使用Node.js后端持久登录Firebase

Question

When I've looked up how to check if the user requesting a certain view is logged in, many people suggest using firebase.auth().currentUser , but when I read the docs, it says that firebase.auth().currentUser just shows you if any user is logged in which doesn't really help me when I'm getting a request to my Node server, and I want to see if the user is logged in.

So what is the idiomatic way to let a user login in Firebase, keep them logged in, and have a function to tell you if they're logged in?

Answer 1

Assuming that the user is authenticating to Firebase on the client side, the typical approach is for the client to pass an ID token to the server to identify the Firebase user for the session. See this documentation for details on how to generate the ID token on the client and then verify it on the server.