How to make Function trigger only onCreate and onUpdate?

Question

I want Cloud Function trigger only when document is create and update. I do not want Cloud Function trigger onDelete.

Is there any trigger for only onCreate and onUpdate without make 2 separate function?

I see Firebase have onWrite, but this trigger also onDelete:

onCreate Triggered when a document is written to for the first time.

onUpdate Triggered when a document already exists and has any value

changed. onDelete Triggered when a document with data is deleted.

onWrite Triggered when onCreate, onUpdate or onDelete is triggered.


Thanks everyone!

Answer 1

You can use onWrite listener with handler that does nothing in case of deletion.

exports.myFunction = functions.firestore
    .document('/abc/{docId}')
    .onWrite((change, context) => {

      // Exit when the data is deleted.
      if (!change.after.exists) {
        return null;
      }

      //TODO: put code here you want to execute for create and update
    });

Answer 2

There are no combination triggers, so you will need to declare two Cloud Functions for this.

But you can implement your actual logic in a single regular function, and then just call that from the two Cloud Functions.

Something like

exports.createUser = functions.firestore
    .document('users/{userId}')
    .onCreate((snap, context) => {
      doTheThing(snap, context);
    });
  
exports.updateUser = functions.firestore
    .document('users/{userId}')
    .onUpdate((change, context) => {
      doTheThing(change.after, context);
    });

function doTheThing(snapshot, context) {
    ...
};