FireStore create a document if not exist

Question

I want to update a doc like this:

db.collection(\'users\').doc(user_id).update({foo:\'bar\'})

However, if the doc user_id does not exists,

Answer 1

If you need things like created and updated timestamps, you can use this technique:

let id = "abc123";
let email = "john.doe@gmail.com";
let name = "John Doe";
let document = await firebase.firestore().collection("users").doc(id).get();
if (document && document.exists) {
  await document.ref.update({
    updated: new Date().toISOString()
  });
}
else {
  await document.ref.set({
    id: id,
    name: name,
    email: email,
    created: new Date().toISOString(),
    updated: new Date().toISOString()
  }, { merge: true });
}

This will create the document if it doesn't exist with created and updated timestamps, but only change the updated timestamp if it exists.