Using Firebase Authentication in NestJS apps

The article details a guide on integrating Firebase Authentication into a NestJS application to create a simple project that allows only authenticated users to access a resource, utilizing Firebase's capabilities to streamline the authentication setup. Firebase provides a suite of services, including databases, authentication, and analytics, which can be incorporated into NodeJS apps using the firebase-admin npm module. NestJS, a popular framework for building server-side applications with TypeScript, is used to structure the project with an Angular-like architecture. The project involves setting up a NestJS application, creating authentication routes with Handlebars for dynamic HTML, and employing Firebase for user login and signup, where users receive a JSON Web Token (JWT) that is validated server-side using firebase-admin SDK. Further, the article explains how to secure routes using Passport and Firebase strategies, which verify JWTs to protect endpoints, exemplified by a resources route serving quotes from "The Simpsons" that is accessible only to authenticated users.