feature symfony#59068 [HttpClient] Add IPv6 support to NativeHttpClient (dmitrii-baranov-tg)

This PR was squashed before being merged into the 7.3 branch.

Discussion
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[HttpClient] Add IPv6 support to NativeHttpClient

| Q             | A
| ------------- | ---
| Branch?       | 7.3
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | no
| Issues        | Fix symfony#59027
| License       | MIT

[HttpClient] Add IPv6 support to NativeHttpClient

At the moment, NativeHttpClient works only with IPv4 because of the way it does DNS resolution.
But by taking inspiration from DNS resolution in NoPrivateNetworkHttpClient, we are able to make it IPv6 compatible.

Commits
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44a7a58 [HttpClient] Add IPv6 support to NativeHttpClient

Author: nicolas-grekas

src/Symfony/Component/HttpClient/CHANGELOG.md

@@ -1,6 +1,11 @@
 CHANGELOG
 =========
 
+7.3
+---
+
+ * Add IPv6 support to `NativeHttpClient`
+
 7.2
 ---
 

src/Symfony/Component/HttpClient/NativeHttpClient.php

@@ -332,25 +332,38 @@ private static function dnsResolve(string $host, NativeClientState $multi, array
     {
         $flag = '' !== $host && '[' === $host[0] && ']' === $host[-1] && str_contains($host, ':') ? \FILTER_FLAG_IPV6 : \FILTER_FLAG_IPV4;
         $ip = \FILTER_FLAG_IPV6 === $flag ? substr($host, 1, -1) : $host;
+        $now = microtime(true);
 
         if (filter_var($ip, \FILTER_VALIDATE_IP, $flag)) {
             // The host is already an IP address
         } elseif (null === $ip = $multi->dnsCache[$host] ?? null) {
             $info['debug'] .= "* Hostname was NOT found in DNS cache\n";
-            $now = microtime(true);
 
-            if (!$ip = gethostbynamel($host)) {
+            if ($ip = gethostbynamel($host)) {
+                $ip = $ip[0];
+            } elseif (!\defined('STREAM_PF_INET6')) {
+                throw new TransportException(\sprintf('Could not resolve host "%s".', $host));
+            } elseif ($ip = dns_get_record($host, \DNS_AAAA)) {
+                $ip = $ip[0]['ipv6'];
+            } elseif (\extension_loaded('sockets')) {
+                if (!$addrInfo = socket_addrinfo_lookup($host, 0, ['ai_socktype' => \SOCK_STREAM, 'ai_family' => \AF_INET6])) {
+                    throw new TransportException(\sprintf('Could not resolve host "%s".', $host));
+                }
+
+                $ip = socket_addrinfo_explain($addrInfo[0])['ai_addr']['sin6_addr'];
+            } elseif ('localhost' === $host || 'localhost.' === $host) {
+                $ip = '::1';
+            } else {
                 throw new TransportException(\sprintf('Could not resolve host "%s".', $host));
             }
 
-            $multi->dnsCache[$host] = $ip = $ip[0];
+            $multi->dnsCache[$host] = $ip;
             $info['debug'] .= "* Added {$host}:0:{$ip} to DNS cache\n";
-            $host = $ip;
         } else {
             $info['debug'] .= "* Hostname was found in DNS cache\n";
-            $host = str_contains($ip, ':') ? "[$ip]" : $ip;
         }
 
+        $host = str_contains($ip, ':') ? "[$ip]" : $ip;
         $info['namelookup_time'] = microtime(true) - ($info['start_time'] ?: $now);
         $info['primary_ip'] = $ip;
 

src/Symfony/Component/HttpClient/Tests/NativeHttpClientTest.php

@@ -11,8 +11,10 @@
 
 namespace Symfony\Component\HttpClient\Tests;
 
+use Symfony\Bridge\PhpUnit\DnsMock;
 use Symfony\Component\HttpClient\NativeHttpClient;
 use Symfony\Contracts\HttpClient\HttpClientInterface;
+use Symfony\Contracts\HttpClient\Test\TestHttpServer;
 
 /**
  * @group dns-sensitive
@@ -48,4 +50,25 @@ public function testHttp2PushVulcainWithUnusedResponse()
     {
         $this->markTestSkipped('NativeHttpClient doesn\'t support HTTP/2.');
     }
+
+    public function testIPv6Resolve()
+    {
+        TestHttpServer::start(-8087);
+
+        DnsMock::withMockedHosts([
+            'symfony.com' => [
+                [
+                    'type' => 'AAAA',
+                    'ipv6' => '::1',
+                ],
+            ],
+        ]);
+
+        $client = $this->getHttpClient(__FUNCTION__);
+        $response = $client->request('GET', 'http://symfony.com:8087/');
+
+        $this->assertSame(200, $response->getStatusCode());
+
+        DnsMock::withMockedHosts([]);
+    }
 }