bitbus.js

// requiring just allows me to use functionality or code from an external source
// bitbar is a JavaScript module I'm using to make the menubar
// i just structure an array properly and pass it to bitbar and it makes the application
const bitbar = require('bitbar');
// superagent is a http request library
// basically it allows me to easily make a call to the OneBusAway API
// im setting it equal to "request", and you can see it later
const request = require('superagent');
// moment is a small library that parses crazy time formats into human readable ones
// eg: 1467317117000 (unix epoch time in milliseconds) to '15 minutes away'
const moment = require('moment');
// this is an API key I got from the devs at OneBusAway
// it's in a different directory on my copmuter (./src/API_KEY) and NOT on Github so no one can take it
// if there is none, i use the 'TEST' that still works but is limited to less requests
const busAPIKey = require('./src/API_KEY.js') || 'TEST';

// this is the number of the bus stop in front of my work
var busStop = 18610;
// this is the URL to the OneBusAway url
var busAPI = `http://api.pugetsound.onebusaway.org/api/where/arrivals-and-departures-for-stop/1_${busStop}.json?key=${busAPIKey}`;

// request is superagent, just assigned to a variable so i can use it more easily
// init request
request
// GET (shoot a request to) the API url I set in a variable above
.get(busAPI)
// one you got it (end)..
.end(function(err, res) {
  //  ..parse the response (res) from JSON (which is the format I get it in) to a JavaScript object
  var response = JSON.parse(res.text);

  // dig into the response to the key we want (all arrivals and departures from my stop)
  var trips = response.data.entry.arrivalsAndDepartures
    // filter out just the arrivals for my bus number (32)
    .filter(function(trip) {
      return trip.routeShortName == '32';
    })
    // get the scheduled and predicted arrival times for the busses that were filtered above
    .map(function(trip) {
      var newTrip = {};
      newTrip.scheduledArrival = moment(trip.scheduledArrivalTime).fromNow(); 
      newTrip.predictedArrival = moment(trip.predictedArrivalTime).fromNow();

      return newTrip;
    });

  // menu is the array I will send to bitbar at the end to create my menubar applet
  var menu = [];
  // the first arrival is the text you see in the menu without opening it
  menu.push({
    // add a bus emoji, then the predicted arrival time
    // if there is no predicted time, use the scheduled time
    text: ':bus: ' + trips[0].predictedArrival || trips[0].scheduledArrival,
    // set the color to white if it's predicted, otherwise make it red
    // this is because a scheduled bus might not actually be an accurate time
    color: trips[0].predictedArrival ? 'white' : 'red'
  });

  // this is for the rest of the arrivals after the most recent one
  // for each arrival AFTER the first one..
  trips.slice(1).forEach(function(trip) {
    // ..add a point_right emoji, and then the predicted or scheduled time like above
    menu.push({
      text: ':point_right: ' + trip.predictedArrival || trip.scheduledArrival,
      color: trip.predictedArrival ? 'white' : 'red'
    })
  });

  // get the big menu array i just created and pass it to bitbar to make the menubar app!
  bitbar(menu);
});