class ReverseProxyMiddlewareTest

class ReverseProxyMiddlewareTest extends UnitTestCase {

  /**
   * @var \Symfony\Component\HttpKernel\HttpKernelInterface|\PHPUnit\Framework\MockObject\MockObject
   */
  protected $mockHttpKernel;

  /**
   * {@inheritdoc}
   */
  protected function setUp() : void {
    parent::setUp();
    $responseMock = $this
      ->createMock(Response::class);
    $this->mockHttpKernel = $this
      ->createMock(HttpKernelInterface::class);
    $this->mockHttpKernel
      ->method('handle')
      ->willReturn($responseMock);
  }

  /**
   * Tests that subscriber does not act when reverse proxy is not set.
   */
  public function testNoProxy() {
    $settings = new Settings([]);
    $this
      ->assertEquals(0, $settings
      ->get('reverse_proxy'));
    $middleware = new ReverseProxyMiddleware($this->mockHttpKernel, $settings);

    // Mock a request object.
    $request = $this
      ->getMockBuilder('Symfony\\Component\\HttpFoundation\\Request')
      ->onlyMethods([
      'setTrustedProxies',
    ])
      ->getMock();

    // setTrustedProxies() should never fire.
    $request
      ->expects($this
      ->never())
      ->method('setTrustedProxies');

    // Actually call the check method.
    $middleware
      ->handle($request);
  }

  /**
   * Tests that subscriber sets trusted headers when reverse proxy is set.
   *
   * @dataProvider reverseProxyEnabledProvider
   */
  public function testReverseProxyEnabled($provided_settings, $expected_trusted_header_set) {

    // Enable reverse proxy and add test values.
    $settings = new Settings([
      'reverse_proxy' => 1,
    ] + $provided_settings);
    $this
      ->trustedHeadersAreSet($settings, $expected_trusted_header_set);
  }

  /**
   * Data provider for testReverseProxyEnabled.
   */
  public static function reverseProxyEnabledProvider() {
    return [
      'Proxy with default trusted headers' => [
        [
          'reverse_proxy_addresses' => [
            '127.0.0.2',
            '127.0.0.3',
          ],
        ],
        Request::HEADER_FORWARDED | Request::HEADER_X_FORWARDED_FOR | Request::HEADER_X_FORWARDED_HOST | Request::HEADER_X_FORWARDED_PORT | Request::HEADER_X_FORWARDED_PROTO,
      ],
      'Proxy with AWS trusted headers' => [
        [
          'reverse_proxy_addresses' => [
            '127.0.0.2',
            '127.0.0.3',
          ],
          'reverse_proxy_trusted_headers' => Request::HEADER_X_FORWARDED_AWS_ELB,
        ],
        Request::HEADER_X_FORWARDED_AWS_ELB,
      ],
      'Proxy with custom trusted headers' => [
        [
          'reverse_proxy_addresses' => [
            '127.0.0.2',
            '127.0.0.3',
          ],
          'reverse_proxy_trusted_headers' => Request::HEADER_X_FORWARDED_FOR | Request::HEADER_X_FORWARDED_HOST,
        ],
        Request::HEADER_X_FORWARDED_FOR | Request::HEADER_X_FORWARDED_HOST,
      ],
    ];
  }

  /**
   * Tests that trusted headers are set correctly.
   *
   * \Symfony\Component\HttpFoundation\Request::setTrustedProxies() should
   * always be called when reverse proxy settings are enabled.
   *
   * @param \Drupal\Core\Site\Settings $settings
   *   The settings object that holds reverse proxy configuration.
   * @param int $expected_trusted_header_set
   *   The expected bit value returned by
   *   \Symfony\Component\HttpFoundation\Request::getTrustedHeaderSet()
   */
  protected function trustedHeadersAreSet(Settings $settings, $expected_trusted_header_set) {
    $middleware = new ReverseProxyMiddleware($this->mockHttpKernel, $settings);
    $request = new Request();
    $middleware
      ->handle($request);
    $this
      ->assertSame($settings
      ->get('reverse_proxy_addresses'), $request
      ->getTrustedProxies());
    $this
      ->assertSame($expected_trusted_header_set, $request
      ->getTrustedHeaderSet());
  }

}