Use the first location header object as the original redirect uri

.travis.yml

@@ -9,6 +9,8 @@ php:
 
 sudo: false
 
+dist: trusty
+
 before_script:
   - composer self-update
   - travis_retry composer install --no-interaction --prefer-source

src/Filter/RewriteLocationFilter.php

@@ -17,7 +17,8 @@ public function __invoke(RequestInterface $request, ResponseInterface $response,
         $response = $next($request, $response);
 
         if ($response->hasHeader(self::LOCATION)) {
-            $original = parse_url($response->getHeader(self::LOCATION));
+            $location = $response->getHeader(self::LOCATION)[0];
+            $original = parse_url($location);
 
             $target = rtrim(str_replace(basename($_SERVER['SCRIPT_NAME']), '', $_SERVER['SCRIPT_NAME']), '/');
 
@@ -30,10 +31,9 @@ public function __invoke(RequestInterface $request, ResponseInterface $response,
             }
 
             $response = $response
-                ->withHeader('X-Proxy-Location', $response->getHeader(self::LOCATION))
+                ->withHeader('X-Proxy-Location', $location)
                 ->withHeader(self::LOCATION, $target);
         }
-
         return $response;
     }
 }

tests/Proxy/Filter/RewriteLocationFilterTest.php

@@ -0,0 +1,36 @@
+<?php namespace Proxy\Filter;
+
+use Zend\Diactoros\Request;
+use Zend\Diactoros\Response;
+
+class RewriteLocationFilterTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @var RewriteLocationFilter
+     */
+    private $filter;
+
+    public function setUp()
+    {
+        $this->filter = new RewriteLocationFilter();
+    }
+
+    /**
+     * @test
+     */
+    public function filter_rewrites_location()
+    {
+        $_SERVER['SCRIPT_NAME'] = "";
+        $redirect_url = 'http://www.example.com/path?arg1=123&arg2=456';
+        $request = new Request;
+        $response = new Response('php://memory', 200, [RewriteLocationFilter::LOCATION => $redirect_url]);
+        $next = function () use ($response) { return $response; };
+
+        $response = call_user_func($this->filter, $request, $response, $next);
+
+        $this->assertTrue($response->hasHeader('X-Proxy-Location'));
+        $this->assertTrue($response->hasHeader(RewriteLocationFilter::LOCATION));
+        $this->assertEquals('/path?arg1=123&arg2=456', $response->getHeaderLine(RewriteLocationFilter::LOCATION));
+    }
+
+}