I'm trying to solve for a scenario and have a mostly working solution and was hoping you guys could help.
Problem:
We wish to hold aggregated css cache locally while retaining everything else externally through public:// to our external host.
Environment:
~ Drupal 7.22, PHP 5.4.11
~ File system: Public: sites/default/files
~ File system symlink: sites/default/files is a symlink to an external file server location
Solution (so far):
~ Created a module which adds a stream wrapper "foobar://" (works)
~ Module hook_form_alters into the Admin > File System (works)
~ The hook into Admin > File System creates the directory (works)
Where it gets hairy:
In includes/common.inc, drupal_build_css_cache and drupal_clear_css_cache both have the hardcoded css storage path of 'public://css'. I need to change this to 'foobar://css'. Neither of these have a hook.
Working solution fordrupal_build_css_cache:
Backtracking a little, I found system_element_info in system/system.module that declared the aggregate_callback. hook_element_info_alter gave me a way in.
function mymodule_element_info_alter(&$type) {
if (isset($type['styles']['#aggregate_callback'])) {
$type['styles']['#aggregate_callback'] = 'mymodule_drupal_aggregate_css';
}
}I then pulled drupal_aggregate_css into my module and changed drupal_build_css_cache to mymodule_drupal_aggregate_css
...
case 'file':
if ($group['preprocess'] && $preprocess_css) {
$css_groups[$key]['data'] = mymodule_drupal_build_css_cache($group['items']);
}
break;
...Lastly, mymodule_drupal_build_css_cache is a clone of drupal_build_css_cache with the exception of the path to the filesystem.
...
$filename = 'css_' . drupal_hash_base64($data) . '.css';
// Create the css/ within the files folder.
- $csspath = 'public://css';
+ $csspath = 'foobar://css';
$uri = $csspath . '/' . $filename;
// Create the CSS file.
file_prepare_directory($csspath, FILE_CREATE_DIRECTORY);
...That all works. Yay.
Where I'm stuck:drupal_clear_css_cache is called from more places than the above and I couldn't find an obvious way to hook it.
Any thoughts would be greatly appreciated!
