feature #30625 [HttpKernel] add RealHttpKernel: handle requests with …

…HttpClientInterface (fabpot)

This PR was merged into the 4.3-dev branch.

Discussion
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[HttpKernel] add RealHttpKernel: handle requests with HttpClientInterface

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

This commit is directly extracted from #30602 by @fabpot

Commits
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b579b02 [HttpKernel] add RealHttpKernel: handle requests with HttpClientInterface

src/Symfony/Component/HttpKernel/CHANGELOG.md

@@ -21,6 +21,7 @@ CHANGELOG
  * renamed `GetResponseForControllerResultEvent` to `ViewEvent`
  * renamed `GetResponseForExceptionEvent` to `ExceptionEvent`
  * renamed `PostResponseEvent` to `TerminateEvent`
+ * added `RealHttpKernel` for handling requests with an `HttpClientInterface` instance
 
 4.2.0
 -----

src/Symfony/Component/HttpKernel/RealHttpKernel.php

@@ -0,0 +1,104 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\HttpKernel;
+
+use Psr\Log\LoggerInterface;
+use Psr\Log\NullLogger;
+use Symfony\Component\HttpClient\HttpClient;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Response;
+use Symfony\Component\Mime\Part\AbstractPart;
+use Symfony\Component\Mime\Part\DataPart;
+use Symfony\Component\Mime\Part\Multipart\FormDataPart;
+use Symfony\Component\Mime\Part\TextPart;
+use Symfony\Contracts\HttpClient\HttpClientInterface;
+
+/**
+ * An implementation of a Symfony HTTP kernel using a "real" HTTP client.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+final class RealHttpKernel implements HttpKernelInterface
+{
+    private $client;
+    private $logger;
+
+    public function __construct(HttpClientInterface $client = null, LoggerInterface $logger = null)
+    {
+        if (!class_exists(HttpClient::class)) {
+            throw new \LogicException(sprintf('You cannot use "%s" as the HttpClient component is not installed. Try running "composer require symfony/http-client".', __CLASS__));
+        }
+
+        $this->client = $client ?? HttpClient::create();
+        $this->logger = $logger ?? new NullLogger();
+    }
+
+    public function handle(Request $request, $type = HttpKernelInterface::MASTER_REQUEST, $catch = true)
+    {
+        $this->logger->debug(sprintf('Request: %s %s', $request->getMethod(), $request->getUri()));
+
+        $headers = $this->getHeaders($request);
+        $body = '';
+        if (null !== $part = $this->getBody($request)) {
+            $headers = array_merge($headers, $part->getPreparedHeaders()->toArray());
+            $body = $part->bodyToIterable();
+        }
+        $response = $this->client->request($request->getMethod(), $request->getUri(), [
+            'headers' => $headers,
+            'body' => $body,
+            'max_redirects' => 0,
+        ] + $request->attributes->get('http_client_options', []));
+
+        $this->logger->debug(sprintf('Response: %s %s', $response->getStatusCode(), $request->getUri()));
+
+        return new Response($response->getContent(!$catch), $response->getStatusCode(), $response->getHeaders(!$catch));
+    }
+
+    private function getBody(Request $request): ?AbstractPart
+    {
+        if (\in_array($request->getMethod(), ['GET', 'HEAD'])) {
+            return null;
+        }
+
+        if (!class_exists(AbstractPart::class)) {
+            throw new \LogicException('You cannot pass non-empty bodies as the Mime component is not installed. Try running "composer require symfony/mime".');
+        }
+
+        if ($content = $request->getContent()) {
+            return new TextPart($content, 'utf-8', 'plain', '8bit');
+        }
+
+        $fields = $request->request->all();
+        foreach ($request->files->all() as $name => $file) {
+            $fields[$name] = DataPart::fromPath($file->getPathname(), $file->getClientOriginalName(), $file->getClientMimeType());
+        }
+
+        return new FormDataPart($fields);
+    }
+
+    private function getHeaders(Request $request): array
+    {
+        $headers = [];
+        foreach ($request->headers as $key => $value) {
+            $headers[$key] = $value;
+        }
+        $cookies = [];
+        foreach ($request->cookies->all() as $name => $value) {
+            $cookies[] = $name.'='.$value;
+        }
+        if ($cookies) {
+            $headers['cookie'] = implode('; ', $cookies);
+        }
+
+        return $headers;
+    }
+}