<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <[email protected]>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\Mailer\Transport\Smtp;
use Psr\EventDispatcher\EventDispatcherInterface;
use Psr\Log\LoggerInterface;
use Symfony\Component\Mailer\Envelope;
use Symfony\Component\Mailer\Exception\LogicException;
use Symfony\Component\Mailer\Exception\TransportException;
use Symfony\Component\Mailer\Exception\TransportExceptionInterface;
use Symfony\Component\Mailer\SentMessage;
use Symfony\Component\Mailer\Transport\AbstractTransport;
use Symfony\Component\Mailer\Transport\Smtp\Stream\AbstractStream;
use Symfony\Component\Mailer\Transport\Smtp\Stream\SocketStream;
use Symfony\Component\Mime\RawMessage;
/**
* Sends emails over SMTP.
*
* @author Fabien Potencier <[email protected]>
* @author Chris Corbyn
*/
class SmtpTransport extends AbstractTransport
{
private bool $started = false;
private int $restartThreshold = 100;
private int $restartThresholdSleep = 0;
private int $restartCounter = 0;
private int $pingThreshold = 100;
private float $lastMessageTime = 0;
private $stream;
private string $domain = '[127.0.0.1]';
public function __construct(AbstractStream $stream = null, EventDispatcherInterface $dispatcher = null, LoggerInterface $logger = null)
{
parent::__construct($dispatcher, $logger);
$this->stream = $stream ?? new SocketStream();
}
public function getStream(): AbstractStream
{
return $this->stream;
}
/**
* Sets the maximum number of messages to send before re-starting the transport.
*
* By default, the threshold is set to 100 (and no sleep at restart).
*
* @param int $threshold The maximum number of messages (0 to disable)
* @param int $sleep The number of seconds to sleep between stopping and re-starting the transport
*
* @return $this
*/
public function setRestartThreshold(int $threshold, int $sleep = 0): static
{
$this->restartThreshold = $threshold;
$this->restartThresholdSleep = $sleep;
return $this;
}
/**
* Sets the minimum number of seconds required between two messages, before the server is pinged.
* If the transport wants to send a message and the time since the last message exceeds the specified threshold,
* the transport will ping the server first (NOOP command) to check if the connection is still alive.
* Otherwise the message will be sent without pinging the server first.
*
* Do not set the threshold too low, as the SMTP server may drop the connection if there are too many
* non-mail commands (like pinging the server with NOOP).
*
* By default, the threshold is set to 100 seconds.
*
* @param int $seconds The minimum number of seconds between two messages required to ping the server
*
* @return $this
*/
public function setPingThreshold(int $seconds): static
{
$this->pingThreshold = $seconds;
return $this;
}
/**
* Sets the name of the local domain that will be used in HELO.
*
* This should be a fully-qualified domain name and should be truly the domain
* you're using.
*
* If your server does not have a domain name, use the IP address. This will
* automatically be wrapped in square brackets as described in RFC 5321,
* section 4.1.3.
*
* @return $this
*/
public function setLocalDomain(string $domain): static
{
if ('' !== $domain && '[' !== $domain[0]) {
if (filter_var($domain, \FILTER_VALIDATE_IP, \FILTER_FLAG_IPV4)) {
$domain = '['.$domain.']';
} elseif (filter_var($domain, \FILTER_VALIDATE_IP, \FILTER_FLAG_IPV6)) {
$domain = '[IPv6:'.$domain.']';
}
}
$this->domain = $domain;
return $this;
}
/**
* Gets the name of the domain that will be used in HELO.
*
* If an IP address was specified, this will be returned wrapped in square
* brackets as described in RFC 5321, section 4.1.3.
*/
public function getLocalDomain(): string
{
return $this->domain;
}
public function send(RawMessage $message, Envelope $envelope = null): ?SentMessage
{
try {
$message = parent::send($message, $envelope);
} catch (TransportExceptionInterface $e) {
if ($this->started) {
try {
$this->executeCommand("RSET\r\n", [250]);
} catch (TransportExceptionInterface $_) {
// ignore this exception as it probably means that the server error was final
}
}
throw $e;
}
$this->checkRestartThreshold();
return $message;
}
public function __toString(): string
{
if ($this->stream instanceof SocketStream) {
$name = sprintf('smtp%s://%s', ($tls = $this->stream->isTLS()) ? 's' : '', $this->stream->getHost());
$port = $this->stream->getPort();
if (!(25 === $port || ($tls && 465 === $port))) {
$name .= ':'.$port;
}
return $name;
}
return 'smtp://sendmail';
}
/**
* Runs a command against the stream, expecting the given response codes.
*
* @param int[] $codes
*
* @throws TransportException when an invalid response if received
*
* @internal
*/
public function executeCommand(string $command, array $codes): string
{
$this->stream->write($command);
$response = $this->getFullResponse();
$this->assertResponseCode($response, $codes);
return $response;
}
protected function doSend(SentMessage $message): void
{
if (microtime(true) - $this->lastMessageTime > $this->pingThreshold) {
$this->ping();
}
if (!$this->started) {
$this->start();
}
try {
$envelope = $message->getEnvelope();
$this->doMailFromCommand($envelope->getSender()->getEncodedAddress());
foreach ($envelope->getRecipients() as $recipient) {
$this->doRcptToCommand($recipient->getEncodedAddress());
}
$this->executeCommand("DATA\r\n", [354]);
try {
foreach (AbstractStream::replace("\r\n.", "\r\n..", $message->toIterable()) as $chunk) {
$this->stream->write($chunk, false);
}
$this->stream->flush();
} catch (TransportExceptionInterface $e) {
throw $e;
} catch (\Exception $e) {
$this->stream->terminate();
$this->started = false;
$this->getLogger()->debug(sprintf('Email transport "%s" stopped', __CLASS__));
throw $e;
}
$this->executeCommand("\r\n.\r\n", [250]);
$message->appendDebug($this->stream->getDebug());
$this->lastMessageTime = microtime(true);
} catch (TransportExceptionInterface $e) {
$e->appendDebug($this->stream->getDebug());
$this->lastMessageTime = 0;
throw $e;
}
}
protected function doHeloCommand(): void
{
$this->executeCommand(sprintf("HELO %s\r\n", $this->domain), [250]);
}
private function doMailFromCommand(string $address): void
{
$this->executeCommand(sprintf("MAIL FROM:<%s>\r\n", $address), [250]);
}
private function doRcptToCommand(string $address): void
{
$this->executeCommand(sprintf("RCPT TO:<%s>\r\n", $address), [250, 251, 252]);
}
private function start(): void
{
if ($this->started) {
return;
}
$this->getLogger()->debug(sprintf('Email transport "%s" starting', __CLASS__));
$this->stream->initialize();
$this->assertResponseCode($this->getFullResponse(), [220]);
$this->doHeloCommand();
$this->started = true;
$this->lastMessageTime = 0;
$this->getLogger()->debug(sprintf('Email transport "%s" started', __CLASS__));
}
private function stop(): void
{
if (!$this->started) {
return;
}
$this->getLogger()->debug(sprintf('Email transport "%s" stopping', __CLASS__));
try {
$this->executeCommand("QUIT\r\n", [221]);
} catch (TransportExceptionInterface $e) {
} finally {
$this->stream->terminate();
$this->started = false;
$this->getLogger()->debug(sprintf('Email transport "%s" stopped', __CLASS__));
}
}
private function ping(): void
{
if (!$this->started) {
return;
}
try {
$this->executeCommand("NOOP\r\n", [250]);
} catch (TransportExceptionInterface $e) {
$this->stop();
}
}
/**
* @throws TransportException if a response code is incorrect
*/
private function assertResponseCode(string $response, array $codes): void
{
if (!$codes) {
throw new LogicException('You must set the expected response code.');
}
[$code] = sscanf($response, '%3d');
$valid = \in_array($code, $codes);
if (!$valid || !$response) {
$codeStr = $code ? sprintf('code "%s"', $code) : 'empty code';
$responseStr = $response ? sprintf(', with message "%s"', trim($response)) : '';
throw new TransportException(sprintf('Expected response code "%s" but got ', implode('/', $codes)).$codeStr.$responseStr.'.', $code ?: 0);
}
}
private function getFullResponse(): string
{
$response = '';
do {
$line = $this->stream->readLine();
$response .= $line;
} while ($line && isset($line[3]) && ' ' !== $line[3]);
return $response;
}
private function checkRestartThreshold(): void
{
// when using sendmail via non-interactive mode, the transport is never "started"
if (!$this->started) {
return;
}
++$this->restartCounter;
if ($this->restartCounter < $this->restartThreshold) {
return;
}
$this->stop();
if (0 < $sleep = $this->restartThresholdSleep) {
$this->getLogger()->debug(sprintf('Email transport "%s" sleeps for %d seconds after stopping', __CLASS__, $sleep));
sleep($sleep);
}
$this->start();
$this->restartCounter = 0;
}
public function __sleep(): array
{
throw new \BadMethodCallException('Cannot serialize '.__CLASS__);
}
public function __wakeup()
{
throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
}
public function __destruct()
{
$this->stop();
}
}