LoggingWebServer.js

var http = require('http');
var fs = require('fs');

var optimist = require('optimist')
  .usage('Simple web server to log incoming requests.\n\nUsage: $0 [options]')
  .options({
    file: {
      alias: 'f',
      describe: 'Path of file to log to. Server will log to stdout if no file specified.'
    },
    port: {
      alias: 'p',
      describe: 'Port to listen to. Defaults to 8000.',
      type: 'number',
      default: 8000
    },
    help: {
      describe: 'Display help message',
      type: 'boolean'
    }
  });

var argv = optimist.argv;

if (argv.help) {
  optimist.showHelp(console.log);
  process.exit();
}

if (argv.file) {
  try {  	
    argv.output_file = fs.openSync(argv.file, "a+");
  }
  catch (e) {
    console.log('Error opening output file %s: %s', argv.file, e.message);
    process.exit;
  }
}


http.createServer(function (req, res) {
  var body = "";
  req.on('data', function (chunk) {
    body += chunk;
  });
  req.on('end', function () {
    var timestamp = new Date().toISOString();
    if (argv.output_file) {
      var logline = timestamp + ': ' + req.method + ' ' + req.url + ' ' + body + '\n';
      fs.writeSync(argv.output_file, logline);
    } else {
      console.log('%s: %s %s %s', timestamp, req.method, req.url, body);
    }

    res.writeHead(200);
    res.end();
  });
}).listen(argv.port, '0.0.0.0');
console.log('Server running at http://0.0.0.0:%d/', argv.port);