Firestore - typescript has no access to `snapshot._document.createTime.timestamp`

[davidbielik]

Operating System

any

Browser Version

any

Firebase SDK Version

10.1.0

Firebase SDK Product:

Firestore

Describe your project's tooling

Using typescript:

import {
  CollectionReference,
  DocumentData,
  collection,
  getFirestore,
} from 'firebase/firestore';

const firestore = getFirestore({...});

export const getCollectionRef = <T = DocumentData>(collectionName: string) => {
  return collection(firestore, collectionName) as CollectionReference<T>;
};

Describe the problem

Typescript definitions do not provide a way to access the snapshot._document.createTime property.

Steps and code to reproduce issue

getDocs(collection(firestore, 'users') as CollectionReference<{foo: string}>).then(snapshots => {
  // @ts-expect-error missing typescript definition
  snapshots.docs[0]._document.createTime;
})

but the _document is defined:

[dconeybe]

Hi @davidbielik. Thank you for the bug report. Note that _document is not part of Firestore's public interface (it's a "private" variable). As a result, the behavior and even presence of _document is not guaranteed and we do not support using it directly. So, unfortunately, I cannot give guidance to using it correctly.

However, for createTime specifically, I can say that we intentionally do not expose it from the public API surface. This is because it doesn't have a defined meaning when the document has never been retrieved from the server, such as if the document was created by the client while offline and is served from the local cache.

[davidbielik]

Understood, thanks!