Adding API method to set the Auto-Submitted header to OCP\Mail\IMessage

and implementation in OC\Mail\Message

Signed-off-by: Bennet Becker <bbecker@pks.mpg.de>

lib/private/Mail/Message.php

@@ -31,6 +31,7 @@ declare(strict_types=1);
  */
 namespace OC\Mail;
 
+use OCP\Mail\AutoSubmittedValue;
 use OCP\Mail\IAttachment;
 use OCP\Mail\IEMailTemplate;
 use OCP\Mail\IMessage;
@@ -301,4 +302,36 @@ class Message implements IMessage {
 		}
 		return $this;
 	}
+
+	/**
+	 * Add the Auto-Submitted header to the email, preventing most automated
+	 * responses to automated messages.
+	 *
+	 * @param string $value (one of AutoSubmittedValue::NO, AutoSubmittedValue::AUTO_GENERATED, AutoSubmittedValue::AUTO_REPLIED)
+	 * @return $this
+	 */
+	public function setAutoSubmitted(string $value): IMessage {
+		$headers = $this->swiftMessage->getHeaders();
+		if($headers->has('Auto-Submitted')) {
+			$auto_submitted = $headers->get('Auto-Submitted');
+			$auto_submitted->setValue($value);
+		} else {
+			$headers->addTextHeader('Auto-Submitted', $value);
+		}
+
+		return $this;
+	}
+
+	/**
+	 * Get the current value of the Auto-Submitted header. Defaults to "no"
+	 * which is equivalent to the header not existing at all
+	 *
+	 * @return string
+	 */
+	public function getAutoSubmitted(): AutoSubmittedValue {
+		$headers = $this->swiftMessage->getHeaders();
+
+		return $headers->has('Auto-Submitted') ?
+			$headers->get('Auto-Submitted')->toString() : "no";
+	}
 }

lib/public/Mail/AutoSubmittedValue.php

@@ -0,0 +1,66 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright Copyright (c) 2022 Bennet Becker <dev@bennet.cc>
+ *
+ * @author Bennet Becker <dev@bennet.cc>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+namespace OCP\Mail;
+
+/**
+ * Keyword values for the Auto-Submitted email header, as per RFC 3834.
+ *
+ * The value "auto-notified" as per RFC 5436 is deliberately omitted as it is
+ * meant of notification of the sieve system.
+ *
+ * @see https://www.iana.org/assignments/auto-submitted-keywords/auto-submitted-keywords.xhtml
+ *
+ * @since 26.0.0
+ */
+final class AutoSubmittedValue {
+	/**
+	 * Indicates that a message was NOT automatically generated, but was
+	 * created by a human (or following human interaction). It is the equivalent
+	 * to the absence of an Auto-Submitted header altogether.
+	 *
+	 * @var string
+	 * @since 26.0.0
+	 */
+	public const NO = 'no';
+
+	/**
+	 * Indicates that a message was generated by an automatic process, and is
+	 * not a direct response to another message
+	 *
+	 * @var string
+	 * @since 26.0.0
+	 */
+	public const AUTO_GENERATED = 'auto-generated';
+
+	/**
+	 * Indicates that a message was automatically generated as a direct response
+	 * to another message.
+	 *
+	 * @var string
+	 * @since 26.0.0
+	 */
+	public const AUTO_REPLIED = 'auto-replied';
+}

lib/public/Mail/IMessage.php

@@ -93,4 +93,14 @@ interface IMessage {
 	 * @since 13.0.0
 	 */
 	public function useTemplate(IEMailTemplate $emailTemplate): IMessage;
+
+	/**
+	 * Add the Auto-Submitted header to the email, preventing most automated
+	 * responses to automated messages.
+	 *
+	 * @param string $value (one of AutoSubmittedValue::NO, AutoSubmittedValue::AUTO_GENERATED, AutoSubmittedValue::AUTO_REPLIED)
+	 * @return IMessage
+	 * @since 26.0.0
+	 */
+	public function setAutoSubmitted(string $value): IMessage;
 }