node_helper.js

/* Magic Mirror
 * Module: HH-LocalTransport
 *
 * By Georg Peters https://github.com/georg90/
 * based on a Script from Benjamin Angst http://www.beny.ch
 * MIT Licensed.
 */

const NodeHelper = require("node_helper");
const forge = require('node-forge');
const unirest = require('unirest');

module.exports = NodeHelper.create({

		start: function () {
	    this.started = false;
	  	},

			/* createSimpleToken(payload)
		 * Create authentication for custom API
		 */
			createSimpleToken: function(payload) {
					var hmac = forge.hmac.create();
			    hmac.start('sha1', this.config.customAPIToken);
			    hmac.update(forge.util.encodeUtf8(JSON.stringify(payload)));
			    var hash = hmac.digest().toHex();
			    var token = new Buffer(hash, 'hex').toString('base64');
					//console.log("token: " + token);
			    return token;
		},
	  	/* getSignature(payload)
		 * Create authentication for HVV (Geofox) API
		 * You'll need to request the access at their website. It's still in BETA!
		 */
	   getSignature: function(payload) {
		  	return new Promise((resolve) => {
				// Enable signature generating via external API, so you can share logins
				if (this.config.customAPI) {
						var token = this.createSimpleToken(payload);
					  unirest.post(this.config.customUrl)
						.headers({
				      'Content-Type': 'application/json;charset=UTF-8',
				      'auth-user': this.config.apiUser,
				      'token': token
				    })
					  .send(payload)
					  .end(function (response) {
					  if (response.error) { console.log("Error: ", response.error); }
					  else {
					  resolve(response.body);
					  }
					  });
					  }
				// Otherwise use standard solution with APIkey & user present
				else {
					var hmac = forge.hmac.create();
					hmac.start('sha1', this.config.apiKey);
					hmac.update(forge.util.encodeUtf8(JSON.stringify(payload)));
					var hash = hmac.digest().toHex();
					var sig = new Buffer(hash, 'hex').toString('base64');
					resolve(sig);
				}
				});
		},

		/* updateTimetable(transports)
		 * Calls processTrains on succesfull response.
		 */
		updateTimetable: function() {
			var url = this.config.apiBase + 'departureList' // List all departures for given station
			var self = this;
			var retry = true;
			var data = {
			  "station": {
			  "type": "STATION",
			  "id": this.config.id,
			  },
			   "time": {
			   },
			   "maxList": this.config.maximumEntries,
			   "useRealtime": this.config.useRealtime,
			   "maxTimeOffset": this.config.maxTimeOffset,
				 "version": this.config.version,
				 "useRealtime": this.config.Realtime
			};
				self.getSignature(data).then((sig) => {
		    unirest.post(url)
		    .headers({
		      'Content-Type': 'application/json;charset=UTF-8',
		      'geofox-auth-user': this.config.apiUser,
		      'geofox-auth-signature': sig
		    })
		    .send(JSON.stringify(data))
		    .end(function (r) {
		    	if (r.error) {
		    		self.updateDom(this.config.animationSpeed);
		    		//console.log(self.name + " : " + r.error);
		    		retry = false;
		    	}
		    	else {
		    		//console.log("body: ", JSON.stringify(r.body));
		    		self.processTrains(r.body);
		    	}

		    	if (retry) {
					self.scheduleUpdate((self.loaded) ? -1 : this.config.retryDelay);
				}
		    });
			});
		},

		/* processTrains(data)
		 * Uses the received data to set the various values.
		 * Keep the correct date (datetime) for later use.
		 */
		processTrains: function(data) {
			this.trains = [];
			var time = data.time.time.split(':')
			hours = time[0];
			mins = time[1];
			var datetime = new Date(this.parseDate(data.time.date));
			datetime.setHours(hours);
			datetime.setMinutes(mins);
			for (var i = 0, count = data.departures.length; i < count; i++) {

				var trains = data.departures[i];
				if (trains.timeOffset < 0) {
					continue;
				}
				var departureTime = datetime.setMinutes(datetime.getMinutes() + trains.timeOffset);
				if (trains.delay != 0 && trains.delay != undefined && trains.delay < 20) {
					delay = trains.delay;
				}
				else {
					delay = null;
				}
				this.trains.push({

					departureTimestamp: trains.timeOffset,
					delay: delay,
					name: trains.line.name,
					to: trains.line.direction

				});
			}
			this.loaded = true;
			this.sendSocketNotification("TRAINS", this.trains);
		},

		/* scheduleUpdate()
		 * Schedule next update.
		 * argument delay number - Millis econds before next update. If empty, this.config.updateInterval is used.
		 */
		scheduleUpdate: function(delay) {
			var nextLoad = this.config.updateInterval;
			if (typeof delay !== "undefined" && delay >= 0) {
				nextLoad = delay;
			}

			var self = this;
			clearTimeout(this.updateTimer);
			this.updateTimer = setTimeout(function() {
				self.updateTimetable();
			}, nextLoad);
		},

		parseDate: function(input) {
		  	var parts = input.match(/(\d+)/g);
		  	return new Date(parts[2], parts[1]-1, parts[0]);
		},

		socketNotificationReceived: function(notification, payload) {
		  const self = this;
		  if (notification === 'CONFIG' && this.started == false) {
		    this.config = payload;
		    this.started = true;
		    self.scheduleUpdate(this.config.initialLoadDelay);
		    };
		  }
});