This is a readme file for a web application that provides user authentication features using various technologies for both the backend and frontend. The application allows users to sign up, log in, and log out using their email and password. Below, you will find an overview of the technologies used and the key features of this web application.

• Node.js: The server-side runtime environment.
• Express: The web framework for building the server.
• MongoDB: The database for storing user data.
• Mongoose: An ODM (Object Data Modeling) library for MongoDB.
• bcrypt: A library for hashing and securing passwords.
• dotenv: For loading environment variables.
• cookie-parser: For handling cookies.
• cors: For enabling Cross-Origin Resource Sharing.
• email-validator: For validating email addresses.
• jsonwebtoken (JWT): For creating and verifying JSON Web Tokens.
• nodemon: A development tool for automatically restarting the server during development.

• User Registration: Users can sign up by providing their email and password. The password is securely hashed using bcrypt before being stored in the database. Email addresses are validated using email-validator to ensure they are in the correct format.

• User Authentication: Users can log in with their registered email and password. Upon successful authentication, the server generates a JSON Web Token (JWT), which is stored in a cookie using cookie-parser and cors. This token is used to authenticate the user for accessing protected routes on the server.

• Protected Routes: Certain routes on the server are protected, meaning they require a valid JWT to access. This ensures that only authenticated users can perform certain actions.

• Secure Password Handling: User passwords are securely hashed using bcrypt before being stored in the MongoDB database. This ensures that even if the database is compromised, user passwords remain secure.

• React: The JavaScript library for building user interfaces.
• axios: A library for making HTTP requests to the backend.

• User Interface: The frontend is built using React to provide a user-friendly interface. It includes the following components:

  • Sign-up form: Allows users to create an account.
  • Log-in form: Allows users to log in with their credentials.
  • Log-out button: Allows users to log out.
  • User information display: Shows the user's email and a welcome message when they are logged in.

• State Management: React hooks are used to manage the state of the user's authentication status and JWT. This ensures that the user interface updates appropriately based on the user's login status.

To run this web application locally, follow these steps:

1. Clone the repository to your local machine.

2. Navigate to the project directory in your terminal.

3. Install backend dependencies:

   cd backend
   npm install
   

4. Create a .env file in the backend directory with the following variables:

   MONGODB_URI=<your MongoDB URI>
   JWT_SECRET=<your JWT secret>
   

5. Start the backend server:

   npm start
   

6. Install frontend dependencies:

   cd ../frontend
   npm install
   

7. Start the frontend:

   npm start
   

8. Access the application in your web browser at http://localhost:3000.

Sure! Here’s a sample README file for your project:

This project is a simple login API for SignUp and SignIn.

• Setup node.js server
• Connect the application to the MongoDB
• Create user schema
• JWT (route level Middleware)
• Create Controller
• Create Routes

The following are some requirements for developing these APIs:

• Node.js should be installed on your system.
• MongoDB should be installed as we are using MongoDB as our database.

Node.js is a platform built for easily building fast and scalable network applications. It uses an event-driven, non-blocking I/O model that makes it lightweight and efficient, perfect for data-intensive real-time applications that run across distributed devices.

Express is a minimal and flexible Node.js web application framework that provides a robust set of features to develop web and mobile applications. It facilitates the rapid development of Node-based Web applications.

MongoDB is a cross-platform, document-oriented database that provides high performance, high availability, and easy scalability. MongoDB works on the concept of collection and documentation.

To set up your application:

1. Open any of your editors like Visual Studio Code, Sublime Text, or any other.

2. In the terminal, write npm init.

3. The app will be initialized, and all basic dependencies will be installed. You need to pass a few details if you wish; otherwise, there is no need to do so. The command prompt will look like the following:

4. Now install some dependencies that will be required in developing our APIs like express, mongoose, cookie-parser, bcrypt, dotenv. In the terminal, write:

npm install express mongoose cookie-parser bcrypt dotenv

Use of each module:

• express: Allows you to define routes of your application based on HTTP methods and URLs.
• cookie-parser: It is used for parsing the cookie.
• bcrypt: It is used for hashing and comparing the password.

This web application provides user authentication functionality with secure password handling and a user-friendly frontend built with React. Users can sign up, log in, and enjoy a personalized experience with their email and JWT. The backend is powered by Node.js and Express, while MongoDB stores user data securely. Enjoy using and customizing this web application for your needs!