title: How to listen to changes in Firestore with ESP8266?
body: <p>How do i listen to data changes in Firebase Cloud Firestore with ESP8266? So far i have managed to connect ESP8266 with firestore to read and post data to Firestore using the REST API, but instead of constantly reading data from Firestore, I want to listen to an event when the data changes in Firestore.</p>
  <p>In short, I want to have a stream open  where i am listening for changes in Firestore.</p>
  <p>This can be done with Firebase Real-time database, but i haven't found examples for Firestore.</p>
  <p>Here is an example of what i am trying to do, but with real-time database: <a href="https://github.com/mobizt/Firebase-ESP8266/blob/master/examples/Stream/Stream.ino" rel="nofollow noreferrer">https://github.com/mobizt/Firebase-ESP8266/blob/master/examples/Stream/Stream.ino</a></p>