cid: Image Bundler Service on Node.js
Provides a web service for stateless image bundling for mobile web applications (phones + tablets on 3g) that have designs with extensive images, such as, product catalogs. This gateway takes images, builds a JSON hash map of base64 encoded images, and throws the response back to the frontend for some awesome data uri action on image elements.
Why would I use base64 encoded images instead of using css sprites?
- You can use any way you want; however, we've found for distributed development teams spriting (PSD files) can be a huge pain in the a** when merging PSDs with interface sprites
When does base64 encoded images really provide an increased performance benefit?
- When your users are on 3G or anything slower than WiFi. We've found with tests that on Wifi there's literally no difference in performance/user experience; however, on 3G/Edge, this approach is much faster with 1 JSONP request for all the images in a hash than doing extensive image http requests
What are the down sides to using this approach? this seems like a silver bullet approach to http request reduction
- It is not a silver bullet, as you will be using base64 encoded strings, so you'll end up not using the browser's cache for images on subsequent page views. This approach really benefits mCommerce (ya, mobile commerce) sites/product catalogs/image galleries instead of productivity tools.
Any browser that supports Data URI Scheme:
- Mobile Safari
- Webkit mobile (Android)
Originally, this project was primarily focused on increasing performance on mobile web applications (for phones and tablets).
cid .configure('service', 'http://localhost:3000') //where your nodejs service is hosted .configure('callback', 'cidSwapImages') //defaulted to cidSwap .configure('lookup', 'cid-src') //css selector attribute for what you want swapped in for b64 strings .start();
npm install express (required)
npm install supervisor (optional for easier development)
- Add the ability to swap in b64 strings only when the element is in viewport
- Tests on API
- Tests on how far you could push this (200+ images??)
- Test on iPad 2 3g network speed
- Use application cache for storing images that are reused
- Enable offline use by generating a JSON file with a target url and image srcs
- query string length (long image srcs)
(The MIT License)
Copyright (c) 2011 jbueza <email@example.com>
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.