Uri Rewriting

Default operation

Minify uses an algorithm to rewrite relative URIs in CSS output to root-relative URIs so that each link points to the same location it did in its original file.

Say your style sheet http://example.org/theme/fashion/style.css contains:

body { background: url(bg.jpg); }

When Minify serves this content (from http://example.org/min/f=theme/fashion/style.css or http://example.org/min/g=css) it re-writes the URI so the image is correctly linked:

body{background:url(/theme/fashion/bg.jpg)}

You can see the steps used to rewrite your URIs by enabling debug mode.

Disable Rewriting

You can disable the automatic rewriting by setting this in min/config.php:

$min_serveOptions['rewriteCssUris'] = false;

Manual Rewriting

You can manually rewrite relative URIs in CSS in a couple ways. The simplest is to prepend a string to each relative URI:

$min_serveOptions['rewriteCssUris'] = false;
$min_serveOptions['minifierOptions']['text/css']['prependRelativePath'] = '/css/';

Or you can run the minified output through a custom post-processor function.

Document Root Confusion

Out-of-the-box, Minify gets confused when min is placed in a subdirectory of the real document root. There's now a simple workaround for this, making min more portable.

Aliases / Symlinks / Virtual Directories

Whether you use aliases, symlinks, or virtual directories, if you make content outside of the DOC_ROOT available at public URLs, Minify may need manual configuration of the $min_symlinks option to rewrite some URIs correctly. Consider this scenario, where http://example.org/static/style.css will serve /etc/static_content/style.css:

document root	/var/www
Apache mod_alias	Alias /static /etc/static_content
...or symlink	ln -s /etc/static_content /var/www/static

In /min/config.php you'll need the following:

// map URL path to file path
$min_symlinks = array(
    '//static' => '/etc/static_content'
);

This lets Minify know during the rewriting process that an internal file path starting with /etc/static_content should be rewritten as a public URI beginning with /static.

If your alias target directory is outside of DOC_ROOT, you'll also need to explicitly allow Minify to serve files from it:

$min_serveOptions['minApp']['allowDirs'] = array(
    '//',                 // allow from the normal DOC_ROOT
    '/etc/static_content' // allow from our alias target
); 

What's my document root?

You can enable the script min/server-info.php and open http://example.org/min/server-info.php to find useful $_SERVER values. People in the Google Group might need these to help you.

It's still not working

1. Make sure you have the latest version.
2. Enable debug mode, which will show you the URI transformation process.
3. Check that $_SERVER['DOCUMENT_ROOT'] is a real directory path. If not, URI rewriting will fail. If you cannot fix this in httpd.conf, etc., use the configuration option.
4. Paste your debug mode comment block into a new post on the minify mailing list.