Installed and registered new middleware to process IP addresses from request

module/Common/test/Middleware/IpAddressMiddlewareFactoryTest.php

@@ -0,0 +1,36 @@
+<?php
+declare(strict_types=1);
+
+namespace ShlinkioTest\Shlink\Common\Middleware;
+
+use PHPUnit\Framework\TestCase;
+use ReflectionObject;
+use Shlinkio\Shlink\Common\Middleware\IpAddressMiddlewareFactory;
+use Zend\ServiceManager\ServiceManager;
+
+class IpAddressMiddlewareFactoryTest extends TestCase
+{
+    private $factory;
+
+    public function setUp()
+    {
+        $this->factory = new IpAddressMiddlewareFactory();
+    }
+
+    /**
+     * @test
+     */
+    public function returnedInstanceIsProperlyConfigured()
+    {
+        $instance = $this->factory->__invoke(new ServiceManager(), '');
+
+        $ref = new ReflectionObject($instance);
+        $checkProxyHeaders = $ref->getProperty('checkProxyHeaders');
+        $checkProxyHeaders->setAccessible(true);
+        $trustedProxies = $ref->getProperty('trustedProxies');
+        $trustedProxies->setAccessible(true);
+
+        $this->assertTrue($checkProxyHeaders->getValue($instance));
+        $this->assertEquals([], $trustedProxies->getValue($instance));
+    }
+}