如何从节点 js 应用程序向客户端发送实时更新

Question

I am using firebase realtime database and firebase firestore in my web app and everytime a user updates their data firebase is sending that data to my server and I want to send that data to client how do it do it because with my current code it is giving me res.setHeader error

Answer 1

What you're looking for is called realtime updates, which use onSnapshot .

Here is the relevant tutorial https://firebase.google.com/docs/firestore/query-data/listen

The example there for NodeJS is:

const doc = db.collection('cities').doc('SF');

const observer = doc.onSnapshot(docSnapshot => {
  console.log(`Received doc snapshot: ${docSnapshot}`);
  // ...
}, err => {
  console.log(`Encountered error: ${err}`);
});