feat(settings): Migrate .well-known URL setup check to new API

Co-authored-by: Côme Chilliet <come.chilliet@nextcloud.com>
Co-authored-by: Ferdinand Thiessen <opensource@fthiessen.de>
Signed-off-by: Ferdinand Thiessen <opensource@fthiessen.de>

3 files changed, 142 insertions, 6 deletions

diff --git a/apps/settings/lib/AppInfo/Application.php b/apps/settings/lib/AppInfo/Application.php
index 12cd21cf17c..0977da398b0 100644
--- a/apps/settings/lib/AppInfo/Application.php
+++ b/apps/settings/lib/AppInfo/Application.php
@@ -90,6 +90,7 @@ use OCA\Settings\SetupChecks\SupportedDatabase;
 use OCA\Settings\SetupChecks\SystemIs64bit;
 use OCA\Settings\SetupChecks\TempSpaceAvailable;
 use OCA\Settings\SetupChecks\TransactionIsolation;
+use OCA\Settings\SetupChecks\WellKnownUrls;
 use OCA\Settings\SetupChecks\Woff2Loading;
 use OCA\Settings\UserMigration\AccountMigrator;
 use OCA\Settings\WellKnown\ChangePasswordHandler;
@@ -218,6 +219,7 @@ class Application extends App implements IBootstrap {
 		$context->registerSetupCheck(TempSpaceAvailable::class);
 		$context->registerSetupCheck(TransactionIsolation::class);
 		$context->registerSetupCheck(PushService::class);
+		$context->registerSetupCheck(WellKnownUrls::class);
 		$context->registerSetupCheck(Woff2Loading::class);
 
 		$context->registerUserMigrator(AccountMigrator::class);
diff --git a/apps/settings/lib/SetupChecks/CheckServerResponseTrait.php b/apps/settings/lib/SetupChecks/CheckServerResponseTrait.php
index bc757d27e48..aafade1526a 100644
--- a/apps/settings/lib/SetupChecks/CheckServerResponseTrait.php
+++ b/apps/settings/lib/SetupChecks/CheckServerResponseTrait.php
@@ -31,6 +31,7 @@ use OCP\Http\Client\IResponse;
 use OCP\IConfig;
 use OCP\IL10N;
 use OCP\IURLGenerator;
+use Psr\Log\LoggerInterface;
 
 /**
  * Common trait for setup checks that need to use requests to the same server and check the response
@@ -40,6 +41,7 @@ trait CheckServerResponseTrait {
 	protected IURLGenerator $urlGenerator;
 	protected IClientService $clientService;
 	protected IL10N $l10n;
+	protected LoggerInterface $logger;
 
 	/**
 	 * Common helper string in case a check could not fetch any results
@@ -71,25 +73,46 @@ trait CheckServerResponseTrait {
 	}
 
 	/**
-	 * Run a HEAD request to check header
+	 * Run a HTTP request to check header
 	 * @param string $url The relative URL to check
-	 * @param bool $ignoreSSL Ignore SSL certificates
-	 * @param bool $httpErrors Ignore requests with HTTP errors (will not yield if request has a 4xx or 5xx response)
+	 * @param string $method The HTTP method to use
+	 * @param array{ignoreSSL?: bool, httpErrors?: bool, options?: array} $options Additional options, like
+	 *                                                 [
+	 *                                                  // Ignore invalid SSL certificates (e.g. self signed)
+	 *                                                  'ignoreSSL' => true,
+	 *                                                  // Ignore requests with HTTP errors (will not yield if request has a 4xx or 5xx response)
+	 *                                                  'httpErrors' => true,
+	 *                                                 ]
+	 *
 	 * @return Generator<int, IResponse>
 	 */
-	protected function runHEAD(string $url, bool $ignoreSSL = true, bool $httpErrors = true): Generator {
+	protected function runRequest(string $url, string $method, array $options = []): Generator {
+		$options = array_merge(['ignoreSSL' => true, 'httpErrors' => true], $options);
+
 		$client = $this->clientService->newClient();
-		$requestOptions = $this->getRequestOptions($ignoreSSL, $httpErrors);
+		$requestOptions = $this->getRequestOptions($options['ignoreSSL'], $options['httpErrors']);
+		$requestOptions = array_merge($requestOptions, $options['options'] ?? []);
 
 		foreach ($this->getTestUrls($url) as $testURL) {
 			try {
-				yield $client->head($testURL, $requestOptions);
+				yield $client->request($testURL, $method, $requestOptions);
 			} catch (\Throwable $e) {
 				$this->logger->debug('Can not connect to local server for running setup checks', ['exception' => $e, 'url' => $testURL]);
 			}
 		}
 	}
 
+	/**
+	 * Run a HEAD request to check header
+	 * @param string $url The relative URL to check
+	 * @param bool $ignoreSSL Ignore SSL certificates
+	 * @param bool $httpErrors Ignore requests with HTTP errors (will not yield if request has a 4xx or 5xx response)
+	 * @return Generator<int, IResponse>
+	 */
+	protected function runHEAD(string $url, bool $ignoreSSL = true, bool $httpErrors = true): Generator {
+		return $this->runRequest($url, 'HEAD', ['ignoreSSL' => $ignoreSSL, 'httpErrors' => $httpErrors]);
+	}
+
 	protected function getRequestOptions(bool $ignoreSSL, bool $httpErrors): array {
 		$requestOptions = [
 			'connect_timeout' => 10,
diff --git a/apps/settings/lib/SetupChecks/WellKnownUrls.php b/apps/settings/lib/SetupChecks/WellKnownUrls.php
new file mode 100644
index 00000000000..933f82b614f
--- /dev/null
+++ b/apps/settings/lib/SetupChecks/WellKnownUrls.php
@@ -0,0 +1,111 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright Copyright (c) 2024 Côme Chilliet <come.chilliet@nextcloud.com>
+ *
+ * @author Côme Chilliet <come.chilliet@nextcloud.com>
+ * @author Ferdinand Thiessen <opensource@fthiessen.de>
+ *
+ * @license AGPL-3.0-or-later
+ *
+ * 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 OCA\Settings\SetupChecks;
+
+use OCP\Http\Client\IClientService;
+use OCP\IConfig;
+use OCP\IL10N;
+use OCP\IURLGenerator;
+use OCP\SetupCheck\ISetupCheck;
+use OCP\SetupCheck\SetupResult;
+use Psr\Log\LoggerInterface;
+
+class WellKnownUrls implements ISetupCheck {
+
+	use CheckServerResponseTrait;
+
+	public function __construct(
+		protected IL10N $l10n,
+		protected IConfig $config,
+		protected IURLGenerator $urlGenerator,
+		protected IClientService $clientService,
+		protected LoggerInterface $logger,
+	) {
+	}
+
+	public function getCategory(): string {
+		return 'network';
+	}
+
+	public function getName(): string {
+		return $this->l10n->t('.well-known URLs');
+	}
+
+	public function run(): SetupResult {
+		if (!$this->config->getSystemValueBool('check_for_working_wellknown_setup', true)) {
+			return SetupResult::info($this->l10n->t('`check_for_working_wellknown_setup` is set to false in your configuration, so this check was skipped.'));
+		}
+
+		$urls = [
+			['get', '/.well-known/webfinger', [200, 404], true],
+			['get', '/.well-known/nodeinfo', [200, 404], true],
+			['propfind', '/.well-known/caldav', [207], false],
+			['propfind', '/.well-known/carddav', [207], false],
+		];
+
+		foreach ($urls as [$verb,$url,$validStatuses,$checkCustomHeader]) {
+			$works = null;
+			foreach ($this->runRequest($url, $verb, ['httpErrors' => false, 'options' => ['allow_redirects' => ['track_redirects' => true]]]) as $response) {
+				// Check that the response status matches
+				$works = in_array($response->getStatusCode(), $validStatuses);
+				// and (if needed) the custom Nextcloud header is set
+				if ($checkCustomHeader) {
+					$works = $works && !empty($response->getHeader('X-NEXTCLOUD-WELL-KNOWN'));
+				} else {
+					// For default DAV endpoints we lack authorization, but we still can check that the redirect works as expected
+					if (!$works && $response->getStatusCode() === 401) {
+						$redirectHops = explode(',', $response->getHeader('X-Guzzle-Redirect-History'));
+						$effectiveUri = end($redirectHops);
+						$works = str_ends_with($effectiveUri, '/remote.php/dav/');
+					}
+				}
+				// Skip the other requests if one works
+				if ($works === true) {
+					break;
+				}
+			}
+			// If 'works' is null then we could not connect to the server
+			if ($works === null) {
+				return SetupResult::info(
+					$this->l10n->t('Could not check that your web server serves `.well-known` correctly. Please check manually.') . "\n" . $this->serverConfigHelp(),
+					$this->urlGenerator->linkToDocs('admin-setup-well-known-URL'),
+				);
+			}
+			// Otherwise if we fail we can abort here
+			if ($works === false) {
+				return SetupResult::warning(
+					$this->l10n->t("Your web server is not properly set up to resolve `.well-known` URLs, failed on:\n`%s`", [$url]),
+					$this->urlGenerator->linkToDocs('admin-setup-well-known-URL'),
+				);
+			}
+		}
+		return SetupResult::success(
+			$this->l10n->t('Your server is correctly configured to serve `.well-known` URLs.')
+		);
+	}
+}