Add Mattermost notifier bridge

Author: thePanz

DependencyInjection/FrameworkExtension.php

@@ -90,6 +90,7 @@
 use Symfony\Component\Messenger\Transport\TransportInterface;
 use Symfony\Component\Mime\MimeTypeGuesserInterface;
 use Symfony\Component\Mime\MimeTypes;
+use Symfony\Component\Notifier\Bridge\Mattermost\MattermostTransportFactory;
 use Symfony\Component\Notifier\Bridge\Nexmo\NexmoTransportFactory;
 use Symfony\Component\Notifier\Bridge\Slack\SlackTransportFactory;
 use Symfony\Component\Notifier\Bridge\Telegram\TelegramTransportFactory;
@@ -1997,6 +1998,7 @@ private function registerNotifierConfiguration(array $config, ContainerBuilder $
         $classToServices = [
             SlackTransportFactory::class => 'notifier.transport_factory.slack',
             TelegramTransportFactory::class => 'notifier.transport_factory.telegram',
+            MattermostTransportFactory::class => 'notifier.transport_factory.mattermost',
             NexmoTransportFactory::class => 'notifier.transport_factory.nexmo',
             TwilioTransportFactory::class => 'notifier.transport_factory.twilio',
         ];

Resources/config/notifier_transports.xml

@@ -18,6 +18,10 @@
             <tag name="chatter.transport_factory" />
         </service>
 
+        <service id="notifier.transport_factory.mattermost" class="Symfony\Component\Notifier\Bridge\Mattermost\MattermostTransportFactory" parent="notifier.transport_factory.abstract">
+            <tag name="chatter.transport_factory" />
+        </service>
+
         <service id="notifier.transport_factory.nexmo" class="Symfony\Component\Notifier\Bridge\Nexmo\NexmoTransportFactory" parent="notifier.transport_factory.abstract">
             <tag name="texter.transport_factory" />
         </service>