Finding unused images in a Rails app?

Question

I'm familiar with tools like Deadweight for finding CSS not in use in your Rails app, but does anything exist for images? I'm sitting in a project with a massive directory of assets from working with a variety of designers and I'm trying to trim the fat in this project. It's especially a pain when moving assets to our CDN.

Any thoughts?

Answer 1

It depends greatly on the code using the images. It's always possible that a filename is computed (by concatenating two values or string substitution etc) so a simply grepping by filename isn't necessarily enough.

You could try running wget (probably already installed if you've got a linux machine, otherwise http://users.ugent.be/~bpuype/wget/ ) to mirror your whole site. Do this on the same machine or network if you can, it'll crawl your whole site and grab all the images

# mirror mysite.com accepting only jpg, png and gif files
wget -A jpg,png,gif --mirror www.mysite.com

Once you've done that, you're going to have a second copy of your site's hierarchy containing any images that are actively linked to by any page reachable by crawling your site. You can then backup your source image directory, and replace it with wget's copy. Next, monitor your log files for 404's pertaining to gif/jpg/png files. Hope that helps.