Added session management with periodic keepalive:

- **Backend**: Introduced `SessionController` with `/keepalive` endpoint to keep sessions active.
- **Frontend**: Enhanced session handling with `startSessionRefresh` and activity tracking in `backend.js`. Integrated session refresh initiation in `main.js`. Adjusted logic in `CalculationAssistant.vue` for input validation.
- **Other Changes**: Updated `BulkOperationRepository` cleanup interval to 60 minutes for improved timeout handling.

src/frontend/src/backend.js

@@ -10,6 +10,55 @@ const getCsrfToken = () => {
     return null;
 }
 
+let sessionRefreshInterval = null;
+let lastActivity = Date.now();
+
+
+const refreshSession = async () => {
+    try {
+        // Ein simpler authenticated GET request hält die Session am Leben
+        await fetch('/api/session/keepalive', {
+            method: 'GET',
+            credentials: 'include'
+        });
+        console.log('Session refreshed');
+    } catch (e) {
+        console.error('Session refresh failed', e);
+    }
+}
+
+
+const trackActivity = () => {
+    lastActivity = Date.now();
+}
+
+
+export const startSessionRefresh = () => {
+
+    ['mousedown', 'keypress', 'scroll', 'touchstart'].forEach(event => {
+        document.addEventListener(event, trackActivity);
+    });
+
+
+    if (sessionRefreshInterval) {
+        clearInterval(sessionRefreshInterval);
+    }
+
+    sessionRefreshInterval = setInterval(() => {
+        const timeSinceActivity = Date.now() - lastActivity;
+
+        if (timeSinceActivity < (12 * 60 * 60 * 1000)) {
+            refreshSession();
+        }
+    }, 10 * 60 * 1000);
+}
+
+export const stopSessionRefresh = () => {
+    if (sessionRefreshInterval) {
+        clearInterval(sessionRefreshInterval);
+    }
+}
+
 const performRequest = async (requestingStore, method, url, body, expectResponse = true, expectedException = null) => {
 
     const params = {
@@ -124,6 +173,12 @@ const executeRequest = async (requestingStore, request) => {
         throw e;
     });
 
+    if (response.status === 401) {
+        logger.warn('Session expired, redirecting to login...');
+        window.location.href = '/oauth2/authorization/azure';
+        return Promise.reject(new Error('Session expired'));
+    }
+
     let data = null;
     if (request.expectResponse) {
         try {
@@ -173,4 +228,4 @@ const executeRequest = async (requestingStore, request) => {
 }
 
 export default performRequest;
-export {performUpload, performDownload, getCsrfToken};
+export {performUpload, performDownload, getCsrfToken, startSessionRefresh, stopSessionRefresh};

src/frontend/src/main.js

@@ -3,6 +3,7 @@ import router from './router.js';
 import { setupErrorBuffer } from './store/error.js'
 import {createApp} from 'vue'
 import {createPinia} from 'pinia';
+import {startSessionRefresh} from "@/backend.js";
 import App from './App.vue'
 
 import {
@@ -31,6 +32,9 @@ import {
     PhCloudX, PhDesktop, PhHardDrives
 } from "@phosphor-icons/vue";
 
+
+
+
 const app = createApp(App);
 const pinia = createPinia();
 app.use(pinia);
@@ -72,5 +76,6 @@ app.use(router);
 //app.component('base-button', () => import('./components/UI/BasicButton.vue'));
 //app.component('base-badge', () => import('./components/UI/BasicBadge.vue'));
 setupErrorBuffer()
+startSessionRefresh();
 
 app.mount('#app');

src/frontend/src/pages/CalculationAssistant.vue

@@ -150,7 +150,10 @@ export default {
     },
     parsePartNumbers() {
       this.closeModal('partNumber');
-      this.assistantStore.getMaterialsAndSuppliers(this.partNumberField);
+
+      if(this.partNumberField.trim().length !== 0)
+        this.assistantStore.getMaterialsAndSuppliers(this.partNumberField);
+
       this.partNumberField = '';
     },
     addCreatedNode(supplier) {

src/main/java/de/avatic/lcc/controller/SessionController.java

@@ -0,0 +1,23 @@
+package de.avatic.lcc.controller;
+
+import org.springframework.security.core.Authentication;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.util.Map;
+
+@RestController
+@RequestMapping("/api/session")
+public class SessionController {
+
+    @GetMapping("/keepalive")
+    public Map<String, Object> keepalive(Authentication authentication) {
+
+        return Map.of(
+                "status", "ok",
+                "user", authentication.getName(),
+                "timestamp", System.currentTimeMillis()
+        );
+    }
+}

src/main/java/de/avatic/lcc/repositories/bulk/BulkOperationRepository.java

@@ -135,7 +135,7 @@ public class BulkOperationRepository {
     private void cleanupTimeouts(Integer userId) {
 
         String sql = """
-                UPDATE bulk_operation SET state = 'EXCEPTION' WHERE user_id = ? AND (state = 'PROCESSING' OR state = 'SCHEDULED') AND created_at < NOW() - INTERVAL 30 MINUTE
+                UPDATE bulk_operation SET state = 'EXCEPTION' WHERE user_id = ? AND (state = 'PROCESSING' OR state = 'SCHEDULED') AND created_at < NOW() - INTERVAL 60 MINUTE
                 """;
 
         jdbcTemplate.update(sql, userId);