Node.js: Gzip compression?

Question

Am I wrong in finding that Node.js does no gzip compression and there are no modules out there to perform gzip compression? How can anyone use a web server that has no compression? What am I missing here? Should I try to—gasp—port the algorithm to JavaScript for server-side use?

Answer 1

Node v0.6.x has a stable zlib module in core now - there are some examples on how to use it server-side in the docs too.

An example (taken from the docs):

// server example
// Running a gzip operation on every request is quite expensive.
// It would be much more efficient to cache the compressed buffer.
var zlib = require('zlib');
var http = require('http');
var fs = require('fs');
http.createServer(function(request, response) {
  var raw = fs.createReadStream('index.html');
  var acceptEncoding = request.headers['accept-encoding'];
  if (!acceptEncoding) {
    acceptEncoding = '';
  }

  // Note: this is not a conformant accept-encoding parser.
  // See http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.3
  if (acceptEncoding.match(/\bdeflate\b/)) {
    response.writeHead(200, { 'content-encoding': 'deflate' });
    raw.pipe(zlib.createDeflate()).pipe(response);
  } else if (acceptEncoding.match(/\bgzip\b/)) {
    response.writeHead(200, { 'content-encoding': 'gzip' });
    raw.pipe(zlib.createGzip()).pipe(response);
  } else {
    response.writeHead(200, {});
    raw.pipe(response);
  }
}).listen(1337);

Answer 2

While as others have right pointed out using a front end webserver such as nginx can handle this implicitly, another option, is to use nodejitsu's excellent node-http-proxy to serve up your assets.

eg:

httpProxy.createServer(
 require('connect-gzip').gzip(),
 9000, 'localhost'
).listen(8000);

This example demonstrates support for gzip compression through the use of connect middleware module: connect-gzip.

Answer 3

There are multiple Gzip middlewares for Express, KOA and others. For example: https://www.npmjs.com/package/express-static-gzip

However, Node is awfully bad at doing CPU intensive tasks like gzipping, SSL termination, etc. Instead, use a ‘real’ middleware services like nginx or HAproxy, see bullet 3 here: http://goldbergyoni.com/checklist-best-practice-of-node-js-in-production/

Answer 4

It's been a few good days with node, and you're right to say that you can't create a webserver without gzip.

There are quite a lot options given on the modules page on the Node.js Wiki. I tried out most of them, but this is the one which I'm finally using -

https://github.com/donnerjack13589/node.gzip

v1.0 is also out and it has been quite stable so far.

Answer 5

Use gzip compression

Gzip compressing can greatly decrease the size of the response body and hence increase the speed of a web app. Use the compression middleware for gzip compression in your Express app. For example:

var compression = require('compression');
var express = require('express')
var app = express()
app.use(compression())

Answer 6

Even if you're not using express, you can still use their middleware. The compression module is what I'm using:

var http = require('http')
var fs = require('fs')
var compress = require("compression")
http.createServer(function(request, response) {
  var noop = function(){}, useDefaultOptions = {}
  compress(useDefaultOptions)(request,response,noop) // mutates the response object

  response.writeHead(200)
  fs.createReadStream('index.html').pipe(response)
}).listen(1337)