I've recently tried to update .WriteOn cloud function into a scheduled cloud function for my firebase app. The objective is to run a function every 4 days that goes out deletes messages that are over 2 days old. This worked perfectly for the .WriteOn function but of course that meant the function was executed every time a message was created; which was overkill. Here is the function I have in my index.js file...
// The Cloud Functions for Firebase SDK to create Cloud Functions and setup triggers.
const functions = require('firebase-functions');
// The Firebase Admin SDK to access the Firebase Realtime Database.
const admin = require('firebase-admin');
admin.initializeApp()
exports.scheduledFunction = functions.pubsub.schedule('every 96 hours').onRun(async (context) => {
const ref = admin.database().reference('messages/{pushId}');
var now = Date.now();
var cutoff = now - 24 * 60 * 60 * 1000;
var oldItemsQuery = ref.orderByChild('timeStamp').endAt(cutoff);
return oldItemsQuery.once('value', function(snapshot) {
// create a map with all children that need to be removed
var updates = {};
snapshot.forEach(function(child) {
updates[child.key] = null
});
// execute all updates in one go and return the result to end the function
return ref.update(updates);
});
});
Here is the execution error I'm reading on my Firebase Functions console...
scheduledFunction TypeError: admin.database(...).reference is not a function
The error message is telling you that this line of code is calling a method that doesn't exist:
const ref = admin.database().reference('messages/{pushId}');
In fact, there is no method called "reference" on the Database object returned by admin.database(). Using the API documentation, you can see that database() returns a Database object which further extends a different Database. In there, you'll see that there is a ref() method. There is no reference(). Maybe that's what you meant to use.
const ref = admin.database().ref('messages/{pushId}');
Also, this is what you'll see in the example code in the documentation. Please review that to make sure you're following the correct examples for JavaScript.