const http = require('http') const url = require('url') const fs = require('fs') const ws = require('ws') const redis = require('redis') const mime = require('mime') const XMLHttpRequest = require("xmlhttprequest").XMLHttpRequest const host = 'http://127.0.0.1:8080/' //redis client const redis_cli = redis.createClient() redis_cli.on("error", function (error) { console.error(error) }) const outpath = ['sym', ''] //HTTP server http.createServer(function (req, res) { const q = url.parse(req.url, true); let filename = "./public" + q.pathname; if (filename === "./public/") filename = "./public/index.html"; let file_type = mime.getType(filename) //q.pathname.split("/", 2)[1] === "sym" || ) if (function valid_path(){// for (let i = 0; i < outpath.length; i++) if (q.pathname.split("/", 2)[1] === outpath[i]) return true return false }() === true){ fs.readFile(filename, function(err, data) { if (err) { res.writeHead(404, {'Content-Type': file_type}); return res.end("404 Not Found"); } res.writeHead(200, {'Content-Type': file_type}); res.write(data); return res.end(); }) }else{ redis_cli.hget("surl;"+q.pathname.split("/", 2)[1], "url", function(err, obj) { if(err) console.log(err); if(obj){ res.writeHead(302, {'Location': obj}); return res.end(); }else{ res.writeHead(404, {'Content-Type': file_type}); return res.end("404 this short-url does not exist :/"); } }); } }).listen(8080); //WS server const wss = new ws.Server({ port: 8081, perMessageDeflate: { zlibDeflateOptions: { // See zlib defaults. chunkSize: 1024, memLevel: 7, level: 3 }, zlibInflateOptions: { chunkSize: 10 * 1024 }, // Other options settable: clientNoContextTakeover: true, // Defaults to negotiated value. serverNoContextTakeover: true, // Defaults to negotiated value. serverMaxWindowBits: 10, // Defaults to negotiated value. // Below options specified as default values. concurrencyLimit: 10, // Limits zlib concurrency for perf. threshold: 1024 // Size (in bytes) below which messages // should not be compressed. } }); //WS handler wss.on('connection', ws => { ws.on('message', message => { console.log(`Received message => ${message}`) let msg = `${message}`.split(";", 2) if (msg[0] === 'long_url') { if (msg[1] === '') ws.send('error;url is empty') else if (msg[1].length > 2000) ws.send('error;your url is too long') else{ let xhr = new XMLHttpRequest(); console.log(msg[1]) xhr.open('GET', msg[1], true); xhr.timeout = 2000; xhr.ontimeout = function(e) {ws.send('error;url timed out')} xhr.onreadystatechange = function() { if (xhr.readyState === 4) { switch(xhr.status) { case 200: let ran_key = get_key(8) //write to redis redis_cli.hmset("surl;"+ran_key, "url", msg[1], "time", Date.now()) ws.send('surl;'+host+ran_key) console.log('key;'+ran_key) break; case 301: ws.send('error;the url is redirecting (301)');break; case 302: ws.send('error;the url is redirecting (302)');break; case 303: ws.send('error;the url is redirecting (303)');break; case 404: ws.send('error;site does not exist (404)');break; case 502: ws.send('error;remote server error (502)');break; case 500: ws.send('error;remote server error (500)');break; case 503: ws.send('error;remote server error (503)');break; default: ws.send('error;no valid url');break; } } } xhr.send(); } } }) ws.send('websocket connected') }) //random key const forbidden_array = ['sym', 'admin', 'stats'] function get_key(length) { let forbidden = false; let output = '' let characters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789' do{ for (let i = 0; i < length; i++ ) output += characters.charAt(Math.floor(Math.random() * characters.length)) for (let i = 0; i < forbidden_array.length; i++) if (output === forbidden_array[i]) forbidden = true } while (forbidden) return output }