Queue static cache purge requests

README.md

@@ -225,4 +225,4 @@ Most configuration (to Craft and the extension itself) is handled directly by Cl
 
 The `StaticCache::EVENT_BEFORE_PURGE` event fires immediately before each tag purge, including the collected end-of-request batch. Listeners can modify its `tags` or cancel the purge.
 
-When a saved element purge proceeds, its non-null site URL is included in tag-based gateway API requests as the optional `fetchUrls` field. URLs are deduplicated, and the gateway asynchronously fetches them after a successful purge to repopulate the cache. Drafts, revisions, deletions, and canceled purges do not send URLs.
+Web requests dispatch tag purges to the gateway with a Craft queue job. When a saved element purge proceeds, its non-null site URL is included as the optional `fetchUrls` field. URLs are deduplicated, and the gateway asynchronously fetches them after a successful purge to repopulate the cache. Drafts, revisions, deletions, and canceled purges do not enqueue URLs. Non-web purges execute the same job immediately.

src/HeaderEnum.php

@@ -5,7 +5,6 @@
 enum HeaderEnum: string
 {
     case CACHE_TAG = 'Cache-Tag';
-    case CACHE_PURGE_TAG = 'Cache-Purge-Tag';
     case CACHE_PURGE_PREFIX = 'Cache-Purge-Prefix';
     case CACHE_CONTROL = 'Cache-Control';
     case CDN_CACHE_CONTROL = 'CDN-Cache-Control';

src/Helper.php

@@ -36,36 +36,24 @@ public static function makeGatewayApiRequest(iterable $headers): ResponseInterfa
             ->values()
             ->all();
 
-        $tags = [];
         $prefixes = [];
 
         foreach ($headers as $name => $value) {
-            if (HeaderEnum::CACHE_PURGE_TAG->matches((string) $name)) {
-                $tags = $normalizeHeaderValue($value);
-
-                if (!empty($tags)) {
-                    break;
-                }
-
-                continue;
-            }
-
             if (HeaderEnum::CACHE_PURGE_PREFIX->matches((string) $name)) {
                 $prefixes = $normalizeHeaderValue($value);
+                break;
             }
         }
 
-        if (empty($tags) && empty($prefixes)) {
-            throw new Exception('Gateway API requests require a supported purge header.');
+        if (empty($prefixes)) {
+            throw new Exception('Gateway API requests require a Cache-Purge-Prefix header.');
         }
 
         return self::createGatewayApiClient()->request(
             'POST',
             'cache/purge',
             [
-                RequestOptions::JSON => !empty($tags)
-                    ? ['tags' => $tags]
-                    : ['prefixes' => $prefixes],
+                RequestOptions::JSON => ['prefixes' => $prefixes],
             ],
         );
     }

src/StaticCache.php

@@ -5,6 +5,7 @@
 use Craft;
 use craft\base\ElementInterface;
 use craft\cloud\events\PurgeEvent;
+use craft\cloud\queue\PurgeStaticCacheJob;
 use craft\events\ElementEvent;
 use craft\events\InvalidateElementCachesEvent;
 use craft\events\RegisterCacheOptionsEvent;
@@ -24,7 +25,7 @@
 use yii\caching\TagDependency;
 
 /**
- * Static Cache tags can appear in the `Cache-Tag` and `Cache-Purge-Tag` headers.
+ * Static Cache tags can appear in the `Cache-Tag` header.
  * The values are comma-separated and can be in several formats:
  *
  * - Added by the gateway:
@@ -348,14 +349,6 @@ private function sendPurgeTagsRequest(
         Collection $tags,
         ?Collection $fetchUrls = null,
     ): void {
-        $response = Craft::$app->getResponse();
-        $isWebResponse = $response instanceof \craft\web\Response;
-
-        // Add any existing tags from the response headers
-        if ($isWebResponse) {
-            $tags->push(...$this->parseCacheTagsFromHeader(HeaderEnum::CACHE_PURGE_TAG->value));
-        }
-
         $tags = $this->normalizeCacheTags(...$tags);
 
         if ($tags->isEmpty()) {
@@ -367,10 +360,6 @@ private function sendPurgeTagsRequest(
         ]);
         $this->trigger(self::EVENT_BEFORE_PURGE, $event);
 
-        if ($isWebResponse) {
-            $response->getHeaders()->remove(HeaderEnum::CACHE_PURGE_TAG->value);
-        }
-
         $overflowTag = $this->overflowTag();
         $tags = $event->isValid
             ? $this->normalizeCacheTags(...$event->tags)
@@ -383,53 +372,18 @@ private function sendPurgeTagsRequest(
         }
 
         $fetchUrls ??= Collection::make();
-        $sendApiRequest = !$isWebResponse || $fetchUrls->isNotEmpty();
-
-        if (!$sendApiRequest) {
-            $tags = $this->truncateCacheTagsForHeader($tags);
-
-            Module::info('Purging tags', [
-                'tags' => $tags,
-            ]);
-
-            $this->setCacheTagHeader(
-                HeaderEnum::CACHE_PURGE_TAG->value,
-                $tags,
-            );
-
-            return;
-        }
-
-        Module::info('Purging tags', [
-            'tags' => $tags,
-            'fetchUrls' => $fetchUrls,
-        ]);
-
-        $payload = [
+        $job = new PurgeStaticCacheJob([
             'tags' => $tags->map(fn(StaticCacheTag $tag) => (string) $tag)->values()->all(),
-        ];
-
-        if ($fetchUrls->isNotEmpty()) {
-            $payload['fetchUrls'] = $fetchUrls
+            'fetchUrls' => $fetchUrls
                 ->unique()
                 ->values()
-                ->all();
-        }
-
-        try {
-            Helper::createGatewayApiClient()->request('POST', 'cache/purge', [
-                RequestOptions::JSON => $payload,
-                RequestOptions::TIMEOUT => 40,
-            ]);
-        } catch (\Throwable $e) {
-            if ($isWebResponse) {
-                $this->setCacheTagHeader(
-                    HeaderEnum::CACHE_PURGE_TAG->value,
-                    $this->truncateCacheTagsForHeader($tags),
-                );
-            }
+                ->all(),
+        ]);
 
-            throw $e;
+        if (Craft::$app->getResponse() instanceof \craft\web\Response) {
+            Craft::$app->getQueue()->push($job);
+        } else {
+            $job->execute(Craft::$app->getQueue());
         }
     }
 

src/queue/PurgeStaticCacheJob.php

@@ -0,0 +1,47 @@
+<?php
+
+namespace craft\cloud\queue;
+
+use craft\cloud\Helper;
+use craft\cloud\Module;
+use craft\i18n\Translation;
+use craft\queue\BaseJob;
+use GuzzleHttp\RequestOptions;
+
+class PurgeStaticCacheJob extends BaseJob
+{
+    /**
+     * @var string[]
+     */
+    public array $tags = [];
+
+    /**
+     * @var string[]
+     */
+    public array $fetchUrls = [];
+
+    protected function defaultDescription(): ?string
+    {
+        return Translation::prep('app', 'Purging static cache');
+    }
+
+    public function execute($queue): void
+    {
+        Module::info('Purging tags', [
+            'tags' => $this->tags,
+            'fetchUrls' => $this->fetchUrls,
+        ]);
+
+        $payload = [
+            'tags' => $this->tags,
+        ];
+
+        if ($this->fetchUrls !== []) {
+            $payload['fetchUrls'] = $this->fetchUrls;
+        }
+
+        Helper::createGatewayApiClient()->request('POST', 'cache/purge', [
+            RequestOptions::JSON => $payload,
+        ]);
+    }
+}