# README

Golang JWT Authentication Template

This project is a JWT-based authentication template written in Golang. It provides basic routes for user registration, login, logout, and a secure route for fetching all users, using JSON Web Tokens (JWT) to protect endpoints. The project includes a simple custom router and middleware for handling token verification.

Features

User registration and login
Password hashing with bcrypt
JWT token generation and verification
Middleware for protecting routes
Custom routing mechanism
Basic user validation with validator

Technologies Used

Go (Golang)
JWT (github.com/golang-jwt/jwt/v5): For generating and verifying JWT tokens.
bcrypt (golang.org/x/crypto): For password hashing.
Go Playground Validator (github.com/go-playground/validator/v10): For request validation.

Installation

Clone the repository:

git clone https://github.com/yourusername/golangJWTAuthTemplate.git
cd golangJWTAuthTemplate

Initialize the project and install dependencies:
```
go mod tidy
```
Run the server:
```
go run main.go
```

Endpoints

1. Register a new user

Endpoint: /register
Method: POST

Body (JSON):

{
  "email": "[email protected]",
  "password": "password123"
}

Response: User object or validation error.

2. Login

Endpoint: /login
Method: POST

Body (JSON):

{
  "email": "[email protected]",
  "password": "password123"
}

Response: A JWT token is set in an HTTP-only cookie for authentication.

3. Logout

Endpoint: /logout
Method: POST
Description: Logs out the user by invalidating the JWT cookie.

4. Get All Users (Protected Route)

Endpoint: /get-all
Method: GET
Description: Fetches all users. Requires a valid JWT token.

This route is protected with middleware that verifies the JWT token before allowing access.

Middleware

The project includes an authentication middleware to protect sensitive routes. It checks for the JWT token in cookies and verifies it before allowing access to protected routes.

func Auth(next http.Handler) http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        cookie, err := r.Cookie("jwt_token")
        if err != nil {
            http.Error(w, "Token missing in cookie", http.StatusBadRequest)
            return
        }

        token, err := utils.VerifyToken(cookie.Value)
        if err != nil {
            http.Error(w, "Token verification failed", http.StatusBadRequest)
            return
        }

        fmt.Printf("Token verified successfully. \nClaims:%v", token.Claims)
        next.ServeHTTP(w, r)
    })
}

Dependencies

This project uses the following Go packages:

github.com/golang-jwt/jwt/v5: For creating and verifying JWT tokens.
golang.org/x/crypto: For secure password hashing using bcrypt.
github.com/go-playground/validator/v10: For validating user input.

How to Use

Register: Send a POST request to /register with a JSON body containing an email and password.
Login: Send a POST request to /login with valid user credentials to get a JWT token set in the cookies.
Access Protected Routes: Use the /get-all route to access protected resources by passing the JWT token in the cookies.
Logout: Call /logout to invalidate the JWT token and log the user out.