Solana Wallet Auth: A FullStack example

This example uses Solana's wallet adapter to sign messages and verifies their signatures on the backend, allowing for a lean way to authenticate users without the need for web2 credentials like email/password combinations or social providers, in this scenario all you have to do is connect your wallet and sign interaction messages to be properly authenticated.

How to run

Backend

cd wallet-backend
yarn && yarn dev

Frontend

cd wallet-frontend
yarn && yarn dev

Technology stack for this example

Most of the technologies used in this example are production ready, however, be sure to check them and remember to switch LowDB for a proper database.

Backend

• NodeJS, Express, Typescript, LowDB (Local JSON file, only for testing), TweetNaCL.
• GraphQL example coming soon.

Frontend

• React, Typescript, Vite, Solana-Wallet-Adapter, Tailwind.

Notes

Validation on the backend happens using the library tweetnacl, but some additional checks were added, like action and message expiration.

The files you want to check are:

• @wallet-backend/src/middleware/web3Auth.ts
• @wallet-frontend/src/lib/api/web3Posts.ts

Where web3Auth.ts defines a simple, yet powerful authorization middleware that extracts the authorization headers and validates, then parses the message to perform some additional checks and the web3Posts.ts axios client exemplifies a good set of UX patterns, like reusing a token for "skip" requests (Requests that skip action checks).

Here's a diagram of how simplified is this authentication method

Reference read

• Solana Wallet Adapter - How can I sign and verify messages?
• Phantom Wallet - Signing a Message
• TweetNaCL - Verfiy message signature
• Improve user authentication with Web3 wallets
• Build a Web3 authentication flow with React, Ether.js, and Ceramic