Support multiple emails in one connection

src/Sender/MailToFileSender.php

@@ -47,30 +47,32 @@ public function send(iterable $frames): void
     /**
      * Get normalized email address for file or directory name.
      *
-     * @return non-empty-string
+     * @return non-empty-string|null
      */
-    private static function normalizeEmail(string $email): string
+    private static function normalizeEmail(?string $email): ?string
     {
-        return \preg_replace(
+        $normalized = \preg_replace(
             ['/[^a-z0-9.\\- @]/i', '/\s+/'],
             ['!', '_'],
-            $email,
+            (string) $email,
         );
+
+        return $normalized === '' ? null : $normalized;
     }
 
     /**
      * @return list<non-empty-string>
      */
     private static function fetchDirectories(Message\Smtp $message): array
     {
-        return
-            \array_filter(
-                \array_unique(
-                    \array_map(
-                        static fn(Contact $c) => self::normalizeEmail($c->email),
-                        \array_merge($message->getBcc(), $message->getTo()),
-                    ),
+        return \array_values(\array_filter(
+            \array_unique(
+                \array_map(
+                    static fn(Contact $c): ?string => self::normalizeEmail($c->email),
+                    \array_merge($message->getBcc(), $message->getTo()),
                 ),
-            );
+            ),
+            static fn(?string $dir): bool => $dir !== null,
+        ));
     }
 }

src/Test/Mock/StreamClientMock.php

@@ -16,13 +16,17 @@ final class StreamClientMock implements StreamClient
     /** @var \SplQueue<string> */
     private \SplQueue $queue;
 
+    private string $sendBuffer = '';
     private bool $disconnected = false;
 
     private function __construct(
         private readonly \Generator $generator,
         private readonly \DateTimeInterface $createdAt = new \DateTimeImmutable(),
     ) {
         $this->queue = new \SplQueue();
+        // init the Generator
+        $value = (string) $this->generator->current();
+        $value === '' or $this->queue->enqueue($value);
     }
 
     public static function createFromGenerator(\Generator $generator): StreamClient
@@ -51,7 +55,7 @@ public function sendData(string $data): bool
         }
 
         $this->fetchFromGenerator();
-        $this->generator->send($data);
+        $this->sendBuffer .= $data;
 
         return true;
     }
@@ -141,12 +145,8 @@ private function fetchFromGenerator(): void
         if ($this->isFinished()) {
             return;
         }
-        $value = (string) $this->generator->current();
-
-        if ($value !== '') {
-            $this->queue->enqueue($value);
-        }
-
-        $this->generator->next();
+        [$toSend, $this->sendBuffer] = [$this->sendBuffer, ''];
+        $value = (string) $this->generator->send($toSend);
+        $value === '' or $this->queue->enqueue($value);
     }
 }

src/Traffic/Dispatcher/Smtp.php

@@ -27,16 +27,18 @@ public function __construct(
         $this->parser = new Parser\Smtp();
     }
 
+    // todo support Auth https://www.rfc-editor.org/rfc/rfc4954
     public function dispatch(StreamClient $stream): iterable
     {
         $stream->sendData($this->createResponse(self::READY, 'mailamie'));
         $protocol = [];
-
-        $message = null;
         while (!$stream->isFinished()) {
-            $response = $stream->fetchLine();
-            if (\preg_match('/^(?:EHLO|HELO)/', $response)) {
+            $response = \ltrim($stream->fetchLine(), ' ');
+            if (\str_starts_with($response, 'NOOP')) {
+                $stream->sendData($this->createResponse(self::OK));
+            } elseif (\preg_match('/^(?:EHLO|HELO|RSET)/', $response)) {
                 $stream->sendData($this->createResponse(self::OK));
+                $protocol = [];
             } elseif (\preg_match('/^MAIL FROM:\s*<(.*)>/', $response, $matches)) {
                 /** @var array{0: non-empty-string, 1: string} $matches */
                 $protocol['FROM'][] = $matches[1];
@@ -48,19 +50,16 @@ public function dispatch(StreamClient $stream): iterable
             } elseif (\str_starts_with($response, 'QUIT')) {
                 $stream->sendData($this->createResponse(self::CLOSING));
                 $stream->disconnect();
+                return;
             } elseif (\str_starts_with($response, 'DATA')) {
                 $stream->sendData($this->createResponse(self::START_MAIL_INPUT));
-
                 $message = $this->parser->parseStream($protocol, $stream);
                 $stream->sendData($this->createResponse(self::OK));
+                yield new Frame\Smtp($message, $stream->getCreatedAt());
+                $protocol = [];
+                unset($message);
             }
         }
-
-        if ($message === null) {
-            return;
-        }
-
-        yield new Frame\Smtp($message, $stream->getCreatedAt());
     }
 
     public function detect(string $data, \DateTimeImmutable $createdAt): ?bool

src/Traffic/Message/Smtp.php

@@ -133,23 +133,23 @@
     {
         $addrs = \array_unique(\array_merge((array) ($this->protocol['FROM'] ?? []), $this->getHeader('From')));
 
-        return \array_map([$this, 'parseContact'], $addrs);
+        return \array_map(self::parseContact(...), $addrs);
     }
 
     /**
      * @return Contact[]
      */
     public function getTo(): array
     {
-        return $this->normalizeAddressList($this->getHeader('To'));
+        return self::normalizeAddressList($this->getHeader('To'));
     }
 
     /**
      * @return Contact[]
      */
     public function getCc(): array
     {
-        return $this->normalizeAddressList($this->getHeader('Cc'));
+        return self::normalizeAddressList($this->getHeader('Cc'));
     }
 
     /**
@@ -160,15 +160,15 @@
      */
     public function getBcc(): array
     {
-        return $this->normalizeAddressList($this->protocol['BCC'] ?? []);
+        return self::normalizeAddressList($this->protocol['BCC'] ?? []);
     }
 
     /**
      * @return Contact[]
      */
     public function getReplyTo(): array
     {
-        return $this->normalizeAddressList($this->getHeader('Reply-To'));
+        return self::normalizeAddressList($this->getHeader('Reply-To'));
     }
 
     public function getSubject(): string
@@ -187,7 +187,7 @@
         return null;
     }
 
-    private function parseContact(string $line): Contact
+    private static function parseContact(string $line): Contact
     {
         if (\preg_match('/^\s*+(?<name>.*?)\s*<(?<email>.*)>\s*$/', $line, $matches) === 1) {
             $name = match (true) {
@@ -206,26 +206,27 @@
     }
 
     /**
-     * @return array<Contact>
+     * @return list<Contact>
      */
-    private function parseDestinationAddress(string $line): array
+    private static function parseDestinationAddress(string $line): array
     {
         // if this is a group recipient
         if (\preg_match('/^[^"]+:(.*);$/', $line, $matches) === 1) {
             $line = $matches[1];
         }
 
-        $emailList = \array_map('trim', \explode(',', $line));
-        return \array_map([$this, 'parseContact'], $emailList);
+        $emailList = \array_map(\trim(...), \explode(',', $line));
+        return \array_map(self::parseContact(...), $emailList);
     }
 
     /**
-     * @return array<Contact>
+     * @param list<string> $param
+     * @return list<Contact>
      */
-    private function normalizeAddressList(array $param): array
+    private static function normalizeAddressList(array $param): array
     {
         return \array_merge(
-            ...\array_map([$this, 'parseDestinationAddress'], $param),
+            ...\array_map(self::parseDestinationAddress(...), $param),
         );
     }
 }

tests/Unit/Traffic/Dispatcher/SmtpTest.php

@@ -0,0 +1,110 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Buggregator\Trap\Tests\Unit\Traffic\Dispatcher;
+
+use Buggregator\Trap\Proto\Frame\Smtp as SmtpFrame;
+use Buggregator\Trap\Test\Mock\StreamClientMock;
+use Buggregator\Trap\Tests\Unit\FiberTrait;
+use Buggregator\Trap\Traffic\Dispatcher\Smtp;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\TestCase;
+
+#[CoversClass(Smtp::class)]
+class SmtpTest extends TestCase
+{
+    use FiberTrait;
+
+    public function testDispatchOneMail(): void
+    {
+        $stream = StreamClientMock::createFromGenerator($this->mailMe(quit: true));
+
+        $this->runInFiber(static function () use ($stream): void {
+            $cnt = 0;
+            foreach ((new Smtp())->dispatch($stream) as $frame) {
+                self::assertInstanceOf(SmtpFrame::class, $frame);
+                self::assertSame('Test email', $frame->message->getSubject());
+                ++$cnt;
+            }
+
+            self::assertSame(1, $cnt, 'Only one frame should be yielded.');
+        });
+    }
+
+    public function testDispatchOneMailWithRset(): void
+    {
+        $stream = StreamClientMock::createFromGenerator((function (\Generator ...$generators) {
+            yield "EHLO\r\n";
+            yield "MAIL FROM: <someusername@foo.bar>\r\n";
+            yield "RCPT TO: <user10@company.tld>\r\n";
+            yield "RCPT TO: <user22@company.tld>\r\n";
+            yield "RSET\r\n";
+            yield from $this->mailMe('Test email');
+        })());
+
+        $this->runInFiber(static function () use ($stream): void {
+            $cnt = 0;
+            foreach ((new Smtp())->dispatch($stream) as $frame) {
+                self::assertInstanceOf(SmtpFrame::class, $frame);
+                self::assertSame("Test email", $frame->message->getSubject());
+                self::assertSame(
+                    ['user1@company.tld', 'user2@company.tld'],
+                    $frame->message->getProtocol()['BCC'],
+                    'RSET should clear the buffered data.',
+                );
+                ++$cnt;
+            }
+
+            self::assertSame(1, $cnt, 'Only one frame should be yielded.');
+        });
+    }
+
+    public function testDispatchMultipleMails(): void
+    {
+        $stream = StreamClientMock::createFromGenerator((static function (\Generator ...$generators) {
+            foreach ($generators as $generator) {
+                yield from $generator;
+            }
+        })(
+            $this->mailMe('Test email 1'),
+            $this->mailMe('Test email 2'),
+            $this->mailMe('Test email 3'),
+        ));
+
+        $this->runInFiber(static function () use ($stream): void {
+            $i = 1;
+            foreach ((new Smtp())->dispatch($stream) as $frame) {
+                self::assertInstanceOf(SmtpFrame::class, $frame);
+                self::assertSame("Test email $i", $frame->message->getSubject());
+
+                if (++$i === 3) {
+                    return;
+                }
+            }
+
+            self::fail('No frame was yielded.');
+        });
+    }
+
+    private function mailMe(string $subject = 'Test email', bool $quit = false): \Generator
+    {
+        yield "EHLO\r\n";
+        yield "MAIL FROM: <someusername@foo.bar>\r\n";
+        yield "RCPT TO: <user1@company.tld>\r\n";
+        yield "RCPT TO: <user2@company.tld>\r\n";
+        yield "NOOP\r\n";
+        yield "DATA\r\n";
+        yield "From: sender@example.com\r\n";
+        yield "To: recipient@example.com\r\n";
+        yield "Subject: $subject\r\n";
+        yield "Content-Type: text/plain\r\n";
+        yield "\r\n";
+        yield "Hello, this is a test email.\r\n";
+        yield ".\r\n";
+        yield "NOOP\r\n";
+        if ($quit) {
+            yield "QUIT\r\n";
+        }
+    }
+}

tests/Unit/Traffic/Parser/SmtpParserTest.php

@@ -8,8 +8,10 @@
 use Buggregator\Trap\Tests\Unit\FiberTrait;
 use Buggregator\Trap\Traffic\Message;
 use Buggregator\Trap\Traffic\Parser;
+use PHPUnit\Framework\Attributes\CoversClass;
 use PHPUnit\Framework\TestCase;
 
+#[CoversClass(Parser\Smtp::class)]
 final class SmtpParserTest extends TestCase
 {
     use FiberTrait;