symfony · fabpot · Apr 1, 2022 · Dec 3, 2021
diff --git a/src/Symfony/Component/Mailer/CHANGELOG.md b/src/Symfony/Component/Mailer/CHANGELOG.md
@@ -5,6 +5,7 @@ CHANGELOG
 ---
 
  * Make `start()` and `stop()` methods public on `SmtpTransport`
+ * Improve extensibility of `EsmtpTransport`
 
 6.0
 ---

diff --git a/src/Symfony/Component/Mailer/Tests/Transport/Smtp/DummyStream.php b/src/Symfony/Component/Mailer/Tests/Transport/Smtp/DummyStream.php
@@ -0,0 +1,110 @@
+<?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\Mailer\Tests\Transport\Smtp;
+
+use Symfony\Component\Mailer\Exception\TransportException;
+use Symfony\Component\Mailer\Transport\Smtp\Stream\AbstractStream;
+
+class DummyStream extends AbstractStream
+{
+    private string $nextResponse;
+    private array $commands = [];
+    private bool $closed = true;
+
+    public function initialize(): void
+    {
+        $this->closed = false;
+        $this->nextResponse = '220 localhost ESMTP';
+    }
+
+    public function disableTls(): static
+    {
+        return $this;
+    }
+
+    public function isTLS(): bool
+    {
+        return false;
+    }
+
+    public function setHost(string $host): static
+    {
+        return $this;
+    }
+
+    public function setPort(int $port): static
+    {
+        return $this;
+    }
+
+    public function write(string $bytes, $debug = true): void
+    {
+        if ($this->closed) {
+            throw new TransportException('Unable to write bytes on the wire.');
+        }
+
+        $this->commands[] = $bytes;
+
+        if (str_starts_with($bytes, 'EHLO')) {
+            $this->nextResponse = '250 localhost';
+        } elseif (str_starts_with($bytes, 'DATA')) {
+            $this->nextResponse = '354 Enter message, ending with "." on a line by itself';
+        } elseif (str_starts_with($bytes, 'QUIT')) {
+            $this->nextResponse = '221 Goodbye';
+        } else {
+            $this->nextResponse = '250 OK';
+        }
+    }
+
+    public function readLine(): string
+    {
+        return $this->nextResponse."\r\n";
+    }
+
+    public function flush(): void
+    {
+    }
+
+    /**
+     * @return string[]
+     */
+    public function getCommands(): array
+    {
+        return $this->commands;
+    }
+
+    public function clearCommands(): void
+    {
+        $this->commands = [];
+    }
+
+    protected function getReadConnectionDescription(): string
+    {
+        return 'null';
+    }
+
+    public function close(): void
+    {
+        $this->closed = true;
+    }
+
+    public function isClosed(): bool
+    {
+        return $this->closed;
+    }
+
+    public function terminate(): void
+    {
+        parent::terminate();
+        $this->closed = true;
+    }
+}
diff --git a/src/Symfony/Component/Mailer/Tests/Transport/Smtp/EsmtpTransportTest.php b/src/Symfony/Component/Mailer/Tests/Transport/Smtp/EsmtpTransportTest.php
@@ -13,6 +13,7 @@
 
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\Mailer\Transport\Smtp\EsmtpTransport;
+use Symfony\Component\Mime\Email;
 
 class EsmtpTransportTest extends TestCase
 {
@@ -40,4 +41,40 @@ public function testToString()
         $t = new EsmtpTransport('example.com', 466, true);
         $this->assertEquals('smtps://example.com:466', (string) $t);
     }
+
+    public function testExtensibility()
+    {
+        $stream = new DummyStream();
+        $transport = new CustomEsmtpTransport(stream: $stream);
+
+        $message = new Email();
+        $message->from('sender@example.org');
+        $message->addTo('recipient@example.org');
+        $message->text('.');
+
+        $transport->send($message);
+
+        $this->assertContains("MAIL FROM:<sender@example.org> RET=HDRS\r\n", $stream->getCommands());
+        $this->assertContains("RCPT TO:<recipient@example.org> NOTIFY=FAILURE\r\n", $stream->getCommands());
+    }
+}
+
+class CustomEsmtpTransport extends EsmtpTransport
+{
+    public function executeCommand(string $command, array $codes): string
+    {
+        $command = match (true) {
+            str_starts_with($command, 'MAIL FROM:') && isset($this->getCapabilities()['DSN']) => substr_replace($command, ' RET=HDRS', -2, 0),
+            str_starts_with($command, 'RCPT TO:') && isset($this->getCapabilities()['DSN']) => substr_replace($command, ' NOTIFY=FAILURE', -2, 0),
+            default => $command,
+        };
+
+        $response = parent::executeCommand($command, $codes);
+
+        if (str_starts_with($command, 'EHLO ')) {
+            $response .= "250 DSN\r\n";
+        }
+
+        return $response;
+    }
 }
diff --git a/src/Symfony/Component/Mailer/Tests/Transport/Smtp/SmtpTransportTest.php b/src/Symfony/Component/Mailer/Tests/Transport/Smtp/SmtpTransportTest.php
@@ -15,7 +15,6 @@
 use Symfony\Component\Mailer\Envelope;
 use Symfony\Component\Mailer\Exception\TransportException;
 use Symfony\Component\Mailer\Transport\Smtp\SmtpTransport;
-use Symfony\Component\Mailer\Transport\Smtp\Stream\AbstractStream;
 use Symfony\Component\Mailer\Transport\Smtp\Stream\SocketStream;
 use Symfony\Component\Mime\Address;
 use Symfony\Component\Mime\Email;
@@ -147,87 +146,3 @@ public function testStop()
         $this->assertTrue($stream->isClosed());
     }
 }
-
-class DummyStream extends AbstractStream
-{
-    /**
-     * @var string
-     */
-    private $nextResponse;
-
-    /**
-     * @var string[]
-     */
-    private $commands;
-
-    /**
-     * @var bool
-     */
-    private $closed = true;
-
-    public function initialize(): void
-    {
-        $this->closed = false;
-        $this->nextResponse = '220 localhost';
-    }
-
-    public function write(string $bytes, $debug = true): void
-    {
-        if ($this->closed) {
-            throw new TransportException('Unable to write bytes on the wire.');
-        }
-
-        $this->commands[] = $bytes;
-
-        if (str_starts_with($bytes, 'DATA')) {
-            $this->nextResponse = '354 Enter message, ending with "." on a line by itself';
-        } elseif (str_starts_with($bytes, 'QUIT')) {
-            $this->nextResponse = '221 Goodbye';
-        } else {
-            $this->nextResponse = '250 OK';
-        }
-    }
-
-    public function readLine(): string
-    {
-        return $this->nextResponse;
-    }
-
-    public function flush(): void
-    {
-    }
-
-    /**
-     * @return string[]
-     */
-    public function getCommands(): array
-    {
-        return $this->commands;
-    }
-
-    public function clearCommands(): void
-    {
-        $this->commands = [];
-    }
-
-    protected function getReadConnectionDescription(): string
-    {
-        return 'null';
-    }
-
-    public function close(): void
-    {
-        $this->closed = true;
-    }
-
-    public function isClosed(): bool
-    {
-        return $this->closed;
-    }
-
-    public function terminate(): void
-    {
-        parent::terminate();
-        $this->closed = true;
-    }
-}
diff --git a/src/Symfony/Component/Mailer/Transport/Smtp/EsmtpTransport.php b/src/Symfony/Component/Mailer/Transport/Smtp/EsmtpTransport.php
@@ -16,6 +16,7 @@
 use Symfony\Component\Mailer\Exception\TransportException;
 use Symfony\Component\Mailer\Exception\TransportExceptionInterface;
 use Symfony\Component\Mailer\Transport\Smtp\Auth\AuthenticatorInterface;
+use Symfony\Component\Mailer\Transport\Smtp\Stream\AbstractStream;
 use Symfony\Component\Mailer\Transport\Smtp\Stream\SocketStream;
 
 /**
@@ -29,10 +30,11 @@ class EsmtpTransport extends SmtpTransport
     private array $authenticators = [];
     private string $username = '';
     private string $password = '';
+    private array $capabilities;
 
-    public function __construct(string $host = 'localhost', int $port = 0, bool $tls = null, EventDispatcherInterface $dispatcher = null, LoggerInterface $logger = null)
+    public function __construct(string $host = 'localhost', int $port = 0, bool $tls = null, EventDispatcherInterface $dispatcher = null, LoggerInterface $logger = null, AbstractStream $stream = null)
     {
-        parent::__construct(null, $dispatcher, $logger);
+        parent::__construct($stream, $dispatcher, $logger);
 
         // order is important here (roughly most secure and popular first)
         $this->authenticators = [
@@ -98,24 +100,32 @@ public function addAuthenticator(AuthenticatorInterface $authenticator): void
         $this->authenticators[] = $authenticator;
     }
 
-    protected function doHeloCommand(): void
+    public function executeCommand(string $command, array $codes): string
+    {
+        return [250] === $codes && str_starts_with($command, 'HELO ') ? $this->doEhloCommand() : parent::executeCommand($command, $codes);
+    }
+
+    final protected function getCapabilities(): array
+    {
+        return $this->capabilities;
+    }
+
+    private function doEhloCommand(): string
     {
         try {
             $response = $this->executeCommand(sprintf("EHLO %s\r\n", $this->getLocalDomain()), [250]);
         } catch (TransportExceptionInterface $e) {
-            parent::doHeloCommand();
-
-            return;
+            return parent::executeCommand(sprintf("HELO %s\r\n", $this->getLocalDomain()), [250]);
         }
 
-        $capabilities = $this->getCapabilities($response);
+        $this->capabilities = $this->parseCapabilities($response);
 
         /** @var SocketStream $stream */
         $stream = $this->getStream();
         // WARNING: !$stream->isTLS() is right, 100% sure :)
         // if you think that the ! should be removed, read the code again
         // if doing so "fixes" your issue then it probably means your SMTP server behaves incorrectly or is wrongly configured
-        if (!$stream->isTLS() && \defined('OPENSSL_VERSION_NUMBER') && \array_key_exists('STARTTLS', $capabilities)) {
+        if (!$stream->isTLS() && \defined('OPENSSL_VERSION_NUMBER') && \array_key_exists('STARTTLS', $this->capabilities)) {
             $this->executeCommand("STARTTLS\r\n", [220]);
 
             if (!$stream->startTLS()) {
@@ -124,20 +134,20 @@ protected function doHeloCommand(): void
 
             try {
                 $response = $this->executeCommand(sprintf("EHLO %s\r\n", $this->getLocalDomain()), [250]);
-                $capabilities = $this->getCapabilities($response);
+                $this->capabilities = $this->parseCapabilities($response);
             } catch (TransportExceptionInterface $e) {
-                parent::doHeloCommand();
-
-                return;
+                return parent::executeCommand(sprintf("HELO %s\r\n", $this->getLocalDomain()), [250]);
             }
         }
 
-        if (\array_key_exists('AUTH', $capabilities)) {
-            $this->handleAuth($capabilities['AUTH']);
+        if (\array_key_exists('AUTH', $this->capabilities)) {
+            $this->handleAuth($this->capabilities['AUTH']);
         }
+
+        return $response;
     }
 
-    private function getCapabilities(string $ehloResponse): array
+    private function parseCapabilities(string $ehloResponse): array
     {
         $capabilities = [];
         $lines = explode("\r\n", trim($ehloResponse));

diff --git a/src/Symfony/Component/Mailer/Transport/Smtp/SmtpTransport.php b/src/Symfony/Component/Mailer/Transport/Smtp/SmtpTransport.php
@@ -172,8 +172,6 @@ public function __toString(): string
      * @param int[] $codes
      *
      * @throws TransportException when an invalid response if received
-     *
-     * @internal
      */
     public function executeCommand(string $command, array $codes): string
     {
@@ -225,6 +223,10 @@ protected function doSend(SentMessage $message): void
         }
     }
 
+    /**
+     * @internal since version 6.1, to be made private in 7.0
+     * @final since version 6.1, to be made private in 7.0
+     */
     protected function doHeloCommand(): void
     {
         $this->executeCommand(sprintf("HELO %s\r\n", $this->domain), [250]);
-Original file line number
+Diff line change
@@ Expand Up / @@ -5,6 +5,7 @@ CHANGELOG @@
     ---
      * Make `start()` and `stop()` methods public on `SmtpTransport`
+     * Improve extensibility of `EsmtpTransport`
 .0
     ---
@@ Expand Down @@