Firebase - Firestore - get key with collection.add()

Question

I am facing a problem with the new Firestore from Firebase.

Situation: I have a collection('room')

I create room with collection('room').add(room)

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What I'm trying to do: I need to update a room.

For this, I use: collection('room').doc(ROOM_ID).update(update)

So I need to add ROOM_ID in the document in my collection:

|room     ROOM_ID         id:ROOM_ID,         someContent: ForTheQuery 

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Is there a possible way to achieve that?

An alternative is to create myself a generated ID with:

collection('room') .doc(someId) .set({     id: someId,     someContent: ForTheQuery }); 

but i want to avoid it.

Answer 1

You can use doc() to create a reference to a document with a unique id, but the document will not be created yet. You can then set the contents of that doc by using the unique id that was provided in the document reference:

const ref = store.collection('users').doc() console.log(ref.id)  // prints the unique id ref.set({id: ref.id})  // sets the contents of the doc using the id .then(() => {  // fetch the doc again and show its data     ref.get().then(doc => {         console.log(doc.data())  // prints {id: "the unique id"}     }) })