Detect if Firebase connection is lost/regained

Question

Is there a strategy that would work within the current Firebase offering to detect if the server connection is lost and/or regained?

I\'m considering some offline co

Answer 1

I guess this changed in the last couple of months. Currently the instructions are here: https://firebase.google.com/docs/database/web/offline-capabilities

In summation:

var presenceRef = firebase.database().ref("disconnectmessage");
// Write a string when this client loses connection
presenceRef.onDisconnect().set("I disconnected!");

and:

var connectedRef = firebase.database().ref(".info/connected");
connectedRef.on("value", function(snap) {
  if (snap.val() === true) {
    alert("connected");
  } else {
    alert("not connected");
  }
});

I'll admit I don't know a lot about how references are set, or what that means (are you making them out of thin air or do you have to have already created them beforehand?) or which one of those would trigger something on the server as opposed to something on the front end, but if the link is still current when you read this, a little more reading might help.