Cloud Functions and Firestore does not go up the root in Firebase - firebase

Question

// 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(functions.config().firebase);
exports.giveCard = functions.firestore
.document('Profiles/{profileId}/cards/{cardsId}/_given/{_givenID}')
.onWrite((event) => {
// Get the field values of what I am working with
const oldGiven = event.data.previous.data()['given'];
const newGiven = event.data.data()['given'];
// Get the cardID to make sure that is there
const cardID = event.params.cardsId;
// An array to go through
const give_profiles = event.data.data()['given_profiles'];
// error cardDatatwo is returned as undefined
const cardDatatwo = newGiven.parent;
// error cardDatathree is returned as undefined
const cardDatathree = event.data.ref.root
// // error cardDatafour cannot read propoerty of undefined
// const cardDatafour = cardDatathree.child('Profiles/{profileId}/cards/{cardsId}')
// error cardDatafive 'The value of cardfive is DocumentReference...
const cardDatafive = event.data.ref.firestore.doc('Profiles/{profileId}/cards/{cardsId}');
// Check that the values have changed
if (newGiven == oldGiven) return;
if (newGiven !== undefined) {
console.log('The old value of given is', oldGiven);
console.log('The new value of given is', newGiven);
console.log('The value of the card is', cardID);
console.log('The value of the cardtwo is', cardDatatwo);
console.log('The value of the cardthree is', cardDatathree);
// console.log('The value of the cardfour is', cardDatafour);
console.log('The value of the cardfive is', cardDatafive);
for (var profile of give_profiles) {
console.log(profile);
};
return;
}
return console.log("No given value");
});
I am having great difficulty in getting the root for Firestore working with Cloud Functions. It works differently of course.
I am try to get a value up the path towards the root after an onUpdate has been fired further down.
.parent does not work
functions.database.ref of course does not work as that's the realtime database
and cannot use
firebase.firestore() is also not working in node
and event.data.ref.firestore.doc comes back as undefined.
I am sure have gone through every option.
Hope you can help.
Wo

Answer 1

According to the documentation, you can access collections via firestore, like this:
exports.giveCard = functions.firestore
.document('Profiles/{profileId}/cards/{cardsId}/_given/{_givenID}')
.onWrite((event) => {
// other code
const ref = event.data.ref.firestore.doc('your/path/here');
return ref.set({foo: 'bar'}).then(res => {
console.log('Document written');
});
});
You can use firestore to build a path to whatever part of the database you're seeking to access. You can also use event.data.ref.parent, like so:
exports.giveCard = functions.firestore
.document('Profiles/{profileId}/cards/{cardsId}/_given/{_givenID}')
.onWrite((event) => {
// other code
const parentref = event.data.ref.parent;
const grandparentref = parentref.parent; // gets to cardsId
return grandparentref.set({foo: 'bar'}).then(res => {
console.log('Document written');
});
});