#1: added follow redirect middleware

src/Middleware/FollowRedirectMiddleware.php

@@ -0,0 +1,64 @@
+<?php
+
+namespace DMT\Http\Client\Middleware;
+
+use DMT\Http\Client\MiddlewareInterface;
+use DMT\Http\Client\RequestHandlerInterface;
+use Psr\Http\Message\RequestInterface;
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\UriFactoryInterface;
+
+class FollowRedirectMiddleware implements MiddlewareInterface
+{
+    protected array $statusCodes = [
+        301, // Moved Permanently
+        302, // Found
+        303, // See Other
+        307, // Temporary Redirect
+        308, // Permanent Redirect
+    ];
+
+    private UriFactoryInterface $factory;
+
+    /**
+     * @param UriFactoryInterface $factory
+     * @param array|null $statusCodes
+     */
+    public function __construct(UriFactoryInterface $factory, array $statusCodes = null)
+    {
+        $this->factory = $factory;
+        $this->statusCodes = $statusCodes ?? $this->statusCodes;
+    }
+
+    /**
+     * Automatic follow redirects.
+     *
+     * @param RequestInterface $request
+     * @param RequestHandlerInterface $handler
+     * @return ResponseInterface
+     * @throws ClientExceptionInterface
+     */
+    public function process(RequestInterface $request, RequestHandlerInterface $handler): ResponseInterface
+    {
+        $response = $handler->handle($request);
+
+        if (!in_array($response->getStatusCode(), $this->statusCodes)) {
+            return $response;
+        }
+
+        if (in_array($response->getStatusCode(), [301, 302, 303])
+            && !in_array(strtoupper($request->getMethod()), ['GET', 'HEAD', 'OPTIONS'])
+        ) {
+            $request = $request->withMethod('GET');
+        }
+
+        $location = $response->getHeaderLine('location');
+        if ($location) {
+            $response = $handler->handle(
+                $request->withUri($this->factory->createUri($location))
+            );
+        }
+
+        return $response;
+    }
+}

tests/Middleware/FollowRedirectMiddlewareTest.php

@@ -0,0 +1,93 @@
+<?php
+
+namespace DMT\Test\Http\Client\Middleware;
+
+use DMT\Http\Client\Middleware\FollowRedirectMiddleware;
+use DMT\Http\Client\RequestHandler;
+use GuzzleHttp\Client;
+use GuzzleHttp\Psr7\HttpFactory;
+use GuzzleHttp\Psr7\Request;
+use GuzzleHttp\Psr7\Response;
+use PHPUnit\Framework\TestCase;
+use Psr\Http\Message\RequestInterface;
+
+class FollowRedirectMiddlewareTest extends TestCase
+{
+    /**
+     * @dataProvider provideFollowRedirect
+     *
+     * @param string $method
+     * @param int $statusCode
+     * @param string $expectedMethod
+     */
+    public function testProcess(string $method, int $statusCode, string $expectedMethod)
+    {
+        $client = $this->getMockBuilder(Client::class)
+            ->onlyMethods(['sendRequest'])
+            ->getMockForAbstractClass();
+
+        $client
+            ->expects($this->exactly(2))
+            ->method('sendRequest')
+            ->will(
+                $this->onConsecutiveCalls(
+                    new Response($statusCode, ['Location' => 'https://new-location.org/path']),
+                    $this->returnCallback(
+                        function (RequestInterface $request) {
+                            return new Response(200, ['RequestMethod' => $request->getMethod()]);
+                        }
+                    )
+                )
+            );
+
+        $requestHandler = new RequestHandler($client, new FollowRedirectMiddleware(new HttpFactory()));
+        $response = $requestHandler->handle(new Request($method, 'https://some-location.org/path'));
+
+        $this->assertSame(200, $response->getStatusCode());
+        $this->assertSame($expectedMethod, $response->getHeaderLine('requestMethod'));
+    }
+
+    public function provideFollowRedirect(): iterable
+    {
+        return [
+            ['POST', 301, 'GET'],
+            ['GET', 302, 'GET'],
+            ['HEAD', 302, 'HEAD'],
+            ['PUT', 303, 'GET'],
+            ['PUT', 307, 'PUT'],
+            ['POST', 308, 'POST'],
+        ];
+    }
+
+    /**
+     * @dataProvider provideNoFollow
+     *
+     * @param string $method
+     * @param int $statusCode
+     * @param array $headers
+     */
+    public function testProcessNoFollow(string $method, int $statusCode, array $headers = [])
+    {
+        $client = $this->getMockBuilder(Client::class)
+            ->onlyMethods(['sendRequest'])
+            ->getMockForAbstractClass();
+
+        $client
+            ->expects($this->exactly(1))
+            ->method('sendRequest')
+            ->willReturn($response = new Response($statusCode, $headers));
+
+        $requestHandler = new RequestHandler($client, new FollowRedirectMiddleware(new HttpFactory()));
+
+        $this->assertSame($response, $requestHandler->handle(new Request($method, 'https://some-location.org/path')));
+    }
+
+    public function provideNoFollow(): iterable
+    {
+        return [
+            ['PUT', 300, ['Location' => 'https://new-location.org/path']],
+            ['POST', 303],
+            ['GET', 304],
+        ];
+    }
+}