Use 302 instead of 301 for redirecting unauthenticated requests.

The location isn't permanently moved, therefore using `301` isn't
appropriate.

Author: ndm2

src/Middleware/AuthenticationMiddleware.php

@@ -125,7 +125,7 @@ public function __invoke(ServerRequestInterface $request, ResponseInterface $res
                 $url = $this->getRedirectUrl($target, $request);
 
                 return $response
-                    ->withStatus(301)
+                    ->withStatus(302)
                     ->withHeader('Location', $url);
             }
             throw $e;

tests/TestCase/Middleware/AuthenticationMiddlewareTest.php

@@ -438,7 +438,7 @@ public function testUnauthenticatedRedirect()
         };
 
         $response = $middleware($request, $response, $next);
-        $this->assertSame(301, $response->getStatusCode());
+        $this->assertSame(302, $response->getStatusCode());
         $this->assertSame('/users/login', $response->getHeaderLine('Location'));
         $this->assertSame('', $response->getBody() . '');
     }
@@ -467,7 +467,7 @@ public function testUnauthenticatedRedirectWithQuery()
         };
 
         $response = $middleware($request, $response, $next);
-        $this->assertSame(301, $response->getStatusCode());
+        $this->assertSame(302, $response->getStatusCode());
         $this->assertSame('/users/login?redirect=http%3A%2F%2Flocalhost%2Ftestpath', $response->getHeaderLine('Location'));
         $this->assertSame('', $response->getBody() . '');
     }
@@ -496,7 +496,7 @@ public function testUnauthenticatedRedirectWithExistingQuery()
         };
 
         $response = $middleware($request, $response, $next);
-        $this->assertSame(301, $response->getStatusCode());
+        $this->assertSame(302, $response->getStatusCode());
         $this->assertSame('/users/login?hello=world&redirect=http%3A%2F%2Flocalhost%2Ftestpath', $response->getHeaderLine('Location'));
         $this->assertSame('', $response->getBody() . '');
     }