Sync Realtime DB with Authentication users list

Question

I'm creating all users from Firebase console, Now I wanted copy all users to realtime db under users node.

Below is my Google cloud function

exports.getAllUsers = functions.https.onRequest((req, res) => {
  cors(req, res, () => {
    app.auth().listUsers(1000)
      .then((listUsersResult) => {
        var db = admin.database();
        var ref = db.ref("users");
        const usersRef = ref.child('users');
        usersRef.set(listUsersResult,  { merge: true } );

        ref.once("value", function (snapshot) {
          console.log(snapshot.val());
        });


        // admin.database().ref('users').set(listUsersResult, { merge: true })
        res.send(listUsersResult);
      })
      .catch(function (error) {
        console.log('Oh no! Firebase listUsers Error:', error);
      });
  });
});

By using firebase-admin, I could get all the users list but When I tried to update the DB i'm getting the below error

Oh no! Firebase listUsers Error: Error: Reference.set failed: onComplete argument must be a valid function.

How can I fix this?

The `set()` and `once()` methods are asynchronous. You need to use `then()` or async/await to get the results. — Renaud Tarnec, Nov 07 '22 at 07:46

score 1 · Accepted Answer · answered Nov 07 '22 at 15:03

You're passing { merge: true } to the call to set, but that option only exists in the Firestore API - not in the API of the Realtime Database. So:

usersRef.set(listUsersResult);

In addition, you need to handle the asynchronous nature of set and once as Renaud commented. So combining the above with that gets to:

usersRef.set(listUsersResult)
.then(() => {
  ref.once("value", function (snapshot) {
    console.log(snapshot.val());
    res.send(listUsersResult);
  });
});

That leaves the fact that your usersRef refers to /users/users in the database, which you'll probably also want to fix.

Sync Realtime DB with Authentication users list

1 Answers1