Merge pull request #84 from bpolaszek/null-pattern

Null object pattern

src/Storage/LaravelCacheStorage.php

@@ -47,7 +47,7 @@ public function save($key, CacheEntry $data)
             $lifeTime = $data->getTTL() / 60;
             if ($lifeTime === 0) {
                 return $this->cache->forever(
-                    $key, 
+                    $key,
                     serialize($data)
                 );
             } else if ($lifeTime > 0) {

src/Storage/VolatileRuntimeStorage.php

@@ -41,5 +41,4 @@ public function save($key, CacheEntry $data)
 
         return true;
     }
-
 }

src/Strategy/NullCacheStrategy.php

@@ -0,0 +1,35 @@
+<?php
+
+namespace Kevinrob\GuzzleCache\Strategy;
+
+use Kevinrob\GuzzleCache\CacheEntry;
+use Psr\Http\Message\RequestInterface;
+use Psr\Http\Message\ResponseInterface;
+
+class NullCacheStrategy implements CacheStrategyInterface
+{
+
+    /**
+     * @inheritDoc
+     */
+    public function fetch(RequestInterface $request)
+    {
+        return null;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function cache(RequestInterface $request, ResponseInterface $response)
+    {
+        return true;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function update(RequestInterface $request, ResponseInterface $response)
+    {
+        return true;
+    }
+}

tests/NullCacheTest.php

@@ -0,0 +1,36 @@
+<?php
+
+namespace Kevinrob\GuzzleCache;
+
+use GuzzleHttp\Client;
+use GuzzleHttp\Handler\MockHandler;
+use GuzzleHttp\HandlerStack;
+use GuzzleHttp\Psr7\Request;
+use GuzzleHttp\Psr7\Response;
+use Kevinrob\GuzzleCache\Strategy\NullCacheStrategy;
+use PHPUnit\Framework\TestCase;
+
+class NullCacheTest extends TestCase
+{
+
+    public function testCacheIsNeverHit()
+    {
+        $stack = HandlerStack::create(new MockHandler([
+            new Response(),
+            new Response(),
+        ]));
+
+        $stack->push(new CacheMiddleware(new NullCacheStrategy()));
+
+        $request = new Request('GET', '/foo');
+
+        $client = new Client([
+            'handler' => $stack
+        ]);
+        $client->send($request); // Will not be cached
+        $response = $client->send($request); // Will not come from cache
+
+        $this->assertEquals(CacheMiddleware::HEADER_CACHE_MISS, $response->getHeaderLine(CacheMiddleware::HEADER_CACHE_INFO));
+    }
+
+}