node-server.js

var http = require("http"),
  url = require("url"),
  path = require("path"),
  fs = require("fs");
port = process.argv[2] || 8888;

http
  .createServer(function(request, response) {
    var uri = url.parse(request.url).pathname,
      filename = path.join(process.cwd(), "docs", uri);

    var extname = path.extname(filename);
    var contentType = "text/html";
    switch (extname) {
      case ".js":
        contentType = "text/javascript";
        break;
      case ".css":
        contentType = "text/css";
        break;
      case ".ico":
        contentType = "image/x-icon";
        break;
      case ".svg":
        contentType = "image/svg+xml";
        break;
    }

    fs.exists(filename, function(exists) {
      if (!exists) {
        response.writeHead(404, { "Content-Type": "text/plain" });
        response.write("404 Not Found\n");
        response.end();
        return;
      }

      if (fs.statSync(filename).isDirectory()) filename += "/index.html";

      fs.readFile(filename, "binary", function(err, file) {
        if (err) {
          response.writeHead(500, { "Content-Type": "text/plain" });
          response.write(err + "\n");
          response.end();
          return;
        }
        response.writeHead(200, { "Content-Type": contentType });
        response.write(file, "binary");
        response.end();
      });
    });
  })
  .listen(parseInt(port, 10));

console.log("WebUI Aria2 Server is running on http://localhost:" + port);