Trying to delete a multi-path firestore field document with the batch method

Question

I'm trying to delete a field document with multi-path location with the firestore batch method. I used to do it with the update method on Real Time Database. Now I don't really know how to do it on Firestore.

deleteVenueFromEvent(event) 
{
var eventkey       = event.$key;
var venuekey       = event.venue.venuekey;

var batch          = this.afs.firestore.batch();

var eventRef       = this.eventCollection.doc(eventkey).ref;    
batch.update(eventRef, { venue: null });

var deleteVenueRef = this.venueCollection.doc(venuekey).collection('events').doc(eventkey).ref;
batch.delete(deleteVenueRef);  

batch.commit().then(function() {console.log('Batch Delete')});
}

Answer 1

I find the way to do it with the following code :

var deleteVenueRef = this.venueCollection.doc(venuekey).ref;
batch.update(deleteVenueRef, {['events.' + eventkey] :firebase.firestore.FieldValue.delete()});