Is there a way to get email or text notifications each time data is written to my Google Cloud Firestore bucket? - firebase

Question

I have a google cloud bucket and firebase writes my app data there. I would like to monitor my data, and have any new update (write) to my firebase database it sent via a text or email to me. I currently have Twilio set up on Nodejs to send texts on Firebase and my code is:
const functions = require('firebase-functions');
var twilio = require('twilio');
const admin = require('firebase-admin');
admin.initializeApp();
var accountSid = 'account id'; // Account SID from www.twilio.com/console
var authToken = 'account token'; // Auth Token from www.twilio.com/console
var client = new twilio(accountSid, authToken);
exports.useWildcard = functions.firestore
.document('comments/{commentContent}')
.onWrite((change, context) => {
client.messages.create({
body: context.params.commentContent,
to: '[phone]', // Text this number
from: '[phone]' // From a valid Twilio number
})
.then((message) => console.log(message.sid));
});
Currently, I would like to build it out for just the comments document, which are organized inside firebase through comments/{commentContent}. Later, I would like to expand to other trees. I am however, unsure if the above will run each time there is a write to my comments tree. Does it require the firebase-admin module as I have put above? Thanks!

Answer 1

Yes, the onWrite method will not only run when there is a write to the comments tree, but will also be triggered by any change in any document and on the deletion of a document. This means that right now your code will responde in the same way to any of the above cases, and this could cause problems, especially in the case of a document being deleted since it will try to send a comment that doesent exist and will likely get some null exceptions.
Said that you have different solutions.
If you only want the function to react to a new comment, but not to an update or deletion you should use onCreate trigger instead of onWrite.
If you also want to handle a comment update notification you can use both onCreate and onUpdate, but sending different messages by doing something like:
exports.useWildcardCreate = functions.firestore
.document('comments/{commentContent}')
.onCreate((change, context) => {
client.messages.create({
body: context.params.commentContent,
to: '[phone]', // Text this number
from: '[phone]' // From a valid Twilio number
})
.then((message) => console.log(message.sid));
});
exports.useWildcardUpdate = functions.firestore
.document('comments/{commentContent}')
.onUpdate((change, context) => {
const newComment = change.after.data();
const previuosComment = change.before.data();
client.messages.create({
body: 'The comment ${previuosComment} has been changed to ${newComment}',
to: '[phone]', // Text this number
from: '[phone]' // From a valid Twilio number
})
.then((message) => console.log(message.sid));
});
At last if you also need to notify when a comment has been deleted you should use onWrite method but differentiating between the 3 different cases as shown below:
exports.useWildcard = functions.firestore
.document('comments/{commentContent}')
.onWrite((change, context) => {
var textBody;
const oldComment = change.before.data();
const newComment = change.after.data();
if (change.after.exists == false) { // comment has been deleted
textBody = 'The comment ${oldComment} has been deleted';
}
else if (oldComment != newComment) { // comment has been updated
textBody = 'The comment ${oldComment} has been changed to ${newComment}';
}
else { // if its not an update or a deletion its a new comment
textBody = newComment;
}
client.messages.create({
body: textBody,
to: '[phone]', // Text this number
from: '[phone]' // From a valid Twilio number
})
.then((message) => console.log(message.sid));
});
Finally require('firebase-admin') is needed since it will allow you to interact with Firebase from privileged environments. Here you can find all the information to the Firebase Admin SDK