express-cdn 0.0.3
Node.js module for delivering optimized, minified, mangled, gzipped, and CDN-hosted assets in Express using S3 and CloudFront.
Follow @niftylettuce on Twitter for updates.
Currently supports express
version 2.x (not 3.x compatible yet).
Like this module? You should also check out node-email-templates!
Features
- Built-in optimization of images in production mode using OptiPNG and JPEGTran.
- Supports Sass, LESS, and Stylus using respective stylesheet compilers.
- JavaScript assets are mangled and minified using UglifyJS.
- Automatic detection of asset changes and will only upload changed assets to S3 in production mode.
- Utilizes cachebusting, which is inspired by express-cachebuster and h5bp.
- All assets are compressed using zlib into a gzip buffer for S3 uploading with
Content-Encoding
header set to gzip
. - Embed multiple assets as a single
<script>
or <link>
tag using the built-in dynamic view helper. - Loads and processes assets per view (allowing you to minimize client HTTP requests).
- Combine commonly used assets together using a simple array argument.
- Uploads changed assets automatically and asynchronously to Amazon S3 (only in production mode) using knox.
Lazy Web Requests
- Automatic parsing of
CDN(...)
in stylesheets and scripts. - Add options to pick CDN network (e.g. MaxCDN vs. Amazon vs. Rackspace)
- Add tests for all asset types.
- Modularization of
/lib/main.js
please! - Support Express 3.x.x+ and utilize async with view helper.
- Convert from
fs.statSync
to fs.stat
with callback for image assets modified timestamp hack. - Investigate why Chrome Tools Audit returns leverage proxy cookieless jargon.
How does it work?
When the server is first started, the module returns a view helper depending on
the server environment (production or development). It also recursively
searches through your viewsDir
for any views containing instances of the
CDN(...)
view helper. After parsing each instance and removing duplicates,
it will use your S3 credentials to upload a new copy of the production-quality
assets. Enjoy :).
Environment Differences
Development Mode:
Assets are untouched, cachebusted, and delivered as typical local files for rapid development.
Production Mode:
Assets are optimized, minified, mangled, gzipped, delivered by Amazon CloudFront CDN, and hosted from Amazon S3.
CDN Setup Instructions
- Visit https://console.aws.amazon.com/s3/home and click Create Bucket.
- Bucket Name:
bucket-name
- Region:
US Standard
- Upload index.html to your new bucket (this will serve as a placeholder in case someone accesses http://cdn.your-site.com/).
- Select
index.html
in the Objects and Folders view from your S3 console and click Actions → Make Public. - Visit https://console.aws.amazon.com/cloudfront/home and click Create Distribution.
- Choose an origin:
- Origin Domain Name:
bucket-name.s3.amazonaws.com
- Origin ID:
S3-bucket-name
- Create default behavior:
- Path Pattern:
Default (*)
- Origin:
S3-bucket-name
- Viewer Protocol Policy:
HTTP and HTTPS
- Object Caching:
Use Origin Cache Headers
- Forward Query String:
No (Improves Caching)
- Distribution details:
- Alternate Domain Names (CNAMEs):
cdn.your-domain.com
- Default Root Object:
index.html
- Logging:
Off
- Comments:
Created with express-cdn by @niftylettuce.
- Distribution State:
Enabled
- Copy the generated Domain Name (e.g.
xyz.cloudfront.net
) to your clipboard. - Log in to your-domain.com's DNS manager, add a new CNAME "hostname" of
cdn
, and paste the contents of your clipboard as the the "alias" or "points to" value. - After the DNS change propagates, you can test your new CDN by visiting http://cdn.your-domain.com (the
index.html
file should get displayed).
Installation
sudo apt-get install optipng libjpeg-progs
npm install express-cdn
Usage
Server
var express = require('express')
, path = require('path')
, app = express.createServer();
var options = {
publicDir : path.join(__dirname, 'public')
, viewsDir : path.join(__dirname, 'views')
, domain : 'cdn.your-domain.com'
, bucket : 'bucket-name'
, key : 'amazon-s3-key'
, secret : 'amazon-s3-secret'
, hostname : 'localhost'
, port : 1337
, ssl : false
, production : true
};
var CDN = require('express-cdn')(app, options);
app.configure(function() {
app.set('view engine', 'jade');
app.set('view options', { layout: false, pretty: true });
app.enable('view cache');
app.use(express.bodyParser());
app.use(express.static(path.join(__dirname, 'public')));
});
app.dynamicHelpers({ CDN: CDN });
app.get('/', function(req, res, next) {
res.render('basic');
return;
});
console.log("Server started: http://localhost:1337");
app.listen(1337);
View Engine
Jade
// #1 - Load an image
!= CDN('/img/sprite.png')
// #2 - Load an image with a custom tag attribute
!= CDN('/img/sprite.png', { alt: 'Sprite' })
// #3 - Load a script
!= CDN('/js/script.js')
// #4 - Load a script with a custom tag attribute
!= CDN('/js/script.js', { 'data-message': 'Hello' })
// #5 - Load and concat two scripts
!= CDN([ '/js/plugins.js', '/js/script.js' ])
// #6 - Load and concat two scripts with custom tag attributes
!= CDN([ '/js/plugins.js', '/js/script.js' ], { 'data-message': 'Hello' })
// #7 - Load a stylesheet
!= CDN('/css/style.css')
// #8 - Load and concat two stylesheets
!= CDN([ '/css/style.css', '/css/extra.css' ])
EJS
<!-- #1 - Load an image -->
<%- CDN('/img/sprite.png') %>
<!-- #2 - Load an image with a custom tag attribute -->
<%- CDN('/img/sprite.png', { alt: 'Sprite' }) %>
<!-- #3 - Load a script -->
<%- CDN('/js/script.js') %>
<!-- #4 - Load a script with a custom tag attribute -->
<%- CDN('/js/script.js', { 'data-message': 'Hello' }) %>
<!-- #5 - Load and concat two scripts -->
<%- CDN([ '/js/plugins.js', '/js/script.js' ]) %>
<!-- #6 - Load and concat two scripts with custom tag attributes -->
<%- CDN([ '/js/plugins.js', '/js/script.js' ], { 'data-message': 'Hello' }) %>
<!-- #7 - Load a stylesheet -->
<%- CDN('/css/style.css') %>
<!-- #8 - Load and concat two stylesheets -->
<%- CDN([ '/css/style.css', '/css/extra.css' ]) %>
Automatically Rendered HTML
Development Mode
<img src="/img/sprite.png?v=1341214029" />
<img src="/img/sprite.png?v=1341214029" alt="Sprite" />
<script src="/js/script.js?v=1341214029" type="text/javascript"></script>
<script src="/js/script.js?v=1341214029" type="text/javascript" data-message="Hello"></script>
<script src="/js/plugins.js?v=1341214029" type="text/javascript"></script>
<script src="/js/script.js?v=1341214029" type="text/javascript"></script>
<script src="/js/plugins.js?v=1341214029" type="text/javascript" data-message="Hello"></script>
<script src="/js/script.js?v=1341214029" type="text/javascript" data-message="Hello"></script>
<link href="/css/style.css?v=1341214029" rel="stylesheet" type="text/css" />
<link href="/css/style.css?v=1341214029" rel="stylesheet" type="text/css" />
<link href="/css/extra.css?v=1341214029" rel="stylesheet" type="text/css" />
Production Mode
The protocol will automatically change to "https" or "http" depending on the SSL option.
The module will automatically upload and detect new/modified assets based off timestamp,
as it utilizes the timestamp for version control! There is built-in magic to detect if
individual assets were changed when concatenating multiple assets together (it adds the
timestamps together and checks if the combined asset timestamp on S3 exists!).
<img src="https://cdn.your-site.com/img/sprite.1341382571.png" />
<img src="https://cdn.your-site.com/img/sprite.1341382571.png" alt="Sprite" />
<script src="https://cdn.your-site.com/js/script.1341382571.js" type="text/javascript"></script>
<script src="https://cdn.your-site.com/js/script.1341382571.js" type="text/javascript" data-message="Hello"></script>
<script src="https://cdn.your-site.com/plugins%2Bscript.1341382571.js" type="text/javascript"></script>
<script src="https://cdn.your-site.com/plugins%2Bscript.1341382571.js" type="text/javascript" data-message="Hello"></script>
<link href="https://cdn.your-site.com/css/style.1341382571.css" rel="stylesheet" type="text/css" />
<link href="https://cdn.your-site.com/style%2Bextra.1341382571.css" rel="stylesheet" type="text/css" />
Contributors
License
MIT Licensed