feat: add pre-flight check for HaRP K8s support

Signed-off-by: Oleksander Piskun <oleksandr2088@icloud.com>

Author: oleksandr-nc

lib/DeployActions/KubernetesActions.php

@@ -77,6 +77,11 @@ public function deployExApp(ExApp $exApp, DaemonConfig $daemonConfig, array $par
 		$harpUrl = $this->buildHarpK8sUrl($daemonConfig);
 		$this->initGuzzleClient($daemonConfig);
 
+		$pingError = $this->ping($daemonConfig);
+		if ($pingError !== '') {
+			return $pingError;
+		}
+
 		$roles = $params['k8s_service_roles'] ?? [];
 
 		if (empty($roles)) {
@@ -703,6 +708,42 @@ public function resolveExAppUrl(
 		return sprintf('%s/exapps/%s', $url, $appId);
 	}
 
+	/**
+	 * Pre-flight check: verify HaRP has a working Kubernetes backend.
+	 *
+	 * Calls GET /info and inspects the kubernetes status fields.
+	 * Returns empty string on success, actionable error message on failure.
+	 */
+	public function ping(DaemonConfig $daemonConfig): string {
+		$url = rtrim($daemonConfig->getProtocol() . '://' . $daemonConfig->getHost(), '/')
+			. '/exapps/app_api/info';
+		try {
+			$response = $this->guzzleClient->get($url, ['timeout' => 5]);
+			$data = json_decode((string)$response->getBody(), true);
+
+			$k8s = $data['kubernetes'] ?? null;
+			if ($k8s === null) {
+				return 'HaRP version is too old and does not report Kubernetes support. Please update HaRP.';
+			}
+			if (!($k8s['enabled'] ?? false)) {
+				return 'Kubernetes backend is disabled in HaRP. Set HP_K8S_ENABLED=true in HaRP configuration.';
+			}
+			if (!($k8s['reachable'] ?? false)) {
+				return sprintf(
+					'HaRP cannot reach the Kubernetes API server (%s). Check HP_K8S_API_SERVER, token, and network connectivity.',
+					$k8s['api_server'] ?? 'unknown'
+				);
+			}
+			return '';
+		} catch (GuzzleException $e) {
+			$this->logger->error(sprintf('K8s pre-flight check failed: %s', $e->getMessage()), ['exception' => $e]);
+			return sprintf('Cannot reach HaRP: %s', $e->getMessage());
+		} catch (Exception $e) {
+			$this->logger->error(sprintf('K8s pre-flight check failed: %s', $e->getMessage()), ['exception' => $e]);
+			return sprintf('K8s pre-flight check failed: %s', $e->getMessage());
+		}
+	}
+
 	public function buildHarpK8sUrl(DaemonConfig $daemonConfig): string {
 		$url = $daemonConfig->getProtocol() . '://' . $daemonConfig->getHost();
 		return rtrim($url, '/') . '/exapps/app_api/k8s';

lib/SetupChecks/DaemonCheck.php

@@ -12,6 +12,7 @@
 use OCA\AppAPI\AppInfo\Application;
 use OCA\AppAPI\Db\DaemonConfig;
 use OCA\AppAPI\DeployActions\DockerActions;
+use OCA\AppAPI\DeployActions\KubernetesActions;
 use OCA\AppAPI\Service\DaemonConfigService;
 use OCP\IAppConfig;
 use OCP\IConfig;
@@ -26,6 +27,7 @@ public function __construct(
 		private IConfig $config,
 		private IAppConfig $appConfig,
 		private DockerActions $dockerActions,
+		private KubernetesActions $kubernetesActions,
 		private LoggerInterface $logger,
 		private DaemonConfigService $daemonConfigService,
 	) {
@@ -59,13 +61,25 @@ public function run(): SetupResult {
 			);
 		}
 
+		$docsUrl = "https://docs.nextcloud.com/server/$serverVer/admin_manual/exapps_management/AppAPIAndExternalApps.html#setup-deploy-daemon";
+
+		if ($daemonConfig->getAcceptsDeployId() === KubernetesActions::DEPLOY_ID) {
+			$this->kubernetesActions->initGuzzleClient($daemonConfig);
+			$pingError = $this->kubernetesActions->ping($daemonConfig);
+			if ($pingError !== '') {
+				$this->logger->error(sprintf('K8s deploy daemon "%s" pre-flight check failed: %s', $daemonConfig->getName(), $pingError));
+				return SetupResult::error($pingError, $docsUrl);
+			}
+			return SetupResult::success();
+		}
+
 		$this->dockerActions->initGuzzleClient($daemonConfig);
 		$daemonConfigAccessible = $this->dockerActions->ping($this->dockerActions->buildDockerUrl($daemonConfig));
 		if (!$daemonConfigAccessible) {
 			$this->logger->error(sprintf('Deploy daemon "%s" is not accessible by Nextcloud. Please check its configuration', $daemonConfig->getName()));
 			return SetupResult::error(
 				$this->l10n->t('AppAPI default deploy daemon "%s" is not accessible. Please check the daemon configuration.', ['daemon' => $daemonConfig->getName()]),
-				"https://docs.nextcloud.com/server/$serverVer/admin_manual/exapps_management/AppAPIAndExternalApps.html#setup-deploy-daemon",
+				$docsUrl,
 			);
 		}