Stap 3: Het node.js deel
Met behulp van de terminal verbinding, maken de volgende node.js bestand:
web_button.js (download het bijgevoegde bestand, code was waarschijnlijk gebroken na het plakken hier)
/Tmp/arduino.txt bijgewerkt wanneer een gebruiker een opdracht vanuit de webinterface verzendt.
/* web_button.js Part of "Intel IoT Edison web controlled LED demo" Copyright 2014 Pavlos Iliopoulos, techprolet.com This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. */ var http = require('http'); var url = require('url'); var fs = require('fs'); var arduinoFileName = "/tmp/arduino.txt"; function sendResponse(ledOn, remoteIP, response) { if (remoteIP != null){ console.log('\nRequest to switch LED ' + (ledOn?'On':'Off')); console.log('from ' + remoteIP); var fileStream = fs.createWriteStream(arduinoFileName); fileStream.write(ledOn + "\n" + remoteIP + "\nOK\n"); fileStream.end(); response.writeHead(302, { 'Location': '/' }); response.end(); } else { response.writeHead(200, { 'Content-Type': 'text/html' }); response.write('<!DOCTYPE html><html lang="en"><head>'); response.write('<meta charset="utf-8">'); response.write('<meta http-equiv="refresh" content="30" />'); response.write('<title>LED switch</title>'); if (!ledOn) { response.write ('<style>body{background-color:black;color:white;}</style>'); } response.write('</head>'); response.write('<body><h1>LED is now '+(ledOn?'On':'Off')); response.write('</h1>'); if (ledOn){ response.write('<a href="/off">Switch off!</a>'); } else { response.write('<a href="/on">Switch on!</a>'); } response.write('</body></html>'); response.end(); } } function processRequest(request, response) { "use strict"; var pathName = url.parse(request.url).pathname; var remoteIP = request.headers['X-Forwarded-For'] == undefined?request.connection.remoteAddress:request.headers['X-Forwarded-For']; if (pathName == "/on") { sendResponse (true, remoteIP, response); } else if (pathName == "/off") { sendResponse (false, remoteIP, response); } else if (pathName == "/") { fs.exists(arduinoFileName, function (exists) { if (exists){ fs.readFile(arduinoFileName, function(err,data){ if (!err){ console.log('\nStored data:\n' + data); var storedData = data.toString().split("\n"); sendResponse ((storedData[0] == "true"), null, response); }else{ console.log(err); } }); } else { sendResponse (false, null, response); } }); } else { response.end(); } } http.createServer(processRequest).listen(8080); console.log("Server running at port 8080"); Voer het script met de volgende opdracht:
# knooppunt web_button.js
Het web is dan bereikbaar op http://youredisonaddress:8080 /
That's it! Pret met uw web heb gecontroleerde Edison!
