tail -f webserver version, using chunked responses (HTTP 1.1) http://goo.gl/4VuKS6

chunked.js

/**
 * tail -f webserver version, using chunked responses (HTTP 1.1)
 * slides: http://goo.gl/4VuKS6
 */
var fs = require('fs'),
    util = require('util'),
    http = require('http');

http.createServer(function (req, res) {
  fs.stat(req.url, function (err, stats) {
    var readBytes = 0,
        streamFile = function (filename, outputStream, isWatching) {
          var watchFn = function () {
            var fileToStream = fs.createReadStream(filename, { start: readBytes, encoding: 'utf8' });
            fileToStream.on('data', function (chunk) {
              readBytes += chunk.length;
              outputStream.write(chunk);
            });
            return fileToStream;
          };
          if (isWatching) {
            return watchFn;
          } else {
            return watchFn(null, filename);
          }
        };

    if (err) {
      res.statusCode = 404;
      return res.end();
    }
    if (!stats.isFile()) {
      res.statusCode = 412;
      return res.end();
    } else {
      res.statusCode = 200;
      streamFile(req.url, res)
      .on('end', function () {
        console.log('GET: ' + req.url);
        fs.watch(req.url, streamFile(req.url, res, true));
      });
    }
  });
}).listen(2610);

package.json

{
  "name": "nodejs-tail",
  "version": "0.1.0",
  "description": "a tail -f version coded in node.js",
  "main": "chunked.js",
  "repository": {
    "type": "git",
    "url": "github.com:7155518.git"
  },
  "keywords": [
    "nodejs",
    "tail",
    "chunked"
  ],
  "author": "mrgamer",
  "license": "MIT",
  "dependencies": {
    "express": "~3.4.0",
    "async": ">=0.2.0",
    "docular": "https://github.com/TopCS/docular/tarball/master"
  }
}