cries about ReconQueryModel as I do not have such an entity, just a ReconQuery interface.

You have extra ReconQueryService provided in AppModule.
import { Module } from '#nestjs/common';
import { AppController } from './app.controller';
import { AppService } from './app.service';
import { MongooseModule } from '#nestjs/mongoose';
import { ReconQueryModule } from './reconQuery/reconQuery.module';
import { ReconQueryService } from './reconQuery/reconQuery.service';
import { ReconQueryController } from './reconQuery/reconQuery.controller';
#Module({
imports: [
MongooseModule.forRoot('mongodb://localhost/backend-app', { useNewUrlParser: true }),
ReconQueryModule
],
controllers: [AppController, ReconQueryController],
providers: [AppService, ReconQueryService], // <-- this causes the error
})
export class AppModule {}
#InjectModel() is provided by calling MongooseModule.forFeature(...) on a certain #Module(). ReconQueryService in ReconQueryModule is fine because that's where you have MongooseModule.forFeature() called so #InjectModel() is provided properly. However, in AppModule, you don't have MongooseModule.forFeature() so Nest cannot resolve the #InjectModel() for ReconQueryService.
Check if you really need to use ReconQueryService in AppModule (services and controllers declared in AppModule). If you don't, then remove ReconQueryService from providers array. If you do, then go to ReconQueryModule and do the following:
import { Module } from '#nestjs/common';
import { ReconQueryController } from './reconQuery.controller';
import { ReconQueryService } from './reconQuery.service';
import { MongooseModule } from '#nestjs/mongoose';
import { ReconQuerySchema } from './schemas/reconQuery.schema';
#Module({
imports: [
MongooseModule.forFeature([{ name: 'ReconQuery', schema: ReconQuerySchema }])
],
controllers: [ReconQueryController],
providers: [ReconQueryService],
exports: [ReconQueryService] // <-- add this line
})
export class ReconQueryModule {}
exported things will be available to use outside of the module they're provided in. Just import that module somewhere else.