firebase队列触发了几次，我不知道为什么

Question

我正在尝试firebase-queue示例，但是队列正在触发多次，我不明白为什么。

var Queue = require('firebase-queue');
var Firebase = require('firebase');
var rootRef = new Firebase('https://scm-queue-inspeccion.firebaseio.com/');
var randomString = require('random-string');



function toTest() {
    var obj = {
        idInspeccion: randomString(),
        placa: randomString()
    }
    rootRef.child('workers').child('inspecciones').child('queue').child('tasks').push(obj)
}

function start() {
    console.log('started');

    var queueRef = rootRef.child('workers').child('inspecciones').child('queue');


    var queue = new Queue(queueRef, function(data, progress, resolve, reject) {
        // Read and process task data
        console.log(data);

        // Do some work
        progress(50);

        // Finish the task asynchronously
        setTimeout(function() {
            resolve();
        }, 5000);
    });

}

start();
toTest()

这是我的github project