Version 1

[yaffs-website] / web / modules / contrib / http2_server_push / src / Asset / JsCollectionRenderer.php

diff --git a/web/modules/contrib/http2_server_push/src/Asset/JsCollectionRenderer.php b/web/modules/contrib/http2_server_push/src/Asset/JsCollectionRenderer.php
new file mode 100644 (file)
index 0000000..f9525a1
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+++ b/web/modules/contrib/http2_server_push/src/Asset/JsCollectionRenderer.php
@@ -0,0 +1,78 @@
+<?php
+
+namespace Drupal\http2_server_push\Asset;
+
+use Drupal\Core\Asset\AssetCollectionRendererInterface;
+use Symfony\Component\HttpFoundation\RequestStack;
+
+/**
+ * Decorates the JS collection renderer service, adds Server Push.
+ *
+ * @see \Drupal\Core\Asset\JsCollectionRenderer
+ * @see \Drupal\http2_server_push\Render\HtmlResponseAttachmentsProcessor
+ */
+class JsCollectionRenderer implements AssetCollectionRendererInterface {
+
+  use AssetHtmlTagRenderElementTrait;
+
+  /**
+   * The decorated JS collection renderer.
+   *
+   * @var \Drupal\Core\Asset\AssetCollectionRendererInterface
+   */
+  protected $jsCollectionRenderer;
+
+  /**
+   * The request stack.
+   *
+   * @var \Symfony\Component\HttpFoundation\RequestStack
+   */
+  protected $requestStack;
+
+  /**
+   * Constructs a JsCollectionRenderer.
+   *
+   * @param \Drupal\Core\Asset\AssetCollectionRendererInterface $js_collection_renderer
+   *   The decorated JS collection renderer.
+   * @param \Symfony\Component\HttpFoundation\RequestStack $request_stack
+   *   The request stack.
+   */
+  public function __construct(AssetCollectionRendererInterface $js_collection_renderer, RequestStack $request_stack) {
+    $this->jsCollectionRenderer = $js_collection_renderer;
+    $this->requestStack = $request_stack;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function render(array $js_assets) {
+    $elements = $this->jsCollectionRenderer->render($js_assets);
+
+    $request = $this->requestStack->getCurrentRequest();
+    $link_headers = $request->attributes->get('http2_server_push_link_headers', []);
+    foreach ($elements as &$element) {
+      if (!static::isScript($element)) {
+        continue;
+      }
+
+      // Locally served JS files that are sent to all browsers can be pushed.
+      if (isset($element['#attributes']['src']) && static::hasRootRelativeUrl($element, 'src') && static::isUnconditional($element)) {
+        $link_header_value = '<' . $element['#attributes']['src'] . '>; rel=preload; as=script';
+        $link_headers[] = $link_header_value;
+
+        // @todo When this is moved into Drupal core, consider allowing bubbling
+        // of bubbleable metadata from the return value of
+        // \Drupal\Core\Render\HtmlResponseAttachmentsProcessor::processAssetLibraries
+        // so this line of code can work, which would mean we would no longer
+        // need to use request attributes. (The problem is that a key assumption
+        // is that rendering set of asset libraries to HTML that loads CSS/JS,
+        // no further attachment bubbling happens. That's a fine assumption, but
+        // this module is the first and sole exception.)
+        //$element['#attached']['http_header'][] = ['Link', $link_header_value];
+      }
+    }
+    $request->attributes->set('http2_server_push_link_headers', $link_headers);
+    return $elements;
+  }
+
+}