How is createTime and updateTime set?

[bhaskarmurthy]

I'm trying to understand how the createTime and updateTime values are set.

When I use the addDoc method, it seems to automatically generate the timestamp - which is accessible in the createTime and updateTime fields from the snapshot.

However - when I go to Firestore, there are no such fields in the document.
Where is this value stored?

Example:

type Organization = {
  name: string;
};
type OrganizationMeta = MetaTypeCreator<Organization, 'organizations'>;

const db = getFirestore();
const firelord = getFirelord<OrganizationMeta>(db, 'organizations');
const organization: Organization = { name: "Hello, world" };
const ref = await addDoc(firelord.collection(), organization);
const snap = await getDoc(firelord.doc(ref.id));

console.log('createTime', snap.createTime); // this is somehow set
console.log('updateTime', snap.updateTime); // this is somehow set
console.log('data', snap.data()); // this does not contain timestamp properties

// also checking Firestore console, there are no timestamp properties in the document

Thanks!

[tylim88]

Firelord doesnt set them, in fact this is the first time i see something like these

They seem to be meta data, that is why you cant find them in data()

I think they are hidden API of official SDK because they cant be found in official documentation https://firebase.google.com/docs/reference/node/firebase.firestore.DocumentSnapshot

[tylim88]

update: I found them

https://cloud.google.com/nodejs/docs/reference/firestore/latest/firestore/documentsnapshot#_google_cloud_firestore_DocumentSnapshot_createTime_member

they can only be accessed from admin sdk, they are meta data, not part of your data

[bhaskarmurthy]

This is amazing - never knew this existed. Thanks for looking into this!