Firebase check if database exists - node.js

Question

I have a firebase database of form: https://imgur.com/ar8A3DN
I would like two functions:
1. refExists, check if any child exists in database. So that
refExists('datasets') = true
refExists('foo') = false
createChild that creates a new child.
My firebase database instance is declared via:
const accountKeyPath = path.join(__dirname, 'path/to/serviceAccountKey.json')
const accountKey = require(accountKeyPath);
const firebaseAdmin = admin.initializeApp(accountKey);
const dbRef = firebaseAdmin.database().ref('datasets');
The interesting thing is that dbRef and this code which should return an error:
const badRef = firebaseAdmin.database().ref('foo')
both output the same thing. So it's unclear how to check the existence of foo when ref('datasets') and ref('foo') behave the same way.

Answer 1

The way to check whether an element exists is by trying to retrieve a snapshot of it - if the snapshot returns null then the element does not exist.
Adding elements is as simple as calling set on the desired element path with a data object.
function refExists(path) {
firebaseAdmin.database().child(path).once('value', (snap) => {
if (snap.val() !== null) {
console.log('ref exists');
}
});
}
function addRef(newPath, data) {
firebaseAdmin.database().child(newPath).set(data);
}