Merge pull request #4728 from DaSourcerer/4372-httpcache-rfc7232-compliance

RFC 7232 Compliance for yii\filters\HttpCache

docs/guide/caching-http.md

@@ -108,9 +108,11 @@ since they need to be re-evaluated on every request. Try to find a simple expres
 the cache if the page content has been modified.
 
 
-> Note: In compliant to [RFC 2616, section 13.3.4](http://tools.ietf.org/html/rfc2616#section-13.3.4),
+> Note: In compliance to [RFC 7232, section 2.4](http://tools.ietf.org/html/rfc7232#section-2.4),
   `HttpCache` will send out both `ETag` and `Last-Modified` headers if they are both configured.
-  Consequently, both will be used for cache validation if sent by the client.
+  However, in order to satisfy [section 3.3](http://tools.ietf.org/html/rfc7232#section-3.3) the
+  `If-None-Match` client header will always take precedence over `If-Modified-Since` during validation; meaning
+  latter one is going to be ignored if a `If-None-Match` header is present in the request.
 
 
 ## `Cache-Control` Header <a name="cache-control"></a>

framework/CHANGELOG.md

@@ -171,6 +171,7 @@ Yii Framework 2 Change Log
 - Enh #4297: Added check for DOM extension to requirements (samdark)
 - Enh #4317: Added `absoluteAuthTimeout` to yii\web\User (ivokund, nkovacs)
 - Enh #4360: Added client validation support for file validator (Skysplit)
+- Enh #4372: `yii\filters\HttpCache` failed to comply to RFC 7232
 - Enh #4436: Added callback functions to AJAX-based form validation (thiagotalma)
 - Enh #4485: Added support for deferred validation in `ActiveForm` (Alex-Code)
 - Enh #4520: Added sasl support to `yii\caching\MemCache` (xjflyttp)

framework/filters/HttpCache.php

@@ -150,10 +150,10 @@ class HttpCache extends ActionFilter
      */
     protected function validateCache($lastModified, $etag)
     {
-        if ($lastModified !== null && (!isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) || @strtotime($_SERVER['HTTP_IF_MODIFIED_SINCE']) < $lastModified)) {
-            return false;
+        if($etag !== null && in_array($etag, Yii::$app->request->getEtags(), true)) {
+            return true;
         } else {
-            return $etag === null || in_array($etag, Yii::$app->request->getEtags(), true);
+            return $lastModified !== null && isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) && @strtotime($_SERVER['HTTP_IF_MODIFIED_SINCE']) >= $lastModified;
         }
     }
 

tests/unit/framework/filters/HttpCacheTest.php

@@ -0,0 +1,70 @@
+<?php
+
+namespace yiiunit\framework\filters;
+
+use Yii;
+use yii\filters\HttpCache;
+
+/**
+ * @group filters
+ */
+class HttpCacheTest extends \yiiunit\TestCase
+{
+    protected function setUp()
+    {
+        parent::setUp();
+
+        $_SERVER['SCRIPT_FILENAME'] = "/index.php";
+        $_SERVER['SCRIPT_NAME'] = "/index.php";
+
+        $this->mockWebApplication();
+    }
+
+    public function testDisabled()
+    {
+        $httpCache = new HttpCache;
+        $this->assertTrue($httpCache->beforeAction(null));
+        $httpCache->enabled=false;
+        $this->assertTrue($httpCache->beforeAction(null));
+    }
+
+    /**
+     * @covers yii\filters\HttpCache::validateCache
+     */
+    public function testValidateCache()
+    {
+        $httpCache = new HttpCache;
+        $method = new \ReflectionMethod($httpCache, 'validateCache');
+        $method->setAccessible(true);
+
+        $this->assertFalse($method->invoke($httpCache, null, null));
+
+        $_SERVER['HTTP_IF_MODIFIED_SINCE'] = 'Thu, 01 Jan 1970 00:00:00 GMT';
+        $this->assertTrue($method->invoke($httpCache, 0, null));
+        $this->assertFalse($method->invoke($httpCache, 1, null));
+
+        $_SERVER['HTTP_IF_NONE_MATCH'] = '"foo"';
+        $this->assertTrue($method->invoke($httpCache, 0, '"foo"'));
+        $this->assertTrue($method->invoke($httpCache, 1, '"foo"'));
+        $this->assertFalse($method->invoke($httpCache, null, null));
+    }
+
+    /**
+     * @covers yii\filters\HttpCache::generateEtag
+     */
+    public function testGenerateEtag()
+    {
+        $httpCache = new HttpCache;
+        $httpCache->etagSeed = function($action, $params) {
+            return '';
+        };
+        $httpCache->beforeAction(null);
+        $response = Yii::$app->getResponse();
+
+        $this->assertTrue($response->getHeaders()->offsetExists('ETag'));
+
+        $etag = $response->getHeaders()->get('ETag');
+        $this->assertStringStartsWith('"', $etag);
+        $this->assertStringEndsWith('"', $etag);
+    }
+}