How to check if a cloud firestore document exists when using realtime updates

Question

This works:

db.collection(\'users\').doc(\'id\').get()
  .then((docSnapshot) => {
    if (docSnapshot.exists) {
      db.collection(\'users\').doc(\'id\')         


        

Answer 1

Your initial approach is right, but it may be less verbose to assign the document reference to a variable like so:

const usersRef = db.collection('users').doc('id')

usersRef.get()
  .then((docSnapshot) => {
    if (docSnapshot.exists) {
      usersRef.onSnapshot((doc) => {
        // do stuff with the data
      });
    } else {
      usersRef.set({...}) // create the document
    }
});

Reference: Get a document