Demo RxJs integration with Firebase

rxjs-firebase-demo.js

var Rx = require('rxjs');
var firebase = require('firebase');
firebase.initializeApp({
  "databaseURL": "https://quiver-two.firebaseio.com",
  "serviceAccount": "./service-account.json"
});

var ref = firebase.database().ref('rxjs-demo');
Rx.Observable.fromPromise(ref.remove())
  .map(function () {
    return Rx.Observable.interval(2000);
  })
  .combineAll()
  .map(function() {  
    return Rx.Observable.from(ref.limitToLast(1).once('value'));
  })
  .mergeAll()
  .subscribe(function (snap) {
    var random = Math.random();
    var keys = Object.keys(snap.val() || {});
    switch (true) {
      case (!keys.length || random < 0.5) && keys.length <= 5:
        Rx.Observable.fromPromise(ref.push({
          random: random
        }))
          .subscribe(function () {
            console.log('pushed');
          });
        break;
      case keys.length > 5 || random < .75:
        Rx.Observable.fromPromise(snap.ref.child(keys[0]).remove())
          .subscribe(function () {
            console.log('removed');
          });
        break;
      default:
        Rx.Observable.fromPromise(snap.ref.child(keys[0]).child('random').set(random))
          .subscribe(function () {
            console.log('changed');
          });
        break;
    }
  });

Rx.Observable.fromEvent(ref, 'child_added').subscribe(function (snap) {
  console.log('child_added', snap.key);
});

Rx.Observable.fromEvent(ref, 'child_changed').subscribe(function (snap) {
  console.log('child_changed', snap.key);
});

Rx.Observable.fromEvent(ref, 'child_removed').subscribe(function (snap) {
  console.log('child_removed', snap.key);
});

// Rx.Observable.fromEvent(ref, 'value').subscribe(function(snap) {
//   console.log('value', snap.key, snap.val());
// });