add FallbackMailer

src/Mail/FallbackMailer.php

@@ -0,0 +1,132 @@
+<?php
+
+/**
+ * This file is part of the Nette Framework (https://nette.org)
+ * Copyright (c) 2004 David Grudl (https://davidgrudl.com)
+ */
+
+namespace Nette\Mail;
+
+use Nette;
+use Nette\InvalidArgumentException;
+
+
+class FallbackMailer implements IMailer
+{
+	use Nette\SmartObject;
+
+	/** @var callable[]  function (FallbackMailer $sender, SendException $e, IMailer $mailer, Message $mail) */
+	public $onFailure;
+
+	/** @var IMailer[] */
+	private $mailers;
+
+	/** @var int */
+	private $retryCount;
+
+	/** @var int in miliseconds */
+	private $retryWaitTime;
+
+
+	/**
+	 * @param IMailer[]
+	 * @param int
+	 * @param int in miliseconds
+	 */
+	public function __construct(array $mailers, $retryCount = 3, $retryWaitTime = 1000)
+	{
+		if (!$mailers) {
+			throw new InvalidArgumentException('At least one mailer must be provided.');
+		}
+
+		$this->mailers = $mailers;
+		$this->retryCount = $retryCount;
+		$this->retryWaitTime = $retryWaitTime;
+	}
+
+
+	/**
+	 * Sends email.
+	 * @return void
+	 * @throws FallbackMailerException
+	 */
+	public function send(Message $mail)
+	{
+		for ($i = 0; $i < $this->retryCount; $i++) {
+			if ($i > 0) {
+				usleep($this->retryWaitTime * 1000);
+			}
+
+			foreach ($this->mailers as $mailer) {
+				try {
+					$mailer->send($mail);
+					return;
+
+				} catch (SendException $e) {
+					$failures[] = $e;
+					$this->onFailure($this, $e, $mailer, $mail);
+				}
+			}
+		}
+
+		$e = new FallbackMailerException('All mailers failed to send the message.', 0, $failures[0]);
+		$e->failures = $failures;
+		throw $e;
+	}
+
+
+	/**
+	 * @return IMailer[]
+	 */
+	public function getMailers()
+	{
+		return $this->mailers;
+	}
+
+
+	/**
+	 * @param  IMailer[]
+	 * @return self
+	 */
+	public function addMailer(IMailer $mailer)
+	{
+		$this->mailers[] = $mailer;
+	}
+
+
+	/**
+	 * @return int
+	 */
+	public function getRetryCount()
+	{
+		return $this->retryCount;
+	}
+
+
+	/**
+	 * @param int
+	 */
+	public function setRetryCount($retryCount)
+	{
+		$this->retryCount = $retryCount;
+	}
+
+
+	/**
+	 * @return int in miliseconds
+	 */
+	public function getRetryWaitTime()
+	{
+		return $this->retryWaitTime;
+	}
+
+
+	/**
+	 * @param int in miliseconds
+	 */
+	public function setRetryWaitTime($retryWaitTime)
+	{
+		$this->retryWaitTime = $retryWaitTime;
+	}
+
+}

src/Mail/exceptions.php

@@ -24,3 +24,10 @@ class SendException extends Nette\InvalidStateException
 class SmtpException extends SendException
 {
 }
+
+
+class FallbackMailerException extends SendException
+{
+	/** @var SendException[] */
+	public $failures;
+}

tests/Mail/FallbackMailer.phpt

@@ -0,0 +1,88 @@
+<?php
+
+/**
+ * Test: Nette\Mail\FallbackMailer
+ */
+
+use Nette\Mail\FallbackMailer;
+use Nette\Mail\FallbackMailerException;
+use Nette\Mail\IMailer;
+use Nette\Mail\Message;
+use Nette\Mail\SendException;
+use Tester\Assert;
+
+
+require __DIR__ . '/../bootstrap.php';
+
+require __DIR__ . '/Mail.php';
+
+
+class FailingMailer implements IMailer
+{
+	private $failedTimes;
+
+
+	public function __construct($failedTimes)
+	{
+		$this->failedTimes = $failedTimes;
+	}
+
+
+	public function send(Message $mail)
+	{
+		static $count = 0;
+		if ($this->failedTimes--) {
+			throw new SendException('Failure #' . (++$count));
+		}
+	}
+}
+
+
+$send = function () {
+	$message = new Message();
+	$this->send($message);
+};
+
+
+test(function () use ($send) {
+	$subMailerA = new FailingMailer(3);
+	$subMailerB = new FailingMailer(3);
+
+	$mailer = new FallbackMailer([$subMailerA, $subMailerB], 3, 10);
+	$mailer->onFailure[] = function (FallbackMailer $sender, SendException $e, IMailer $mailer, Message $mail) use (& $onFailureCalls) {
+		$onFailureCalls[] = $mailer;
+	};
+
+	$e = Assert::exception($send->bindTo($mailer), FallbackMailerException::class, 'All mailers failed to send the message.');
+	Assert::same([$subMailerA, $subMailerB, $subMailerA, $subMailerB, $subMailerA, $subMailerB], $onFailureCalls);
+	Assert::count(6, $e->failures);
+	Assert::same('Failure #1', $e->getPrevious()->getMessage());
+});
+
+
+test(function () use ($send) {
+	$subMailerA = new FailingMailer(3);
+	$subMailerB = new FailingMailer(2);
+
+	$mailer = new FallbackMailer([$subMailerA, $subMailerB], 3, 10);
+	$mailer->onFailure[] = function (FallbackMailer $sender, SendException $e, IMailer $mailer, Message $mail) use (& $onFailureCalls) {
+		$onFailureCalls[] = $mailer;
+	};
+
+	$send->bindTo($mailer)->__invoke();
+	Assert::same([$subMailerA, $subMailerB, $subMailerA, $subMailerB, $subMailerA], $onFailureCalls);
+});
+
+
+test(function () use ($send) {
+	$subMailerA = new FailingMailer(0);
+	$subMailerB = new FailingMailer(2);
+
+	$mailer = new FallbackMailer([$subMailerA, $subMailerB], 3, 10);
+	$mailer->onFailure[] = function (FallbackMailer $sender, SendException $e, IMailer $mailer, Message $mail) use (& $onFailureCalls) {
+		$onFailureCalls[] = $mailer;
+	};
+
+	$send->bindTo($mailer)->__invoke();
+	Assert::null($onFailureCalls);
+});

tests/bootstrap.php

@@ -11,3 +11,9 @@
 
 Tester\Environment::setup();
 date_default_timezone_set('Europe/Prague');
+
+
+function test(\Closure $function)
+{
+	$function();
+}