firebase in realtime

gistfile1.js

var firebase = Meteor.npmRequire("firebase");

var values = new Mongo.Collection("values");
var databaseName = 'values/';

firebase.initializeApp({
   databaseURL : "https://xxxx.firebaseio.com/",
   serviceAccount : "/home/kkm/firebase/server/serviceAccountCredentials.json"
});

//Mongo RESET
values.remove({});

//DB Init
var ref = firebase.database().ref(databaseName);

//Firebase Incoming Events
//FIREBASE ADDED
ref.orderByChild("ts").on("child_added", function(snapshot) {
 console.log("firebase - added:", snapshot.val())
 Fiber(function() {
   try {
     values.insert(snapshot.val());
   } catch(err) {
     console.log("Already added:", snapshot.val()._id);
   }
 }).run();
}, function(errorObject) {
 console.log("The read failed: " + errorObject.code);
});

//FIREBASE REMOVE
ref.on("child_removed", function(snapshot) {
 console.log("firebase - removed:", snapshot.val())
 Fiber(function() {
     values.remove(snapshot.val());
 }).run();
});

//FIREBASE changed
ref.on("child_changed", function(snapshot) {
 console.log("firebase - changed:", snapshot.val())
 Fiber(function() {
     values.update(snapshot.val()._id, {$set : snapshot.val()});
   }
 }).run();
});


//Meteor Method with firebase and Future
var Future = Npm.require('fibers/future');
Meteor.methods({
  "getDataFirebase" : function(id) {
       var future = new Future();
       var ref = firebase.database().ref(databaseName + id);
       ref.once("value", function(snapshot) {
       return future.return(snapshot.val()); //Wartet und endlich Wert zurück.
    }, function(errorObject) {
       console.log("The read failed: " + errorObject.code);
    });
    return future.wait();
  }
});

INSERT:
var rnd = Random.id();
var ref = firebase.database().ref(databaseName + rnd);
ref.set({ts : +(new Date), data : value, _id : rnd});