Fix backend issues in desktop app (#4995)

# Description of Changes
Fixes two distinct but related issues in the backend of the desktop app:
- Correctly shows tools as unavaialable when the backend doesn't have
the dependencies or has disabled them etc. (same as web version - this
primarily didn't work on desktop because the app spawns before the
backend is running)
- Fixes infinite re-rendering issues caused by the app polling whether
the backend is healthy or not

app/core/src/main/java/stirling/software/SPDF/config/ExternalAppDepConfig.java

@@ -25,6 +25,7 @@ public class ExternalAppDepConfig {
     private final String weasyprintPath;
     private final String unoconvPath;
     private final Map<String, List<String>> commandToGroupMapping;
+    private volatile boolean dependenciesChecked = false;
 
     public ExternalAppDepConfig(
             EndpointConfiguration endpointConfiguration, RuntimePathConfig runtimePathConfig) {
@@ -111,6 +112,10 @@ public class ExternalAppDepConfig {
         }
     }
 
+    public boolean isDependenciesChecked() {
+        return dependenciesChecked;
+    }
+
     @PostConstruct
     public void checkDependencies() {
         // Check core dependencies
@@ -162,5 +167,7 @@ public class ExternalAppDepConfig {
             }
         }
         endpointConfiguration.logDisabledEndpointsSummary();
+        dependenciesChecked = true;
+        log.info("Dependency checks completed");
     }
 }

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/ConfigController.java

@@ -35,6 +35,7 @@ public class ConfigController {
     private final EndpointConfiguration endpointConfiguration;
     private final ServerCertificateServiceInterface serverCertificateService;
     private final UserServiceInterface userService;
+    private final stirling.software.SPDF.config.ExternalAppDepConfig externalAppDepConfig;
 
     public ConfigController(
             ApplicationProperties applicationProperties,
@@ -43,12 +44,14 @@ public class ConfigController {
             @org.springframework.beans.factory.annotation.Autowired(required = false)
                     ServerCertificateServiceInterface serverCertificateService,
             @org.springframework.beans.factory.annotation.Autowired(required = false)
-                    UserServiceInterface userService) {
+                    UserServiceInterface userService,
+            stirling.software.SPDF.config.ExternalAppDepConfig externalAppDepConfig) {
         this.applicationProperties = applicationProperties;
         this.applicationContext = applicationContext;
         this.endpointConfiguration = endpointConfiguration;
         this.serverCertificateService = serverCertificateService;
         this.userService = userService;
+        this.externalAppDepConfig = externalAppDepConfig;
     }
 
     @GetMapping("/app-config")
@@ -56,6 +59,9 @@ public class ConfigController {
         Map<String, Object> configData = new HashMap<>();
 
         try {
+            // Add dependency check status
+            configData.put("dependenciesReady", externalAppDepConfig.isDependenciesChecked());
+
             // Get AppConfig bean
             AppConfig appConfig = applicationContext.getBean(AppConfig.class);
 

frontend/src-tauri/src/commands/health.rs

@@ -1,16 +0,0 @@
-use reqwest;
-
-#[tauri::command]
-pub async fn check_backend_health(port: u16) -> Result<bool, String> {
-    let url = format!("http://localhost:{}/api/v1/info/status", port);
-
-    match reqwest::Client::new()
-        .get(&url)
-        .timeout(std::time::Duration::from_secs(5))
-        .send()
-        .await
-    {
-        Ok(response) => Ok(response.status().is_success()),
-        Err(_) => Ok(false), // Return false instead of error for connection failures
-    }
-}

frontend/src-tauri/src/commands/mod.rs

@@ -3,7 +3,6 @@ pub mod files;
 pub mod connection;
 pub mod auth;
 pub mod default_app;
-pub mod health;
 
 pub use backend::{cleanup_backend, get_backend_port, start_backend};
 pub use files::{add_opened_file, clear_opened_files, get_opened_files};
@@ -24,4 +23,3 @@ pub use auth::{
     start_oauth_login,
 };
 pub use default_app::{is_default_pdf_handler, set_as_default_pdf_handler};
-pub use health::check_backend_health;

frontend/src-tauri/src/lib.rs

@@ -6,7 +6,6 @@ mod state;
 
 use commands::{
     add_opened_file,
-    check_backend_health,
     cleanup_backend,
     clear_auth_token,
     clear_opened_files,
@@ -94,7 +93,6 @@ pub fn run() {
       set_as_default_pdf_handler,
       is_first_launch,
       reset_setup_completion,
-      check_backend_health,
       login,
       save_auth_token,
       get_auth_token,

frontend/src/core/contexts/AppConfigContext.tsx

@@ -42,6 +42,7 @@ export interface AppConfig {
   appVersion?: string;
   machineType?: string;
   activeSecurity?: boolean;
+  dependenciesReady?: boolean;
   error?: string;
 }
 

frontend/src/core/hooks/useBackendHealth.ts

@@ -4,8 +4,6 @@ export function useBackendHealth(): BackendHealthState {
   return {
     status: 'healthy',
     message: null,
-    isChecking: false,
-    lastChecked: Date.now(),
     error: null,
     isHealthy: true,
   };

frontend/src/core/types/backendHealth.ts

@@ -3,8 +3,6 @@ export type BackendStatus = 'stopped' | 'starting' | 'healthy' | 'unhealthy';
 export interface BackendHealthState {
   status: BackendStatus;
   message?: string | null;
-  lastChecked?: number;
-  isChecking: boolean;
   error: string | null;
   isHealthy: boolean;
 }

frontend/src/desktop/components/BackendHealthIndicator.tsx

@@ -13,10 +13,10 @@ export const BackendHealthIndicator: React.FC<BackendHealthIndicatorProps> = ({
   const { t } = useTranslation();
   const theme = useMantineTheme();
   const colorScheme = useComputedColorScheme('light');
-  const { isHealthy, isChecking, checkHealth } = useBackendHealth();
+  const { status, isHealthy, checkHealth } = useBackendHealth();
 
   const label = useMemo(() => {
-    if (isChecking) {
+    if (status === 'starting') {
       return t('backendHealth.checking', 'Checking backend status...');
     }
 
@@ -25,17 +25,17 @@ export const BackendHealthIndicator: React.FC<BackendHealthIndicatorProps> = ({
     }
 
     return t('backendHealth.offline', 'Backend Offline');
-  }, [isChecking, isHealthy, t]);
+  }, [status, isHealthy, t]);
 
   const dotColor = useMemo(() => {
-    if (isChecking) {
+    if (status === 'starting') {
       return theme.colors.yellow?.[5] ?? '#fcc419';
     }
     if (isHealthy) {
       return theme.colors.green?.[5] ?? '#37b24d';
     }
     return theme.colors.red?.[6] ?? '#e03131';
-  }, [isChecking, isHealthy, theme.colors.green, theme.colors.red, theme.colors.yellow]);
+  }, [status, isHealthy, theme.colors.green, theme.colors.red, theme.colors.yellow]);
 
   const handleKeyDown = useCallback((event: React.KeyboardEvent<HTMLSpanElement>) => {
     if (event.key === 'Enter' || event.key === ' ') {

frontend/src/desktop/hooks/useEndpointConfig.ts

@@ -6,6 +6,7 @@ import { tauriBackendService } from '@app/services/tauriBackendService';
 import { isBackendNotReadyError } from '@app/constants/backendErrors';
 import type { EndpointAvailabilityDetails } from '@app/types/endpointAvailability';
 import { connectionModeService } from '@desktop/services/connectionModeService';
+import type { AppConfig } from '@app/contexts/AppConfigContext';
 
 
 interface EndpointConfig {
@@ -28,6 +29,17 @@ function getErrorMessage(err: unknown): string {
   return 'Unknown error occurred';
 }
 
+async function checkDependenciesReady(): Promise<boolean> {
+  try {
+    const response = await apiClient.get<AppConfig>('/api/v1/config/app-config', {
+      suppressErrorToast: true,
+    });
+    return response.data?.dependenciesReady ?? false;
+  } catch {
+    return false;
+  }
+}
+
 /**
  * Desktop-specific endpoint checker that hits the backend directly via axios.
  */
@@ -38,7 +50,7 @@ export function useEndpointEnabled(endpoint: string): {
   refetch: () => Promise<void>;
 } {
   const { t } = useTranslation();
-  const [enabled, setEnabled] = useState<boolean | null>(() => (endpoint ? true : null));
+  const [enabled, setEnabled] = useState<boolean | null>(null);
   const [loading, setLoading] = useState(false);
   const [error, setError] = useState<string | null>(null);
   const isMountedRef = useRef(true);
@@ -68,6 +80,11 @@ export function useEndpointEnabled(endpoint: string): {
       return;
     }
 
+    const dependenciesReady = await checkDependenciesReady();
+    if (!dependenciesReady) {
+      return; // Health monitor will trigger retry when truly ready
+    }
+
     try {
       setError(null);
 
@@ -76,27 +93,27 @@ export function useEndpointEnabled(endpoint: string): {
         suppressErrorToast: true,
       });
 
-      if (!isMountedRef.current) return;
       setEnabled(response.data);
     } catch (err: unknown) {
       const isBackendStarting = isBackendNotReadyError(err);
       const message = getErrorMessage(err);
-      if (!isMountedRef.current) return;
-      setError(isBackendStarting ? t('backendHealth.starting', 'Backend starting up...') : message);
-      setEnabled(true);
 
-      if (!retryTimeoutRef.current) {
-        retryTimeoutRef.current = setTimeout(() => {
-          retryTimeoutRef.current = null;
-          fetchEndpointStatus();
-        }, RETRY_DELAY_MS);
+      if (isBackendStarting) {
+        setError(t('backendHealth.starting', 'Backend starting up...'));
+        if (!retryTimeoutRef.current) {
+          retryTimeoutRef.current = setTimeout(() => {
+            retryTimeoutRef.current = null;
+            fetchEndpointStatus();
+          }, RETRY_DELAY_MS);
+        }
+      } else {
+        setError(message);
+        setEnabled(false);
       }
     } finally {
-      if (isMountedRef.current) {
-        setLoading(false);
-      }
+      setLoading(false);
     }
-  }, [endpoint, clearRetryTimeout]);
+  }, [endpoint, clearRetryTimeout, t]);
 
   useEffect(() => {
     if (!endpoint) {
@@ -136,15 +153,9 @@ export function useMultipleEndpointsEnabled(endpoints: string[]): {
   refetch: () => Promise<void>;
 } {
   const { t } = useTranslation();
-  const [endpointStatus, setEndpointStatus] = useState<Record<string, boolean>>(() => {
-    if (!endpoints || endpoints.length === 0) return {};
-    return endpoints.reduce((acc, endpointName) => {
-      acc[endpointName] = true;
-      return acc;
-    }, {} as Record<string, boolean>);
-  });
+  const [endpointStatus, setEndpointStatus] = useState<Record<string, boolean>>({});
   const [endpointDetails, setEndpointDetails] = useState<Record<string, EndpointAvailabilityDetails>>({});
-  const [loading, setLoading] = useState(false);
+  const [loading, setLoading] = useState(true);
   const [error, setError] = useState<string | null>(null);
   const isMountedRef = useRef(true);
   const retryTimeoutRef = useRef<ReturnType<typeof setTimeout> | null>(null);
@@ -167,26 +178,31 @@ export function useMultipleEndpointsEnabled(endpoints: string[]): {
     clearRetryTimeout();
 
     if (!endpoints || endpoints.length === 0) {
-      if (!isMountedRef.current) return;
       setEndpointStatus({});
       setLoading(false);
       return;
     }
 
+    const dependenciesReady = await checkDependenciesReady();
+    if (!dependenciesReady) {
+      return; // Health monitor will trigger retry when truly ready
+    }
+
     try {
       setError(null);
 
       const endpointsParam = endpoints.join(',');
 
-      const response = await apiClient.get<Record<string, EndpointAvailabilityDetails>>('/api/v1/config/endpoints-availability', {
-        params: { endpoints: endpointsParam },
-        suppressErrorToast: true,
-      });
+      const response = await apiClient.get<Record<string, EndpointAvailabilityDetails>>(
+        `/api/v1/config/endpoints-availability?endpoints=${encodeURIComponent(endpointsParam)}`,
+        {
+          suppressErrorToast: true,
+        }
+      );
 
-      if (!isMountedRef.current) return;
       const details = Object.entries(response.data).reduce((acc, [endpointName, detail]) => {
         acc[endpointName] = {
-          enabled: detail?.enabled ?? true,
+          enabled: detail?.enabled ?? false,
           reason: detail?.reason ?? null,
         };
         return acc;
@@ -198,34 +214,34 @@ export function useMultipleEndpointsEnabled(endpoints: string[]): {
       }, {} as Record<string, boolean>);
 
       setEndpointDetails(prev => ({ ...prev, ...details }));
-      setEndpointStatus(statusMap);
+      setEndpointStatus(prev => ({ ...prev, ...statusMap }));
     } catch (err: unknown) {
       const isBackendStarting = isBackendNotReadyError(err);
       const message = getErrorMessage(err);
-      if (!isMountedRef.current) return;
-      setError(isBackendStarting ? t('backendHealth.starting', 'Backend starting up...') : message);
 
-      const fallbackStatus = endpoints.reduce((acc, endpointName) => {
-        const fallbackDetail: EndpointAvailabilityDetails = { enabled: true, reason: null };
-        acc.status[endpointName] = true;
-        acc.details[endpointName] = fallbackDetail;
-        return acc;
-      }, { status: {} as Record<string, boolean>, details: {} as Record<string, EndpointAvailabilityDetails> });
-      setEndpointStatus(fallbackStatus.status);
-      setEndpointDetails(prev => ({ ...prev, ...fallbackStatus.details }));
-
-      if (!retryTimeoutRef.current) {
-        retryTimeoutRef.current = setTimeout(() => {
-          retryTimeoutRef.current = null;
-          fetchAllEndpointStatuses();
-        }, RETRY_DELAY_MS);
+      if (isBackendStarting) {
+        setError(t('backendHealth.starting', 'Backend starting up...'));
+        if (!retryTimeoutRef.current) {
+          retryTimeoutRef.current = setTimeout(() => {
+            retryTimeoutRef.current = null;
+            fetchAllEndpointStatuses();
+          }, RETRY_DELAY_MS);
+        }
+      } else {
+        setError(message);
+        const fallbackStatus = endpoints.reduce((acc, endpointName) => {
+          const fallbackDetail: EndpointAvailabilityDetails = { enabled: false, reason: 'UNKNOWN' };
+          acc.status[endpointName] = false;
+          acc.details[endpointName] = fallbackDetail;
+          return acc;
+        }, { status: {} as Record<string, boolean>, details: {} as Record<string, EndpointAvailabilityDetails> });
+        setEndpointStatus(fallbackStatus.status);
+        setEndpointDetails(prev => ({ ...prev, ...fallbackStatus.details }));
       }
     } finally {
-      if (isMountedRef.current) {
-        setLoading(false);
-      }
+      setLoading(false);
     }
-  }, [endpoints, clearRetryTimeout]);
+  }, [endpoints, clearRetryTimeout, t]);
 
   useEffect(() => {
     if (!endpoints || endpoints.length === 0) {

frontend/src/desktop/services/backendHealthMonitor.ts

@@ -10,7 +10,6 @@ class BackendHealthMonitor {
   private readonly intervalMs: number;
   private state: BackendHealthState = {
     status: tauriBackendService.getBackendStatus(),
-    isChecking: false,
     error: null,
     isHealthy: tauriBackendService.getBackendStatus() === 'healthy',
   };
@@ -26,20 +25,30 @@ class BackendHealthMonitor {
         message: status === 'healthy'
           ? i18n.t('backendHealth.online', 'Backend Online')
           : this.state.message ?? i18n.t('backendHealth.offline', 'Backend Offline'),
-        isChecking: status === 'healthy' ? false : this.state.isChecking,
       });
     });
   }
 
   private updateState(partial: Partial<BackendHealthState>) {
     const nextStatus = partial.status ?? this.state.status;
-    this.state = {
+    const nextState = {
       ...this.state,
       ...partial,
       status: nextStatus,
       isHealthy: nextStatus === 'healthy',
     };
-    this.listeners.forEach((listener) => listener(this.state));
+
+    // Only notify listeners if meaningful state changed
+    const meaningfulChange =
+      this.state.status !== nextState.status ||
+      this.state.error !== nextState.error ||
+      this.state.message !== nextState.message;
+
+    this.state = nextState;
+
+    if (meaningfulChange) {
+      this.listeners.forEach((listener) => listener(this.state));
+    }
   }
 
   private ensurePolling() {
@@ -60,29 +69,19 @@ class BackendHealthMonitor {
   }
 
   private async pollOnce(): Promise<boolean> {
-    this.updateState({
-      isChecking: true,
-      lastChecked: Date.now(),
-      error: this.state.error ?? 'Backend offline',
-    });
-
     try {
       const healthy = await tauriBackendService.checkBackendHealth();
       if (healthy) {
         this.updateState({
           status: 'healthy',
-          isChecking: false,
           message: i18n.t('backendHealth.online', 'Backend Online'),
           error: null,
-          lastChecked: Date.now(),
         });
       } else {
         this.updateState({
           status: 'unhealthy',
-          isChecking: false,
           message: i18n.t('backendHealth.offline', 'Backend Offline'),
           error: i18n.t('backendHealth.offline', 'Backend Offline'),
-          lastChecked: Date.now(),
         });
       }
       return healthy;
@@ -90,10 +89,8 @@ class BackendHealthMonitor {
       console.error('[BackendHealthMonitor] Health check failed:', error);
       this.updateState({
         status: 'unhealthy',
-        isChecking: false,
         message: 'Backend is unavailable',
         error: 'Backend offline',
-        lastChecked: Date.now(),
       });
       return false;
     }

frontend/src/desktop/services/tauriBackendService.ts

@@ -133,7 +133,8 @@ export class TauriBackendService {
   async checkBackendHealth(): Promise<boolean> {
     const mode = await connectionModeService.getCurrentMode();
 
-    // For self-hosted mode, check the configured remote server
+    // Determine base URL based on mode
+    let baseUrl: string;
     if (mode === 'selfhosted') {
       const serverConfig = await connectionModeService.getServerConfig();
       if (!serverConfig) {
@@ -141,47 +142,37 @@ export class TauriBackendService {
         this.setStatus('unhealthy');
         return false;
       }
+      baseUrl = serverConfig.url.replace(/\/$/, '');
+    } else {
+      // SaaS mode - check bundled local backend
+      if (!this.backendStarted) {
+        this.setStatus('stopped');
+        return false;
+      }
+      if (!this.backendPort) {
+        return false;
+      }
+      baseUrl = `http://localhost:${this.backendPort}`;
+    }
 
-      try {
-        const baseUrl = serverConfig.url.replace(/\/$/, '');
-        const healthUrl = `${baseUrl}/api/v1/info/status`;
-        const response = await fetch(healthUrl, {
-          method: 'GET',
-          connectTimeout: 5000,
-        });
+    // Check if backend is ready (dependencies checked)
+    try {
+      const configUrl = `${baseUrl}/api/v1/config/app-config`;
+      const response = await fetch(configUrl, {
+        method: 'GET',
+        connectTimeout: 5000,
+      });
 
-        const isHealthy = response.ok;
-        this.setStatus(isHealthy ? 'healthy' : 'unhealthy');
-        return isHealthy;
-      } catch (error) {
-        const errorStr = String(error);
-        if (!errorStr.includes('connection refused') && !errorStr.includes('No connection could be made')) {
-          console.error('[TauriBackendService] Self-hosted server health check failed:', error);
-        }
+      if (!response.ok) {
         this.setStatus('unhealthy');
         return false;
       }
-    }
 
-    // For SaaS mode, check the bundled local backend via Rust
-    if (!this.backendStarted) {
-      this.setStatus('stopped');
-      return false;
-    }
-
-    if (!this.backendPort) {
-      return false;
-    }
-
-    try {
-      const isHealthy = await invoke<boolean>('check_backend_health', { port: this.backendPort });
-      this.setStatus(isHealthy ? 'healthy' : 'unhealthy');
-      return isHealthy;
-    } catch (error) {
-      const errorStr = String(error);
-      if (!errorStr.includes('connection refused') && !errorStr.includes('No connection could be made')) {
-        console.error('[TauriBackendService] Bundled backend health check failed:', error);
-      }
+      const data = await response.json();
+      const dependenciesReady = data.dependenciesReady === true;
+      this.setStatus(dependenciesReady ? 'healthy' : 'starting');
+      return dependenciesReady;
+    } catch {
       this.setStatus('unhealthy');
       return false;
     }