Authentication Server with Express.js

This repository contains a simple authentication server implemented using Express.js, JWT (JSON Web Tokens), and bcrypt for password hashing. The server provides endpoints for user sign up and sign in, generating a token upon successful authentication.

Features

• User registration: Users can sign up by providing a unique username and password. The server checks if the username already exists and returns an error if it does.
• User authentication: Users can sign in by providing their username and password. The server verifies the credentials and returns an authentication token upon successful login.
• Token-based authentication: JWT (JSON Web Tokens) are used to generate and validate authentication tokens. The tokens are signed using a secret key, ensuring their authenticity.
• Basic password hashing: Passwords are hashed using bcrypt, a secure password-hashing algorithm. This ensures that even if the server is compromised, user passwords remain protected.
• CORS support: Cross-Origin Resource Sharing (CORS) is enabled, allowing the server to handle requests from different origins.
• Environment variable configuration: The server supports environment variables for configuration, allowing for easy customization of settings such as the secret key.

Prerequisites

Before running the server, ensure you have the following dependencies installed:

• Node.js
• npm (Node Package Manager)

Installation

1. Clone this repository to your local machine.

2. Navigate to the project directory in your terminal.

3. Run npm install to install the required dependencies.

4. Create a .env file in the project root and define the following environment variable:

   SECRET_KEY=<your_secret_key>
   

   Replace <your_secret_key> with your desired secret key for JWT token signing.

Usage

1. Start the server by running npm start in the project directory.
2. The server will be running on http://localhost:3000.

API Endpoints

• POST /api/signup - Register a new user.

  • Request body: { "username": "<username>", "password": "<password>" }
  • Response: { "message": "User created successfully", "token": "<generated_token>" }

• POST /api/signin - Authenticate a user.

  • Request body: { "username": "<username>", "password": "<password>" }
  • Response: { "message": "Sign in successful", "token": "<generated_token>", "user": "<username>" }

Security Considerations

• It is recommended to use HTTPS when deploying this server to ensure secure communication between clients and the server.
• In a production environment, consider using a secure session management system to handle user sessions and protect against session hijacking attacks.

License

This project is licensed under the MIT License.