function DeferCss::defer

Same name in other branches

1. 5.0.x advagg_mod/src/Asset/DeferCss.php \Drupal\advagg_mod\Asset\DeferCss::defer()
2. 6.0.x advagg_mod/src/Asset/DeferCss.php \Drupal\advagg_mod\Asset\DeferCss::defer()
3. 8.x-3.x advagg_mod/src/Asset/DeferCss.php \Drupal\advagg_mod\Asset\DeferCss::defer()

Replace stylesheet links with preload & noscript links.

Parameters

string $content: The response content.

Return value

string Updated content.

File

advagg_mod/src/Asset/DeferCss.php, line 55

Class

DeferCss

Modify stylesheet links to defer them. May lead to Flash of unstyled content.

Namespace

Drupal\advagg_mod\Asset

Code

public function defer($content) {
    if ($this->external) {
        $pattern = '/<link rel=["\']stylesheet["\'](.*)(href="[a-zA-Z0-9\\/_\\.\\-\\?\\:]*")(.*)\\/\\>/';
    }
    else {
        $pattern = '/<link rel=["\']stylesheet["\'](.*)(href="\\/[a-zA-Z0-9][a-zA-Z0-9\\/_\\.\\-\\?]*")(.*)\\/\\>/';
    }
    $content = preg_replace_callback($pattern, [
        $this,
        'callback',
    ], $content);
    // Put JS inline if configured.
    if ($this->deferMethod === 0) {
        $path = drupal_get_path('module', 'advagg_mod') . '/js/loadCSS.js';
        if (!strpos($content, $path)) {
            $path = Crypt::hashBase64($path . $this->counter);
        }
        else {
            $path = str_replace('/', '\\/', $path);
        }
        $path = preg_quote($path, '/');
        $pattern = "/<script src=['\"]\\/(.*{$path}.*)\\?.*['\"]>/";
        $content = preg_replace_callback($pattern, [
            $this,
            'inlineScript',
        ], $content);
    }
    return $content;
}