Using the same firebase project for multiple domains

Question

I want to use the same firebase project for multiple websites. How do I get this working on browser and cloud functions?

Browser

firebase.initializeApp({
  apiKey: "***********************",
  authDomain: "domain1.com",
  databaseURL: "https://domain.firebaseio.com",
  projectId: "domain",
  storageBucket: "",
  messagingSenderId: "-----------",
  appId: "-------------"
});

If I change "domain1.com" to "domain2.com", will it work without issues? What happens to registered users in firebase? Will it be a combination of domain1.com and domain2.com?

Cloud functions

Will admin.database() return the domain.firebaseio.com RTDB irrespective of users logging into domain1.com or domain2.com? What happens to:

const tokenId = req.get('Authorization').split('Bearer ')[1];
admin.auth().verifyIdToken(idToken);

Thanks!

score 0 · Accepted Answer · answered Oct 23 '20 at 16:18

0

The hostname or domain name of your site doesn't much matter to Realtime Database. It is only an issue for Firebase Authentication. As long as you've added each domain to the project in the Firebase console, things will work as you expect with the same configuration for each site. Your sites will share the same set of users for the one project they are connected to.

answered Oct 23 '20 at 16:18

Doug Stevenson

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Got it! I assume the user has to reauthenticate, when he moves from domain1 to domain2? – Réti Opening Oct 23 '20 at 16:49
I would assume so, because each domain's data and local storage is sandboxed. If you have a way of sharing data between them, you might be able to get around that somehow. – Doug Stevenson Oct 23 '20 at 16:50
By encrypting and passing the Bearer token from domain1 to domain2? – Réti Opening Oct 23 '20 at 16:54
No, I mean between each other, before a backend is involved. – Doug Stevenson Oct 23 '20 at 17:00

Using the same firebase project for multiple domains

1 Answers1