class CssCollectionOptimizer in Drupal 8
Same name and namespace in other branches
- 9 core/lib/Drupal/Core/Asset/CssCollectionOptimizer.php \Drupal\Core\Asset\CssCollectionOptimizer
Optimizes CSS assets.
Hierarchy
- class \Drupal\Core\Asset\CssCollectionOptimizer implements AssetCollectionOptimizerInterface
Expanded class hierarchy of CssCollectionOptimizer
1 string reference to 'CssCollectionOptimizer'
- core.services.yml in core/
core.services.yml - core/core.services.yml
1 service uses CssCollectionOptimizer
File
- core/
lib/ Drupal/ Core/ Asset/ CssCollectionOptimizer.php, line 11
Namespace
Drupal\Core\AssetView source
class CssCollectionOptimizer implements AssetCollectionOptimizerInterface {
/**
* A CSS asset grouper.
*
* @var \Drupal\Core\Asset\CssCollectionGrouper
*/
protected $grouper;
/**
* A CSS asset optimizer.
*
* @var \Drupal\Core\Asset\CssOptimizer
*/
protected $optimizer;
/**
* An asset dumper.
*
* @var \Drupal\Core\Asset\AssetDumper
*/
protected $dumper;
/**
* The state key/value store.
*
* @var \Drupal\Core\State\StateInterface
*/
protected $state;
/**
* The file system service.
*
* @var \Drupal\Core\File\FileSystemInterface
*/
protected $fileSystem;
/**
* Constructs a CssCollectionOptimizer.
*
* @param \Drupal\Core\Asset\AssetCollectionGrouperInterface $grouper
* The grouper for CSS assets.
* @param \Drupal\Core\Asset\AssetOptimizerInterface $optimizer
* The optimizer for a single CSS asset.
* @param \Drupal\Core\Asset\AssetDumperInterface $dumper
* The dumper for optimized CSS assets.
* @param \Drupal\Core\State\StateInterface $state
* The state key/value store.
* @param \Drupal\Core\File\FileSystemInterface $file_system
* The file system service.
*/
public function __construct(AssetCollectionGrouperInterface $grouper, AssetOptimizerInterface $optimizer, AssetDumperInterface $dumper, StateInterface $state, FileSystemInterface $file_system = NULL) {
$this->grouper = $grouper;
$this->optimizer = $optimizer;
$this->dumper = $dumper;
$this->state = $state;
if (!$file_system) {
@trigger_error('The file_system service must be passed to CssCollectionOptimizer::__construct(), it is required before Drupal 9.0.0. See https://www.drupal.org/node/3006851.', E_USER_DEPRECATED);
$file_system = \Drupal::service('file_system');
}
$this->fileSystem = $file_system;
}
/**
* {@inheritdoc}
*
* The cache file name is retrieved on a page load via a lookup variable that
* contains an associative array. The array key is the hash of the file names
* in $css while the value is the cache file name. The cache file is generated
* in two cases. First, if there is no file name value for the key, which will
* happen if a new file name has been added to $css or after the lookup
* variable is emptied to force a rebuild of the cache. Second, the cache file
* is generated if it is missing on disk. Old cache files are not deleted
* immediately when the lookup variable is emptied, but are deleted after a
* configurable period (@code system.performance.stale_file_threshold @endcode)
* to ensure that files referenced by a cached page will still be available.
*/
public function optimize(array $css_assets) {
// Group the assets.
$css_groups = $this->grouper
->group($css_assets);
// Now optimize (concatenate + minify) and dump each asset group, unless
// that was already done, in which case it should appear in
// drupal_css_cache_files.
// Drupal contrib can override this default CSS aggregator to keep the same
// grouping, optimizing and dumping, but change the strategy that is used to
// determine when the aggregate should be rebuilt (e.g. mtime, HTTPS …).
$map = $this->state
->get('drupal_css_cache_files') ?: [];
$css_assets = [];
foreach ($css_groups as $order => $css_group) {
// We have to return a single asset, not a group of assets. It is now up
// to one of the pieces of code in the switch statement below to set the
// 'data' property to the appropriate value.
$css_assets[$order] = $css_group;
unset($css_assets[$order]['items']);
switch ($css_group['type']) {
case 'file':
// No preprocessing, single CSS asset: just use the existing URI.
if (!$css_group['preprocess']) {
$uri = $css_group['items'][0]['data'];
$css_assets[$order]['data'] = $uri;
}
else {
$key = $this
->generateHash($css_group);
$uri = '';
if (isset($map[$key])) {
$uri = $map[$key];
}
if (empty($uri) || !file_exists($uri)) {
// Optimize each asset within the group.
$data = '';
foreach ($css_group['items'] as $css_asset) {
$data .= $this->optimizer
->optimize($css_asset);
}
// Per the W3C specification at
// http://www.w3.org/TR/REC-CSS2/cascade.html#at-import, @import
// rules must precede any other style, so we move those to the
// top.
$regexp = '/@import[^;]+;/i';
preg_match_all($regexp, $data, $matches);
$data = preg_replace($regexp, '', $data);
$data = implode('', $matches[0]) . $data;
// Dump the optimized CSS for this group into an aggregate file.
$uri = $this->dumper
->dump($data, 'css');
// Set the URI for this group's aggregate file.
$css_assets[$order]['data'] = $uri;
// Persist the URI for this aggregate file.
$map[$key] = $uri;
$this->state
->set('drupal_css_cache_files', $map);
}
else {
// Use the persisted URI for the optimized CSS file.
$css_assets[$order]['data'] = $uri;
}
$css_assets[$order]['preprocessed'] = TRUE;
}
break;
case 'external':
// We don't do any aggregation and hence also no caching for external
// CSS assets.
$uri = $css_group['items'][0]['data'];
$css_assets[$order]['data'] = $uri;
break;
}
}
return $css_assets;
}
/**
* Generate a hash for a given group of CSS assets.
*
* @param array $css_group
* A group of CSS assets.
*
* @return string
* A hash to uniquely identify the given group of CSS assets.
*/
protected function generateHash(array $css_group) {
$css_data = [];
foreach ($css_group['items'] as $css_file) {
$css_data[] = $css_file['data'];
}
return hash('sha256', serialize($css_data));
}
/**
* {@inheritdoc}
*/
public function getAll() {
return $this->state
->get('drupal_css_cache_files');
}
/**
* {@inheritdoc}
*/
public function deleteAll() {
$this->state
->delete('drupal_css_cache_files');
$delete_stale = function ($uri) {
// Default stale file threshold is 30 days.
if (REQUEST_TIME - filemtime($uri) > \Drupal::config('system.performance')
->get('stale_file_threshold')) {
$this->fileSystem
->delete($uri);
}
};
if (is_dir('public://css')) {
$this->fileSystem
->scanDirectory('public://css', '/.*/', [
'callback' => $delete_stale,
]);
}
}
}
Members
Name | Modifiers | Type | Description | Overrides |
---|---|---|---|---|
CssCollectionOptimizer:: |
protected | property | An asset dumper. | |
CssCollectionOptimizer:: |
protected | property | The file system service. | |
CssCollectionOptimizer:: |
protected | property | A CSS asset grouper. | |
CssCollectionOptimizer:: |
protected | property | A CSS asset optimizer. | |
CssCollectionOptimizer:: |
protected | property | The state key/value store. | |
CssCollectionOptimizer:: |
public | function |
Deletes all optimized asset collections assets. Overrides AssetCollectionOptimizerInterface:: |
|
CssCollectionOptimizer:: |
protected | function | Generate a hash for a given group of CSS assets. | |
CssCollectionOptimizer:: |
public | function |
Returns all optimized asset collections assets. Overrides AssetCollectionOptimizerInterface:: |
|
CssCollectionOptimizer:: |
public | function |
The cache file name is retrieved on a page load via a lookup variable that
contains an associative array. The array key is the hash of the file names
in $css while the value is the cache file name. The cache file is generated
in two cases. First, if… Overrides AssetCollectionOptimizerInterface:: |
|
CssCollectionOptimizer:: |
public | function | Constructs a CssCollectionOptimizer. |