feat(Mailer): add "null" SMTP transport mode

== Goal

Allow disabling mail delivery altogether.

== Usecase

If mails ought to be send by other means than rendering messages from
templates and sending them via SMTP-like protocols.

Example: listening to specific Nextcloud events and pass parameters to
a centralized (i.e. REST-based) API that sends e-mails.

Signed-off-by: Thomas Lehmann <t.lehmann@strato.de>

1 files changed, 4 insertions, 0 deletions

diff --git a/lib/private/Mail/Mailer.php b/lib/private/Mail/Mailer.php
index b660ee0c02f..18636e183d0 100644
--- a/lib/private/Mail/Mailer.php
+++ b/lib/private/Mail/Mailer.php
@@ -27,6 +27,7 @@ use Psr\Log\LoggerInterface;
 use Symfony\Component\Mailer\Exception\TransportExceptionInterface;
 use Symfony\Component\Mailer\Mailer as SymfonyMailer;
 use Symfony\Component\Mailer\MailerInterface;
+use Symfony\Component\Mailer\Transport\NullTransport;
 use Symfony\Component\Mailer\Transport\SendmailTransport;
 use Symfony\Component\Mailer\Transport\Smtp\EsmtpTransport;
 use Symfony\Component\Mailer\Transport\Smtp\Stream\SocketStream;
@@ -256,6 +257,9 @@ class Mailer implements IMailer {
 		}
 
 		switch ($this->config->getSystemValueString('mail_smtpmode', 'smtp')) {
+			case 'null':
+				$transport = new NullTransport();
+				break;
 			case 'sendmail':
 				$transport = $this->getSendMailInstance();
 				break;