cache response

Signed-off-by: cyd622 <luffywang622@gmail.com>

Author: cyd622

src/Middleware/CacheResponseMiddleware.php

@@ -0,0 +1,194 @@
+<?php
+/**
+ * Description: 页面缓存中间件
+ * Project: laravel_api
+ * Author: Ciel (luffywang622@gmail.com)
+ * Created on: 2019/04/03 10:53
+ * Created by PhpStorm.
+ */
+
+namespace Cyd622\LaravelApi\Middleware;
+
+use Illuminate\Http\Request;
+
+class CacheResponseMiddleware
+{
+    /**
+     * the cache tag
+     */
+    const CACHE_TAG = 'PageCache';
+
+    /**
+     * @var \Illuminate\Http\Request
+     */
+    protected $request;
+
+    /**
+     * @var \Closure
+     */
+    protected $next;
+
+    /**
+     * 缓存分钟
+     *
+     * @var int|null
+     */
+    protected $minutes;
+
+    /**
+     * 缓存数据
+     *
+     * @var array
+     */
+    protected $cacheContent;
+
+    /**
+     * 缓存命中状态，1为命中，0为未命中
+     *
+     * @var int
+     */
+    protected $cacheHit = 1;
+
+    /**
+     * 缓存Key
+     *
+     * @var string
+     */
+    protected $cacheKey;
+
+    /**
+     * Handle an incoming request
+     * @param $request
+     * @param \Closure $next
+     * @param null $minutes
+     *
+     * @return mixed
+     */
+    public function handle(Request $request, \Closure $next, $minutes = null)
+    {
+
+        $this->prepare($request, $next, $minutes);
+
+        // skip cache
+        if ($request->has('skip_cache')) {
+            return $next($request);
+        }
+
+        // flush cache
+        if ($request->has('flush_cache')) {
+            $this->cacheSet()->flush();
+            return $next($request);
+        }
+
+        // clear current request cache
+        if ($request->has('clear_cache')) {
+            $this->cacheSet()->forget($this->cacheKey);
+            return $next($request);
+        }
+
+        $this->responseCache();
+
+        $response = \response()->make($this->cacheContent, 200, $this->getHeaders());
+        if ($response->isSuccessful() && !$response->headers->has('ETag')) {
+            $response->setEtag(sha1($response->getContent()));
+        }
+
+        $response->isNotModified(app('request'));
+        return $response;
+    }
+
+    /**
+     * resolve value
+     * @param $request
+     * @param \Closure $next
+     * @param null $minutes
+     */
+    protected function prepare($request, \Closure $next, $minutes = null)
+    {
+        $this->request = $request;
+        $this->next = $next;
+        $this->cacheKey = $this->resolveKey();
+        $this->minutes = $this->resolveMinutes($minutes);
+    }
+
+    /**
+     * cache this response content
+     */
+    protected function responseCache()
+    {
+        $this->cacheContent = $this->cacheSet()->remember(
+            $this->cacheKey,
+            $this->minutes,
+            function () {
+                $this->cacheMissed();
+
+                /** @var \Illuminate\Http\Response $response */
+                $response = ($this->next)($this->request);
+
+                // json数据是需要解析成数组格式
+                if ($response instanceof \Illuminate\Http\JsonResponse) {
+                    return $response->getData(true);
+                }
+
+                return $response->getContent();
+            }
+        );
+    }
+
+    /**
+     * @return array
+     */
+    protected function getHeaders()
+    {
+        $headers = [
+            'X-Cache' => $this->cacheHit ? 'Hit from cache' : 'Missed',
+            'X-Cache-Key' => $this->cacheKey,
+            'X-Cache-Expires' => now()->addMinutes($this->minutes)->format('Y-m-d H:i:s T'),
+        ];
+        return $headers;
+    }
+
+    /**
+     * @return string
+     */
+    protected function resolveKey()
+    {
+        $queryKeys = ['skip_cache', 'flush_cache', 'clear_cache'];
+        $query = $this->request->except($queryKeys);
+        return md5($this->request->url() . json_encode($query) . $this->request->server('HTTP_X_REQUESTED_WITH'));
+    }
+
+
+    /**
+     * @return \Illuminate\Cache\CacheManager|\Illuminate\Cache\TaggedCache|\Illuminate\Foundation\Application|mixed
+     */
+    protected function cacheSet()
+    {
+        if (\Cache::getStore() instanceof \Illuminate\Cache\TaggableStore) {
+            return \Cache::tags(self::CACHE_TAG);
+        }
+        $this->cacheKey = self::CACHE_TAG . '.' . $this->cacheKey;
+        return app('cache');
+    }
+
+    /**
+     * @param null $minutes
+     * @return int|mixed
+     */
+    protected function resolveMinutes($minutes = null)
+    {
+        return is_null($minutes)
+            ? $this->getDefaultMinutes()
+            : max($this->getDefaultMinutes(), intval($minutes));
+    }
+
+    protected function getDefaultMinutes()
+    {
+        return 10;
+    }
+
+    protected function cacheMissed()
+    {
+        $this->cacheHit = 0;
+    }
+}