Using nestjs DI with class validator - nestjs

Question

Seems like a real pain in the brain...
There is a huge thread about this on github and other sites, many of them come down to using useContainer from the 'class-validator' but it does not work for me.
async function bootstrap() {
const app = await NestFactory.create(ApplicationModule);
useContainer(app, { fallback: true });
await app.listen(3000);
}
bootstrap();
Here's the injectable:
#ValidatorConstraint({ name: 'uniqueOnDatabase', async: true })
#Injectable()
export class UniqueOnDatabase implements ValidatorConstraintInterface {
constructor(
private readonly userService: UserService,
) {}
public async validate(val: any, args: ValidationArguments): Promise<boolean> {
const user = await this.userService.retrieveOneByEmail(val);
return !user;
}
public defaultMessage(args: ValidationArguments): string {
return `User with such an email address already exists in the DB`;
}
}
All I want to do is use my userService inside that UniqueOnDatabase class.
Here is the module where I am providing the UniqueOnDatabase:
import { Module, CacheModule } from '#nestjs/common';
import { ConfigModule } from '#nestjs/config';
import { CacheConfigService } from 'src/config/cache/config.service';
import { CacheService } from './services/cache.service';
import { CodeGenService } from './services/code-gen.service';
import { UserExistanceValidationPipe } from './pipes/user-existance.validation.pipe';
import { UsersModule } from 'src/users/users.module';
import { UniqueOnDatabase } from './validators/unique-on-database.validator';
#Module({
providers: [
CacheService,
CodeGenService,
UniqueOnDatabase,
],
imports: [
CacheModule.registerAsync({
imports: [ConfigModule],
useClass: CacheConfigService,
}),
UsersModule,
],
exports: [
CacheService,
CodeGenService,
UniqueOnDatabase,
],
})
export class SharedModule {}

Answer 1

Thanks #Albert for answering your question.
Adding #Albert's answer just in case someone misses the comments:
#JayMcDoniel Aaah, seems like I've figured out the solution. I should
have used useContainer(app.select(SharedModule), { fallbackOnErrors:
true }); instead of what I did at first...
Thanks again #Albert