nest-authify/src/guards/microservice-jwt-auth.guard.ts

Complete authentication and authorization package for NestJS - Monolith and Microservices ready with OAuth, JWT, Redis sessions

import { CanActivate, ExecutionContext, Injectable } from '@nestjs/common';
import { Reflector } from '@nestjs/core';
import { AuthMsClientService } from '../microservices/auth-ms-client.service';

@Injectable()
export class MicroserviceJwtAuthGuard implements CanActivate {
  constructor(
    private authMsClient: AuthMsClientService,
    private reflector: Reflector,
  ) { }

  async canActivate(context: ExecutionContext): Promise<boolean> {
    const isPublic = this.reflector.getAllAndOverride<boolean>('isPublic', [
      context.getHandler(),
      context.getClass(),
    ]);

    if (isPublic) {
      return true;
    }

    const request = context.switchToHttp().getRequest();
    const token = this.extractTokenFromHeader(request);

    if (!token) {
      return false;
    }

    try {
      const payload = await this.authMsClient.validateToken(token);
      if (payload.error) {
        return false;
      }
      request.user = payload;
      return true;
    } catch {
      return false;
    }
  }

  private extractTokenFromHeader(request: any): string | undefined {
    const [type, token] = request.headers.authorization?.split(' ') ?? [];
    return type === 'Bearer' ? token : undefined;
  }
}