One-Time Token Login with Spring Security

One-time tokens can significantly enhance security in your Spring applications. Here’s a quick guide on implementing a one-time token login system:

1. Generate a Token: When a user triggers the login process, generate a unique token. You can utilize java.util.UUID for this purpose:

   String token = UUID.randomUUID().toString();
   

2. Send Token via Email: Email the token to the user’s registered email address. This ensures only they can log in.

3. Validate Token: When the user clicks the login link, validate the token. If valid, allow access; if not, deny entry.

4. Token Expiry: Ensure that the token expires after a certain time, usually within a few minutes, to enhance security. You could use a database or in-memory store to manage token states.

5. Cleanup: After successful login or expired tokens, remove them from your store to prevent misuse.

Implementing this approach protects user sessions from unauthorized access while ensuring a smooth login experience! 😊🔐