feat(ocp): add email address validator

Signed-off-by: Daniel Kesselberg <mail@danielkesselberg.de>

Author: kesselb

build/psalm-baseline.xml

@@ -371,6 +371,12 @@
     </UndefinedMethod>
   </file>
   <file src="apps/dav/lib/CalDAV/Reminder/NotificationProvider/EmailProvider.php">
+    <DeprecatedMethod>
+      <code><![CDATA[validateMailAddress]]></code>
+      <code><![CDATA[validateMailAddress]]></code>
+      <code><![CDATA[validateMailAddress]]></code>
+      <code><![CDATA[validateMailAddress]]></code>
+    </DeprecatedMethod>
     <LessSpecificReturnStatement>
       <code><![CDATA[$emailAddresses]]></code>
     </LessSpecificReturnStatement>
@@ -452,6 +458,9 @@
     </DeprecatedMethod>
   </file>
   <file src="apps/dav/lib/CalDAV/Schedule/IMipPlugin.php">
+    <DeprecatedMethod>
+      <code><![CDATA[validateMailAddress]]></code>
+    </DeprecatedMethod>
     <RedundantCast>
       <code><![CDATA[(string)$iTipMessage->recipientName]]></code>
     </RedundantCast>
@@ -864,6 +873,11 @@
       <code><![CDATA[getUserFolder]]></code>
     </DeprecatedMethod>
   </file>
+  <file src="apps/dav/lib/Listener/CalendarContactInteractionListener.php">
+    <DeprecatedMethod>
+      <code><![CDATA[validateMailAddress]]></code>
+    </DeprecatedMethod>
+  </file>
   <file src="apps/dav/lib/Migration/BuildCalendarSearchIndex.php">
     <DeprecatedMethod>
       <code><![CDATA[getAppValue]]></code>
@@ -1572,6 +1586,7 @@
     </DeprecatedClass>
     <DeprecatedMethod>
       <code><![CDATA[getAppValue]]></code>
+      <code><![CDATA[validateMailAddress]]></code>
     </DeprecatedMethod>
     <RedundantCast>
       <code><![CDATA[(int)$code]]></code>
@@ -2079,6 +2094,7 @@
       <code><![CDATA[getAppValue]]></code>
       <code><![CDATA[getAppValue]]></code>
       <code><![CDATA[setAppValue]]></code>
+      <code><![CDATA[validateMailAddress]]></code>
     </DeprecatedMethod>
   </file>
   <file src="apps/settings/lib/Controller/WebAuthnController.php">
@@ -2201,6 +2217,10 @@
     </DeprecatedMethod>
   </file>
   <file src="apps/sharebymail/lib/ShareByMailProvider.php">
+    <DeprecatedMethod>
+      <code><![CDATA[validateMailAddress]]></code>
+      <code><![CDATA[validateMailAddress]]></code>
+    </DeprecatedMethod>
     <InvalidArgument>
       <code><![CDATA[$share->getId()]]></code>
       <code><![CDATA[(int)$data['id']]]></code>
@@ -3053,6 +3073,11 @@
       <code><![CDATA[listen]]></code>
     </DeprecatedMethod>
   </file>
+  <file src="core/Command/User/Add.php">
+    <DeprecatedMethod>
+      <code><![CDATA[validateMailAddress]]></code>
+    </DeprecatedMethod>
+  </file>
   <file src="core/Command/User/AuthTokens/Add.php">
     <DeprecatedClass>
       <code><![CDATA[IToken::DO_NOT_REMEMBER]]></code>

lib/composer/composer/autoload_classmap.php

@@ -655,6 +655,7 @@
     'OCP\\Mail\\Headers\\AutoSubmitted' => $baseDir . '/lib/public/Mail/Headers/AutoSubmitted.php',
     'OCP\\Mail\\IAttachment' => $baseDir . '/lib/public/Mail/IAttachment.php',
     'OCP\\Mail\\IEMailTemplate' => $baseDir . '/lib/public/Mail/IEMailTemplate.php',
+    'OCP\\Mail\\IEmailValidator' => $baseDir . '/lib/public/Mail/IEmailValidator.php',
     'OCP\\Mail\\IMailer' => $baseDir . '/lib/public/Mail/IMailer.php',
     'OCP\\Mail\\IMessage' => $baseDir . '/lib/public/Mail/IMessage.php',
     'OCP\\Mail\\Provider\\Address' => $baseDir . '/lib/public/Mail/Provider/Address.php',
@@ -1820,6 +1821,7 @@
     'OC\\Log\\Systemdlog' => $baseDir . '/lib/private/Log/Systemdlog.php',
     'OC\\Mail\\Attachment' => $baseDir . '/lib/private/Mail/Attachment.php',
     'OC\\Mail\\EMailTemplate' => $baseDir . '/lib/private/Mail/EMailTemplate.php',
+    'OC\\Mail\\EmailValidator' => $baseDir . '/lib/private/Mail/EmailValidator.php',
     'OC\\Mail\\Mailer' => $baseDir . '/lib/private/Mail/Mailer.php',
     'OC\\Mail\\Message' => $baseDir . '/lib/private/Mail/Message.php',
     'OC\\Mail\\Provider\\Manager' => $baseDir . '/lib/private/Mail/Provider/Manager.php',

lib/composer/composer/autoload_static.php

@@ -696,6 +696,7 @@ class ComposerStaticInit749170dad3f5e7f9ca158f5a9f04f6a2
         'OCP\\Mail\\Headers\\AutoSubmitted' => __DIR__ . '/../../..' . '/lib/public/Mail/Headers/AutoSubmitted.php',
         'OCP\\Mail\\IAttachment' => __DIR__ . '/../../..' . '/lib/public/Mail/IAttachment.php',
         'OCP\\Mail\\IEMailTemplate' => __DIR__ . '/../../..' . '/lib/public/Mail/IEMailTemplate.php',
+        'OCP\\Mail\\IEmailValidator' => __DIR__ . '/../../..' . '/lib/public/Mail/IEmailValidator.php',
         'OCP\\Mail\\IMailer' => __DIR__ . '/../../..' . '/lib/public/Mail/IMailer.php',
         'OCP\\Mail\\IMessage' => __DIR__ . '/../../..' . '/lib/public/Mail/IMessage.php',
         'OCP\\Mail\\Provider\\Address' => __DIR__ . '/../../..' . '/lib/public/Mail/Provider/Address.php',
@@ -1861,6 +1862,7 @@ class ComposerStaticInit749170dad3f5e7f9ca158f5a9f04f6a2
         'OC\\Log\\Systemdlog' => __DIR__ . '/../../..' . '/lib/private/Log/Systemdlog.php',
         'OC\\Mail\\Attachment' => __DIR__ . '/../../..' . '/lib/private/Mail/Attachment.php',
         'OC\\Mail\\EMailTemplate' => __DIR__ . '/../../..' . '/lib/private/Mail/EMailTemplate.php',
+        'OC\\Mail\\EmailValidator' => __DIR__ . '/../../..' . '/lib/private/Mail/EmailValidator.php',
         'OC\\Mail\\Mailer' => __DIR__ . '/../../..' . '/lib/private/Mail/Mailer.php',
         'OC\\Mail\\Message' => __DIR__ . '/../../..' . '/lib/private/Mail/Message.php',
         'OC\\Mail\\Provider\\Manager' => __DIR__ . '/../../..' . '/lib/private/Mail/Provider/Manager.php',

lib/private/Mail/EmailValidator.php

@@ -0,0 +1,37 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OC\Mail;
+
+use Egulias\EmailValidator\EmailValidator as EquliasEmailValidator;
+use Egulias\EmailValidator\Validation\NoRFCWarningsValidation;
+use Egulias\EmailValidator\Validation\RFCValidation;
+use OCP\IAppConfig;
+use OCP\Mail\IEmailValidator;
+
+class EmailValidator implements IEmailValidator {
+	public function __construct(
+		private IAppConfig $appConfig,
+	) {
+	}
+
+	public function isValid(string $email): bool {
+		if ($email === '') {
+			// Shortcut: empty addresses are never valid
+			return false;
+		}
+
+		$strictMailCheck = $this->appConfig->getValueString('core', 'enforce_strict_email_check', 'yes') === 'yes';
+
+		$validator = new EquliasEmailValidator();
+		$validation = $strictMailCheck ? new NoRFCWarningsValidation() : new RFCValidation();
+
+		return $validator->isValid($email, $validation);
+	}
+}

lib/private/Mail/Mailer.php

@@ -8,9 +8,6 @@
  */
 namespace OC\Mail;
 
-use Egulias\EmailValidator\EmailValidator;
-use Egulias\EmailValidator\Validation\NoRFCWarningsValidation;
-use Egulias\EmailValidator\Validation\RFCValidation;
 use OCP\Defaults;
 use OCP\EventDispatcher\IEventDispatcher;
 use OCP\IBinaryFinder;
@@ -21,6 +18,7 @@
 use OCP\Mail\Events\BeforeMessageSent;
 use OCP\Mail\IAttachment;
 use OCP\Mail\IEMailTemplate;
+use OCP\Mail\IEmailValidator;
 use OCP\Mail\IMailer;
 use OCP\Mail\IMessage;
 use Psr\Log\LoggerInterface;
@@ -69,6 +67,7 @@ public function __construct(
 		private IL10N $l10n,
 		private IEventDispatcher $dispatcher,
 		private IFactory $l10nFactory,
+		private IEmailValidator $emailValidator,
 	) {
 	}
 
@@ -234,18 +233,10 @@ public function send(IMessage $message): array {
 	/**
 	 * @param string $email Email address to be validated
 	 * @return bool True if the mail address is valid, false otherwise
+	 * @deprecated 26.0.0 use IEmailValidator.isValid instead
 	 */
 	public function validateMailAddress(string $email): bool {
-		if ($email === '') {
-			// Shortcut: empty addresses are never valid
-			return false;
-		}
-
-		$strictMailCheck = $this->config->getAppValue('core', 'enforce_strict_email_check', 'yes') === 'yes';
-		$validator = new EmailValidator();
-		$validation = $strictMailCheck ? new NoRFCWarningsValidation() : new RFCValidation();
-
-		return $validator->isValid($email, $validation);
+		return $this->emailValidator->isValid($email);
 	}
 
 	protected function getInstance(): MailerInterface {

lib/private/Server.php

@@ -77,6 +77,7 @@
 use OC\Lockdown\LockdownManager;
 use OC\Log\LogFactory;
 use OC\Log\PsrLoggerAdapter;
+use OC\Mail\EmailValidator;
 use OC\Mail\Mailer;
 use OC\Memcache\ArrayCache;
 use OC\Memcache\Factory;
@@ -195,6 +196,7 @@
 use OCP\Lock\ILockingProvider;
 use OCP\Lockdown\ILockdownManager;
 use OCP\Log\ILogFactory;
+use OCP\Mail\IEmailValidator;
 use OCP\Mail\IMailer;
 use OCP\OCM\ICapabilityAwareOCMProvider;
 use OCP\OCM\IOCMDiscoveryService;
@@ -916,6 +918,9 @@ public function __construct($webRoot, \OC\Config $config) {
 			);
 		});
 
+		/** @since 32.0.0 */
+		$this->registerAlias(IEmailValidator::class, EmailValidator::class);
+
 		$this->registerService(IMailer::class, function (Server $c) {
 			return new Mailer(
 				$c->get(\OCP\IConfig::class),
@@ -924,7 +929,8 @@ public function __construct($webRoot, \OC\Config $config) {
 				$c->get(IURLGenerator::class),
 				$c->getL10N('lib'),
 				$c->get(IEventDispatcher::class),
-				$c->get(IFactory::class)
+				$c->get(IFactory::class),
+				$c->get(IEmailValidator::class),
 			);
 		});
 

lib/public/Mail/IEmailValidator.php

@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCP\Mail;
+
+/**
+ * Validator for email addresses
+ *
+ * @since 32.0.0
+ */
+interface IEmailValidator {
+	/**
+	 * @param string $email Email address to be validated
+	 * @return bool True if the mail address is valid, false otherwise
+	 * @since 32.0.0
+	 */
+	public function isValid(string $email): bool;
+}

lib/public/Mail/IMailer.php

@@ -80,6 +80,7 @@ public function send(IMessage $message): array;
 	 * @param string $email Email address to be validated
 	 * @return bool True if the mail address is valid, false otherwise
 	 * @since 8.1.0
+	 * @deprecated 26.0.0 use IEmailValidator.isValid instead
 	 */
 	public function validateMailAddress(string $email): bool;
 }

tests/lib/Mail/EmailValidatorTest.php

@@ -0,0 +1,53 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace Test\Mail;
+
+use OC\Mail\EmailValidator;
+use OCP\IAppConfig;
+use PHPUnit\Framework\Attributes\DataProvider;
+use PHPUnit\Framework\MockObject\MockObject;
+use Test\TestCase;
+
+class EmailValidatorTest extends TestCase {
+	private IAppConfig&MockObject $appConfig;
+	private EmailValidator $emailValidator;
+
+
+	protected function setUp(): void {
+		parent::setUp();
+
+		$this->appConfig = $this->createMock(IAppConfig::class);
+		$this->emailValidator = new EmailValidator($this->appConfig);
+	}
+
+	public static function mailAddressProvider(): array {
+		return [
+			['lukas@nextcloud.com', true, false],
+			['lukas@localhost', true, false],
+			['lukas@192.168.1.1', true, false],
+			['lukas@éxämplè.com', true, false],
+			['asdf', false, false],
+			['', false, false],
+			['lukas@nextcloud.org@nextcloud.com', false, false],
+			['test@localhost', true, false],
+			['test@localhost', false, true],
+		];
+	}
+
+	#[DataProvider('mailAddressProvider')]
+	public function testIsValid($email, $expected, $strict): void {
+		$this->appConfig
+			->expects($this->atMost(1))
+			->method('getValueString')
+			->with('core', 'enforce_strict_email_check', 'yes')
+			->willReturn($strict ? 'yes' : 'no');
+		$this->assertSame($expected, $this->emailValidator->isValid($email));
+	}
+}

tests/lib/Mail/MailerTest.php

@@ -19,6 +19,7 @@
 use OCP\IURLGenerator;
 use OCP\L10N\IFactory;
 use OCP\Mail\Events\BeforeMessageSent;
+use OCP\Mail\IEmailValidator;
 use OCP\Server;
 use PHPUnit\Framework\MockObject\MockObject;
 use Psr\Log\LoggerInterface;
@@ -61,7 +62,8 @@ protected function setUp(): void {
 			$this->urlGenerator,
 			$this->l10n,
 			$this->dispatcher,
-			$this->createMock(IFactory::class)
+			$this->createMock(IFactory::class),
+			$this->createMock(IEmailValidator::class),
 		);
 	}
 
@@ -181,7 +183,8 @@ public function testEvents(): void {
 					$this->urlGenerator,
 					$this->l10n,
 					$this->dispatcher,
-					$this->createMock(IFactory::class)
+					$this->createMock(IFactory::class),
+					$this->createMock(IEmailValidator::class),
 				]
 			)
 			->getMock();
@@ -226,33 +229,6 @@ public function testSendInvalidMailException(): void {
 		$this->mailer->send($message);
 	}
 
-	/**
-	 * @return array
-	 */
-	public static function mailAddressProvider(): array {
-		return [
-			['lukas@owncloud.com', true, false],
-			['lukas@localhost', true, false],
-			['lukas@192.168.1.1', true, false],
-			['lukas@éxämplè.com', true, false],
-			['asdf', false, false],
-			['', false, false],
-			['lukas@owncloud.org@owncloud.com', false, false],
-			['test@localhost', true, false],
-			['test@localhost', false, true],
-		];
-	}
-
-	#[\PHPUnit\Framework\Attributes\DataProvider('mailAddressProvider')]
-	public function testValidateMailAddress($email, $expected, $strict): void {
-		$this->config
-			->expects($this->atMost(1))
-			->method('getAppValue')
-			->with('core', 'enforce_strict_email_check')
-			->willReturn($strict ? 'yes' : 'no');
-		$this->assertSame($expected, $this->mailer->validateMailAddress($email));
-	}
-
 	public function testCreateEMailTemplate(): void {
 		$this->config->method('getSystemValueString')
 			->with('mail_template_class', '')