C++ Authentication

Introduction to JWT in C++

JSON Web Tokens (JWT) provide a compact, URL-safe means of representing claims to be transferred between two parties. In C++, JWT can be used to secure API endpoints by ensuring that each request is authenticated properly.

JWTs are widely used due to their simplicity and the fact that they can be verified easily on the server side without maintaining session state.

Setting up a JWT Library in C++

To work with JWTs in C++, you need to include a JWT library. One popular choice is jwt-cpp, which is a header-only library providing tools to encode, decode, and verify JWTs.

First, clone the jwt-cpp repository:

Encoding a JWT in C++

Once the library is set up, you can create and sign a JWT using the following code. This example demonstrates creating a token with a payload containing the user's ID and the token's expiration time.

Decoding and Verifying a JWT

Decoding and verifying a JWT is crucial to ensure that the token is valid and has not been tampered with. Here's how you can decode a JWT and validate its signature in C++:

Best Practices for Using JWT in C++

• Keep your secret key safe: Ensure that your secret key is stored securely and not hardcoded in your source code.
• Set appropriate expiration times: Tokens should have a reasonable expiration time to limit the window of risk if the token is compromised.
• Use HTTPS: Always use HTTPS to encrypt the data between the client and server.