Building Secure APIs with Google Token Verification in Nest.js: An Expert’s Perspective

In today’s digital landscape, ensuring the security of user authentication is of paramount importance for any web application. Nest.js, a popular backend framework for building scalable and maintainable APIs with Node.js, provides robust support for implementing authentication mechanisms, including the integration of Google Token Verification.

In this article, we will dive into the world of Google Token Verification in Nest.js, best practices, and implementation strategies.

Install the library

npm install google-auth-library --save

To implement Google Token Verification in Nest.js, you’ll need to create a controller file and import your services into it.

In the controller, you can define and initialize your services in the constructor, making them available for use in your routes and handlers.

Additionally, to ensure proper validation of incoming requests, you’ll need to create a Data Transfer Object (DTO) that handles request validation. This step is crucial for maintaining the integrity and security of your application.

auth.controller.ts

import { AuthService } from './auth.service';
import { AuthGoogleLoginDto } from './auth.dto';

export class AuthController {
  constructor(private readonly authService: AuthService) {}

  @Post('/google-login')
  @HttpCode(200)
  googleLogin(@Body(ValidationPipe) body: AuthGoogleLoginDto) {
    return this.authService.googleLogin(body);
  }
}

Next, let’s focus on defining the Data Transfer Object (DTO) for handling request validation.

The DTO serves as a structure or blueprint that defines the expected shape of incoming requests and allows you to validate and manipulate the data before processing it further.

auth.dto.ts

export class AuthGoogleLoginDto {
  @IsNotEmpty()
  @IsString()
  googleTokenId: string;
}

The final step in implementing Google Token Verification in Nest.js is to create the services that will handle the verification of the Google token ID.

These services will contain the necessary logic to validate the token, authenticate the user, and ensure the security of the verification process.

By leveraging the code provided, you can integrate the Google token verification functionality seamlessly into your Nest.js application.

const {OAuth2Client} = require('google-auth-library');

async googleLogin(body: AuthGoogleLoginDto) {
  const client = new OAuth2Client(CLIENT_ID);
  async function verify() {
    const ticket = await client.verifyIdToken({
        idToken: body.googleTokenId,
        audience: process.env.CLIENT_ID
    });
    const payload = ticket.getPayload();
    console.log(payload , "payload")
  }
  verify().catch(console.error);
  return payload
}

Incorporating a package into the front-end of your application can greatly enhance its functionality.

If you’re interested in adding Google Login to your front-end, you’re in luck! I’ve written a separate blog specifically dedicated to this topic. In that blog, you’ll find detailed instructions on how to integrate Google Login into your front-end code, allowing users to log in to your application using their Google accounts.

Be sure to check out that blog to learn how to seamlessly implement Google Login in your front-end and provide a convenient and secure login option for your users, Click Here.

Conclusion:

In conclusion, implementing Google Token Verification in Nest.js can greatly enhance the security and authentication mechanism of your application. By following the steps outlined in this blog, including creating a Nest.js controller, defining a DTO for request validation, and creating services for handling Google token verification,

By following best practices and leveraging the power of Google Token Verification, you can enhance the security of your Nest.js application and provide a reliable and secure authentication process for your users.