Google OAuth2 in Svelte + FastAPI: Create a Session Cookie from JWT
Table of Contents Introduction What I Implement Frontend implementation with Svelte Backend implementation with FastAPI Conclusion Introduction I have implemented Google Sign-In functionality in a sample website built using Svelte and FastAPI. There are various methods to authenticate users in the backend API server after a successful Google Sign In. One common approach is to send the JWT received from Google in the request header as Authorization: "Bearer: JWT", and if the JWT is valid, authorization to access resources is granted. Another typical method involves issuing a JWT on the backend and using it for user authentication in the Authorization header. However, using JWT directly for session management poses a challenge in immediate invalidation if the JWT is leaked. Reference: Stop using JWT for sessions . Therefore, I implemented a method in which, following the receipt of the JWT from Google, FastAPI assigns a new session_id. This session_id is set in a co