title: How can I user configService in super()?
body: <p>I have a question about setting environmental variables.</p>
  <p>In official document, it says using ConfigModule in this case, but my case is a exception case.</p>
  <p>Because I would like to use it in super() in constructor.</p>
  <p>My code is the below.</p>
  <p>Is there any solution in this case?</p>
  <p>If you need more information, please let me know.</p>
  <p>Thank you all your support!!</p>
  <pre class="lang-js prettyprint-override"><code>// jwt.strategy.ts
  
  import { UnauthorizedException } from '@nestjs/common';
  import { ConfigService } from '@nestjs/config';
  import { PassportStrategy } from '@nestjs/passport';
  import { InjectRepository } from '@nestjs/typeorm';
  import { Strategy, ExtractJwt } from 'passport-jwt';
  import { JwtPayload } from './jwt-payload.interface';
  import { UserRepository } from './user.repository';
  export class JwtStrategy extends PassportStrategy(Strategy) {
      constructor(
          @InjectRepository(UserRepository)
          private userRepository: UserRepository,
          private configService: ConfigService,
      ) {
          super({
              jwtFromRequest: ExtractJwt.fromAuthHeaderAsBearerToken(),
              secretOrKey: configService.get('JWT_TOKEN'),
          });
      }
  
      async validate(payload: JwtPayload) {
          const { username } = payload;
          const user = await this.userRepository.findOne({ username });
  
          if (!user) {
              throw new UnauthorizedException();
          }
          return user;
      }
  }
  </code></pre>