A complete Web3 authentication system with wallet connection, signature verification, and token balance display.

• Connect to MetaMask wallet
• Sign messages to verify wallet ownership
• JWT-based authentication
• Protected routes
• Display ETH, USDT, and USDC balances

• React.js
• React Router for navigation
• Tailwind CSS for styling
• ethers.js for Ethereum interaction
• Axios for API requests

• Go (Golang)
• Gin web framework
• JWT for authentication
• PostgreSQL database

web3auth/
│
├── frontend/
│   ├── public/
│   │   ├── index.html
│   │   └── favicon.ico
│   │
│   ├── src/
│   │   ├── components/
│   │   │   ├── ConnectWallet.jsx
│   │   │   └── Dashboard.jsx
│   │   │
│   │   ├── utils/
│   │   │   └── web3.js
│   │   │
│   │   ├── App.jsx
│   │   ├── index.jsx
│   │   └── index.css
│   │
│   ├── package.json
│   └── tailwind.config.js
│
├── backend/
│   ├── cmd/
│   │   └── server/
│   │       └── main.go
│   │
│   ├── internal/
│   │   ├── auth/
│   │   │   ├── handler.go
│   │   │   ├── middleware.go
│   │   │   ├── service.go
│   │   │   └── jwt.go
│   │   │
│   │   ├── user/
│   │   │   ├── handler.go
│   │   │   ├── model.go
│   │   │   └── repository.go
│   │   │
│   │   └── utils/
│   │       ├── db.go
│   │       ├── ethereum.go
│   │       └── middleware.go
│   │
│   ├── migrations/
│   │   └── 001_create_users.sql
│   │
│   ├── go.mod
│   └── go.sum
│
├── docker-compose.yml
└── README.md

• Node.js and npm
• Go (1.16+)
• Docker and Docker Compose
• PostgreSQL (or use the Docker container)

1. Clone the repository

git clone https://github.com/biganashvili/web3auth.git
cd web3auth

2. Start the services with Docker Compose

docker-compose up -d

3. Access the application

• Frontend: http://localhost:3000
• Backend API: http://localhost:8080/api

cd frontend
npm install
npm start

cd backend
go mod download
go run cmd/server/main.go

1. User clicks "Connect MetaMask" button
2. Frontend requests wallet connection via MetaMask
3. Backend generates a random nonce for the address
4. User signs a message containing this nonce
5. Backend verifies the signature cryptographically
6. If valid, a JWT token is issued and stored in localStorage
7. User is redirected to the dashboard where they can see their token balances

MIT

Sergi Biganashvili