Deleted Firestore documents still being retrieved

Question

I have deleted some documents through a batch delete from a trigger in Cloud Functions. The console shows them as being deleted, however, my app still retrieves the docs! Th

Answer 1

Documents remain fetchable for a while after deletion. Their existence status rely on the DocumentSnapshot property - 'exists' and can be read and filtered in the pipe with snapshotChanges() method for docs and collections. See the example below:

...
.snapshotChanges()
      .pipe(
        map((actions: DocumentChangeAction[]) => {
          return actions
            .filter((a: DocumentChangeAction) => a.payload.doc.exists)
            .map((a: DocumentChangeAction) => {
              const data: T = {...a.payload.doc.data() as {}} as T;
              data['id'] = a.payload.doc.id;
              return data;
            });
        })
      );