Implement request/response decoration

Currently, the `Zend\Stratigility\Next` implementation requires that the
request and response passed to it are the Stratigility-specific
decorators. As such, the `ErrorMiddlewarePipe` is required to decorate
the incoming request and response. I chose to use reflection here so as
not to duplicate logic; ideally, we can remove that requirement from the
Stratigility library in the future.

Author: weierophinney

src/ErrorMiddlewarePipe.php

@@ -11,6 +11,7 @@
 
 use Psr\Http\Message\ServerRequestInterface as Request;
 use Psr\Http\Message\ResponseInterface as Response;
+use ReflectionMethod;
 use ReflectionProperty;
 use Zend\Stratigility\FinalHandler;
 use Zend\Stratigility\MiddlewarePipe;
@@ -63,6 +64,11 @@ public function __construct(MiddlewarePipe $pipeline)
      */
     public function __invoke($error, Request $request, Response $response, callable $out = null)
     {
+        // Decorate instances with Stratigility decorators; required to work
+        // with Next implementation.
+        $request = $this->decorateRequest($request);
+        $response = $this->decorateResponse($response);
+
         $pipeline = $this->getInternalPipeline();
         $done = $out ?: new FinalHandler([], $response);
         $next = new Next($pipeline, $done);
@@ -85,4 +91,34 @@ private function getInternalPipeline()
         $r->setAccessible(true);
         return $r->getValue($this->pipeline);
     }
+
+    /**
+     * Decorate the request with the Stratigility decorator.
+     *
+     * Proxies to the composed MiddlewarePipe's equivalent method.
+     *
+     * @param Request $request
+     * @return \Zend\Stratigility\Http\Request
+     */
+    private function decorateRequest(Request $request)
+    {
+        $r = new ReflectionMethod($this->pipeline, 'decorateRequest');
+        $r->setAccessible(true);
+        return $r->invoke($this->pipeline, $request);
+    }
+
+    /**
+     * Decorate the response with the Stratigility decorator.
+     *
+     * Proxies to the composed MiddlewarePipe's equivalent method.
+     *
+     * @param Response $response
+     * @return \Zend\Stratigility\Http\Response
+     */
+    private function decorateResponse(Response $response)
+    {
+        $r = new ReflectionMethod($this->pipeline, 'decorateResponse');
+        $r->setAccessible(true);
+        return $r->invoke($this->pipeline, $response);
+    }
 }

test/ErrorMiddlewarePipeTest.php

@@ -14,6 +14,7 @@
 use Psr\Http\Message\ResponseInterface as Response;
 use Psr\Http\Message\UriInterface as Uri;
 use Zend\Expressive\ErrorMiddlewarePipe;
+use Zend\Stratigility\Http\Response as StratigilityResponse;
 use Zend\Stratigility\MiddlewarePipe;
 
 class ErrorMiddlewarePipeTest extends TestCase
@@ -56,14 +57,21 @@ public function testWillDispatchErrorMiddlewareComposedInInternalPipeline()
         $uri->getPath()->willReturn('/');
         $request = $this->prophesize(Request::class);
         $request->getUri()->willReturn($uri->reveal());
+
+        // The following is required due to Stratigility decorating requests:
+        $request->withAttribute('originalUri', $uri->reveal())->will(function () use ($request) {
+            return $request->reveal();
+        });
+
         $response = $this->prophesize(Response::class);
 
         $final = function ($request, $response, $err = null) {
             $this->fail('Final handler should not be triggered');
         };
 
         $result = $this->errorPipe->__invoke($error, $request->reveal(), $response->reveal(), $final);
-        $this->assertSame($response->reveal(), $result);
+        $this->assertInstanceOf(StratigilityResponse::class, $result);
+        $this->assertSame($response->reveal(), $result->getOriginalResponse());
         $this->assertTrue($triggered->first);
         $this->assertFalse($triggered->second);
         $this->assertTrue($triggered->third);