refactor: extract PageCache class

system/Cache/PageCache.php

@@ -0,0 +1,130 @@
+<?php
+
+/**
+ * This file is part of CodeIgniter 4 framework.
+ *
+ * (c) CodeIgniter Foundation <[email protected]>
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace CodeIgniter\Cache;
+
+use CodeIgniter\HTTP\CLIRequest;
+use CodeIgniter\HTTP\IncomingRequest;
+use CodeIgniter\HTTP\ResponseInterface;
+use Config\Cache as CacheConfig;
+use Exception;
+
+/**
+ * Web Page Caching
+ */
+class PageCache
+{
+    /**
+     * Whether to take the URL query string into consideration when generating
+     * output cache files. Valid options are:
+     *
+     *    false      = Disabled
+     *    true       = Enabled, take all query parameters into account.
+     *                 Please be aware that this may result in numerous cache
+     *                 files generated for the same page over and over again.
+     *    array('q') = Enabled, but only take into account the specified list
+     *                 of query parameters.
+     *
+     * @var bool|string[]
+     */
+    protected $cacheQueryString = false;
+
+    protected CacheInterface $cache;
+
+    public function __construct(CacheConfig $config, CacheInterface $cache)
+    {
+        $this->cacheQueryString = $config->cacheQueryString;
+        $this->cache            = $cache;
+    }
+
+    /**
+     * Generates the cache key to use from the current request.
+     *
+     * @param CLIRequest|IncomingRequest $request
+     *
+     * @internal for testing purposes only
+     */
+    public function generateCacheKey($request): string
+    {
+        if ($request instanceof CLIRequest) {
+            return md5($request->getPath());
+        }
+
+        $uri = clone $request->getUri();
+
+        $query = $this->cacheQueryString
+            ? $uri->getQuery(is_array($this->cacheQueryString) ? ['only' => $this->cacheQueryString] : [])
+            : '';
+
+        return md5($uri->setFragment('')->setQuery($query));
+    }
+
+    /**
+     * Caches the full response from the current request.
+     *
+     * @param CLIRequest|IncomingRequest $request
+     *
+     * @params int $ttl time to live in seconds.
+     */
+    public function cachePage($request, ResponseInterface $response, int $ttl): bool
+    {
+        $headers = [];
+
+        foreach ($response->headers() as $header) {
+            $headers[$header->getName()] = $header->getValueLine();
+        }
+
+        return $this->cache->save(
+            $this->generateCacheKey($request),
+            serialize(['headers' => $headers, 'output' => $response->getBody()]),
+            $ttl
+        );
+    }
+
+    /**
+     * Gets the cached response for the request.
+     *
+     * @param CLIRequest|IncomingRequest $request
+     */
+    public function getCachedResponse($request, ResponseInterface $response): ?ResponseInterface
+    {
+        if ($cachedResponse = $this->cache->get($this->generateCacheKey($request))) {
+            $cachedResponse = unserialize($cachedResponse);
+
+            if (
+                ! is_array($cachedResponse)
+                || ! isset($cachedResponse['output'])
+                || ! isset($cachedResponse['headers'])
+            ) {
+                throw new Exception('Error unserializing page cache');
+            }
+
+            $headers = $cachedResponse['headers'];
+            $output  = $cachedResponse['output'];
+
+            // Clear all default headers
+            foreach (array_keys($response->headers()) as $key) {
+                $response->removeHeader($key);
+            }
+
+            // Set cached headers
+            foreach ($headers as $name => $value) {
+                $response->setHeader($name, $value);
+            }
+
+            $response->setBody($output);
+
+            return $response;
+        }
+
+        return null;
+    }
+}

system/CodeIgniter.php

@@ -12,6 +12,7 @@
 namespace CodeIgniter;
 
 use Closure;
+use CodeIgniter\Cache\PageCache;
 use CodeIgniter\Debug\Timer;
 use CodeIgniter\Events\Events;
 use CodeIgniter\Exceptions\FrameworkException;
@@ -175,13 +176,20 @@ class CodeIgniter
      */
     protected int $bufferLevel;
 
+    /**
+     * Web Page Caching
+     */
+    protected PageCache $pageCache;
+
     /**
      * Constructor.
      */
     public function __construct(App $config)
     {
         $this->startTime = microtime(true);
         $this->config    = $config;
+
+        $this->pageCache = Services::pagecache();
     }
 
     /**
@@ -518,7 +526,7 @@ protected function handleRequest(?RouteCollectionInterface $routes, Cache $cache
             // so that we can have live speed updates along the way.
             // Must be run after filters to preserve the Response headers.
             if (static::$cacheTTL > 0) {
-                $this->cachePage($cacheConfig);
+                $this->pageCache->cachePage($this->request, $this->response, static::$cacheTTL);
             }
 
             // Update the performance metrics
@@ -674,27 +682,11 @@ protected function forceSecureAccess($duration = 31_536_000)
      */
     public function displayCache(Cache $config)
     {
-        if ($cachedResponse = cache()->get($this->generateCacheName($config))) {
-            $cachedResponse = unserialize($cachedResponse);
-            if (! is_array($cachedResponse) || ! isset($cachedResponse['output']) || ! isset($cachedResponse['headers'])) {
-                throw new Exception('Error unserializing page cache');
-            }
-
-            $headers = $cachedResponse['headers'];
-            $output  = $cachedResponse['output'];
-
-            // Clear all default headers
-            foreach (array_keys($this->response->headers()) as $key) {
-                $this->response->removeHeader($key);
-            }
-
-            // Set cached headers
-            foreach ($headers as $name => $value) {
-                $this->response->setHeader($name, $value);
-            }
+        if ($cachedResponse = $this->pageCache->getCachedResponse($this->request, $this->response)) {
+            $this->response = $cachedResponse;
 
             $this->totalTime = $this->benchmark->getElapsedTime('total_execution');
-            $output          = $this->displayPerformanceMetrics($output);
+            $output          = $this->displayPerformanceMetrics($cachedResponse->getBody());
             $this->response->setBody($output);
 
             return $this->response;
@@ -716,6 +708,8 @@ public static function cache(int $time)
      * full-page caching for very high performance.
      *
      * @return bool
+     *
+     * @deprecated 4.4.0 No longer used.
      */
     public function cachePage(Cache $config)
     {
@@ -741,6 +735,8 @@ public function getPerformanceStats(): array
 
     /**
      * Generates the cache name to use for our full-page caching.
+     *
+     * @deprecated 4.4.0 No longer used.
      */
     protected function generateCacheName(Cache $config): string
     {

system/Config/Services.php

@@ -13,6 +13,7 @@
 
 use CodeIgniter\Cache\CacheFactory;
 use CodeIgniter\Cache\CacheInterface;
+use CodeIgniter\Cache\PageCache;
 use CodeIgniter\CLI\Commands;
 use CodeIgniter\CodeIgniter;
 use CodeIgniter\Database\ConnectionInterface;
@@ -438,6 +439,23 @@ public static function negotiator(?RequestInterface $request = null, bool $getSh
         return new Negotiate($request);
     }
 
+    /**
+     * Return the PageCache.
+     *
+     * @return PageCache
+     */
+    public static function pagecache(?Cache $config = null, ?CacheInterface $cache = null, bool $getShared = true)
+    {
+        if ($getShared) {
+            return static::getSharedInstance('pagecache', $config, $cache);
+        }
+
+        $config ??= config(Cache::class);
+        $cache ??= AppServices::cache();
+
+        return new PageCache($config, $cache);
+    }
+
     /**
      * Return the appropriate pagination handler.
      *