AuthInterceptor

Middleware for authentication using a token provider. This middleware validates the authentication token by comparing it with the defined protected routes. Additionally, it uses a global logger to record information about unauthorized requests.

Parameters

TokenProvider

• Type: AuthProviderInterface
• Description: Implementation of the token provider. Examples of implementations include CognitoProvider.

ConsoleLogger

• Type: LoggerInterface
• Description: Logger instance used to record logs in the system.

Functionality

1. Initializes the global logger using LoggerSingleton.initialize(ConsoleLogger).
2. Checks if the current route is a public route. If it is, access is allowed directly.
3. Validates the token provided in the authorization header.
4. If the token is invalid:
   • Uses the logger to record the unauthorized attempt.
   • Returns a response with the status 401 Unauthorized.
5. If the token is valid:
   • Allows the request to continue by calling next().

Return

A middleware function compatible with frameworks like Express.

Usage Example with Express

import ConsoleLogger from './logger/console.logger';
import express from 'express';
import AuthInterceptor, { CognitoProvider } from 'auth-interceptor-lib';

const app = express();

// Initialize the global logger, type LoggerInterface exported by: import { LoggerInterface } from 'auth-interceptor-lib'
const logger = new ConsoleLogger();

// Initialize the AuthInterceptor with the TokenProvider and Logger
const authMiddleware = AuthInterceptor(new CognitoProvider(), logger);

// Use the middleware in the application
app.use(authMiddleware);

Usage Example with NestJS

import { MiddlewareConsumer, Module, NestModule } from '@nestjs/common'
import AuthProvider, { CognitoProvider } from 'auth-interceptor-lib';
import { ConsoleLogger } from '@/@core/infra/middlewares/logger';

@Module({
  imports: [],
  providers: [],
})

export class AppModule implements NestModule {
  configure(consumer: MiddlewareConsumer) {
    const userPoolId = process.env.USER_POOL_ID || '';
    if (!userPoolId) {
      throw new Error('USER_POOL_ID is not set in the environment variables.');
    }
    consumer
      .apply(AuthProvider(new CognitoProvider(userPoolId), new ConsoleLogger()))
      .forRoutes('*');
  }
}