Firestore：如何从服务器端获取更新流？

Question

tldr: I need to have Google Cloud Functions on my own backend.

I write application, which uses firebase (especially firestore) as a transport layer between my own backend written on nodejs and client applications.

Sometimes, I need to catch some events from client on backend, but i want to avoid perform http queries directly to my backend (because I need to catch offline status, and other problems). It is better to made some changes in firestore documents, catch that changes on my backend and perform some business logic.

As for now, It can be solved with Cloud Functions, but this solution is not acceptable, because of delay between event and function invocation, and lack of invocation order.

Yet another solution, which is currently used in my project, is to making some changes to firestore document, and adding extra document, called "event" to other collection. On a server side, using firebase-admin sdk, I subscribe to that "events" collection and get realtime updates of it.

This work great, but looks like overcomplicated. Is there any way to subscribe from my backend to get all updates of all documents of firestore? Ideal solution is to subscribe to updates, as it done in Cloud Functions: https://firebase.google.com/docs/functions/firestore-events?authuser=0

Answer 1

The client and server SDKs don't have this capability. Cloud Functions is really your only way to get notified of changes in Firestore that match a wildcard pattern.