Node http server for dev

server.js

# nodejs http server

```javascript
var http = require('http');
var path = require('path');
var url = require('url');
var fs = require('fs');
var port = 4020;

var extensions = {
    ".html": "text/html",
    ".css": "text/css",
    ".js": "application/javascript",
    ".png": "image/png",
    ".gif": "image/gif",
    ".jpg": "image/jpeg"
};

http.createServer(function (request, response) {
    var my_path = url.parse(request.url).pathname || 'index.html'; // set path to index.html if nothing is specified
    var full_path = path.join(process.cwd(), my_path);
    var ext = path.extname(my_path);
    var mime;

    if (extensions[ext]) {
        mime = extensions[ext];
    }

    fs.exists(full_path, function (exists) {
        if (!exists) {
            response.writeHeader(404, {'Content-Type': 'text/plain'});
            response.write('404 Not Found\n');
            response.end();
        }
        else {
            fs.readFile(full_path, 'binary', function (err, file) {
                if (err) {
                    response.writeHeader(500, {'Content-Type': 'text/plain'});
                    response.write(err + '\n');
                    response.end();
                }
                else {
                    var ip = request.connection.remoteAddress;
                    var ts = new Date().toLocaleString();
                    console.log(ts, '  ', ip, '  ', '200', '  ', my_path, mime);
                    response.writeHeader(200,{'Content-Type': mime});
                    response.write(file, 'binary');
                    response.end();
                }
            });
        }
    });

}).listen(port);

console.log('node server running on port: ' + port);
```