[SOLVED] How to remove a nested property from an object in Firestore

How to remove a nested property from an object in Firestore

my firestore stores user data as below:

users (collection)
   uid-123 (document one per user)
     profile:
        name: 'My Name'
        options: {
                    x: 1,
                    y: 2,
                    z: 3
                 }

In a situation i want to remove y:2 from the profile.options. I am using like below:

async updateUserProfileMerged(uid: string, payload: any) {
      try{
          const userDocRef = doc(this.firestore, 'users/' + uid);
          return setDoc(userDocRef, Object.assign({},{"profile": payload}), { merge: true     });
        }catch(err){
          console.log("error in updateUserProfileMerged in data.service.ts:", err)
        }
    }

The passed payload in this case is:

 options: {
            x:1,
            z: 3
          }

This does not remove y as it is passing merge true. if i set merge to false then it will override the entire profile object. so how do i only override options?

Solution

If you want to delete a field in a document, you should use the documented deleteField function as the value for a field update. And, since you're using a nested field, you should use dot notation to specify the name of the field to delete. Given these two things, your code should end up looking more like this:

import { doc, updateDoc, deleteField } from "firebase/firestore";

const userDocRef = doc(this.firestore, 'users/' + uid);

await updateDoc(userDocRef, {
    "profile.options.y": deleteField()
});

Your other option is to simply re-write the entire document using setDoc, omitting the field that should not be present.