Firebase persistance - onDisconnect with multiple browser windows

Question

We\'re writing an app that monitors online presence. There are multiple scenarios where we need the user to have more than one browser window open. We\'re running into a probl

Answer 1

Another simple solution (Using angularfire2, but using pure firebase is similar):

const objRef = this.af.database.list('/users/' + user_id);
const elRef = objRef.push(1);
elRef.onDisconnect().remove();

Each time a new tab is opened a new element is added to the array. The reference for "onDisconnect" is with the new element, and only it is excluded.

The user will be offline when this array is empty.