feat(scheduler): notify on scheduled scan completion (#646)

Scheduled scan tasks now dispatch a completion alert through the
existing notification system: info when every image scanned cleanly,
warning when one or more images failed. The alert includes the task
name and the run's scanned/cached/failed summary so operators do not
need to open the task history.

backend/src/__tests__/scheduler-service.test.ts

@@ -18,6 +18,8 @@ const {
   mockCheckImage,
   mockDispatchAlert,
   mockGetProxyTarget,
+  mockIsTrivyAvailable,
+  mockScanAllNodeImages,
 } = vi.hoisted(() => ({
   mockGetDueScheduledTasks: vi.fn().mockReturnValue([]),
   mockCreateScheduledTaskRun: vi.fn().mockReturnValue(1),
@@ -44,6 +46,8 @@ const {
   mockCheckImage: vi.fn().mockResolvedValue({ hasUpdate: false }),
   mockDispatchAlert: vi.fn().mockResolvedValue(undefined),
   mockGetProxyTarget: vi.fn().mockReturnValue(null),
+  mockIsTrivyAvailable: vi.fn().mockReturnValue(true),
+  mockScanAllNodeImages: vi.fn().mockResolvedValue({ scanned: 0, skipped: 0, failed: 0 }),
 }));
 
 vi.mock('../services/DatabaseService', () => ({
@@ -129,6 +133,17 @@ vi.mock('../services/NodeRegistry', () => ({
   },
 }));
 
+vi.mock('../services/TrivyService', () => ({
+  default: {
+    getInstance: () => ({
+      isTrivyAvailable: mockIsTrivyAvailable,
+      scanAllNodeImages: mockScanAllNodeImages,
+      getSource: () => 'managed',
+      detectTrivy: vi.fn().mockResolvedValue(undefined),
+    }),
+  },
+}));
+
 import { SchedulerService } from '../services/SchedulerService';
 
 beforeEach(() => {
@@ -744,6 +759,111 @@ describe('SchedulerService - error handling', () => {
   });
 });
 
+// ── Scheduled scan completion notifications ───────────────────────────
+
+describe('SchedulerService - scheduled scan notifications', () => {
+  function makeScanTask(overrides: Partial<any> = {}) {
+    return {
+      id: 200,
+      name: 'nightly-scan',
+      action: 'scan',
+      cron_expression: '0 2 * * *',
+      enabled: true,
+      target_id: null,
+      node_id: 1,
+      created_by: 'admin',
+      last_status: null,
+      ...overrides,
+    };
+  }
+
+  it('dispatches info-level notification when scan completes cleanly', async () => {
+    mockGetScheduledTask.mockReturnValue(makeScanTask());
+    mockScanAllNodeImages.mockResolvedValue({ scanned: 3, skipped: 1, failed: 0 });
+
+    const svc = SchedulerService.getInstance();
+    await svc.triggerTask(200);
+
+    expect(mockDispatchAlert).toHaveBeenCalledWith(
+      'info',
+      expect.stringContaining('nightly-scan'),
+      undefined,
+    );
+    expect(mockDispatchAlert).toHaveBeenCalledWith(
+      'info',
+      expect.stringContaining('Scanned 3 image(s)'),
+      undefined,
+    );
+  });
+
+  it('dispatches warning-level notification when scan has failures', async () => {
+    mockGetScheduledTask.mockReturnValue(makeScanTask({ id: 201, name: 'flaky-scan' }));
+    mockScanAllNodeImages.mockResolvedValue({ scanned: 5, skipped: 0, failed: 2 });
+
+    const svc = SchedulerService.getInstance();
+    await svc.triggerTask(201);
+
+    expect(mockDispatchAlert).toHaveBeenCalledWith(
+      'warning',
+      expect.stringContaining('2 failed'),
+      undefined,
+    );
+  });
+
+  it('passes target_id to dispatchAlert when set', async () => {
+    mockGetScheduledTask.mockReturnValue(makeScanTask({ id: 202, target_id: 'web-stack' }));
+    mockScanAllNodeImages.mockResolvedValue({ scanned: 1, skipped: 0, failed: 0 });
+
+    const svc = SchedulerService.getInstance();
+    await svc.triggerTask(202);
+
+    expect(mockDispatchAlert).toHaveBeenCalledWith(
+      'info',
+      expect.stringContaining('completed'),
+      'web-stack',
+    );
+  });
+
+  it('fires only the scan notification when previous run was failure (no duplicate recovery alert)', async () => {
+    mockGetScheduledTask.mockReturnValue(makeScanTask({
+      id: 204,
+      name: 'recovered-scan',
+      last_status: 'failure', // Previous run failed
+    }));
+    mockScanAllNodeImages.mockResolvedValue({ scanned: 2, skipped: 0, failed: 0 });
+
+    const svc = SchedulerService.getInstance();
+    await svc.triggerTask(204);
+
+    expect(mockDispatchAlert).toHaveBeenCalledTimes(1);
+    expect(mockDispatchAlert).toHaveBeenCalledWith(
+      'info',
+      expect.stringContaining('recovered-scan'),
+      undefined,
+    );
+  });
+
+  it('does not dispatch a scan notification for non-scan actions', async () => {
+    mockGetScheduledTask.mockReturnValue({
+      id: 203,
+      name: 'restart-task',
+      action: 'restart',
+      cron_expression: '*/5 * * * *',
+      enabled: true,
+      target_id: 'my-stack',
+      node_id: 1,
+      created_by: 'admin',
+      last_status: null, // No previous failure → no recovery notification
+    });
+    mockGetContainersByStack.mockResolvedValue([{ Id: 'c1', Service: 'web' }]);
+
+    const svc = SchedulerService.getInstance();
+    await svc.triggerTask(203);
+
+    expect(mockDispatchAlert).not.toHaveBeenCalled();
+  });
+});
+
 // ── Cleanup ────────────────────────────────────────────────────────────
 
 describe('SchedulerService - cleanup', () => {

backend/src/services/SchedulerService.ts

@@ -241,6 +241,7 @@ export class SchedulerService {
             if (isDebugEnabled()) console.log(`[SchedulerService:debug] Task ${task.id} pre-checks passed, executing ${task.action}`);
             const actionStart = Date.now();
             let output = '';
+            let scanFailedCount = 0;
             switch (task.action) {
                 case 'restart':
                     output = await this.executeRestart(task);
@@ -254,9 +255,12 @@ export class SchedulerService {
                 case 'update':
                     output = await this.executeUpdate(task);
                     break;
-                case 'scan':
-                    output = await this.executeScan(task);
+                case 'scan': {
+                    const result = await this.executeScan(task);
+                    output = result.output;
+                    scanFailedCount = result.failed;
                     break;
+                }
             }
 
             if (isDebugEnabled()) console.log(`[SchedulerService:debug] Task ${task.id} action completed in ${Date.now() - actionStart}ms`);
@@ -275,7 +279,13 @@ export class SchedulerService {
                 output,
             });
             console.log(`[SchedulerService] Task "${task.name}" (id=${task.id}) completed successfully`);
-            if (task.last_status === 'failure') {
+            if (task.action === 'scan') {
+                NotificationService.getInstance().dispatchAlert(
+                    scanFailedCount > 0 ? 'warning' : 'info',
+                    `Scheduled scan "${task.name}" completed: ${output}`,
+                    task.target_id ?? undefined
+                );
+            } else if (task.last_status === 'failure') {
                 NotificationService.getInstance().dispatchAlert(
                     'info',
                     `Scheduled task "${task.name}" (${task.action}) recovered successfully`,
@@ -597,7 +607,7 @@ export class SchedulerService {
         return `Stack "${stackName}": updated (${updatedImages.join(', ')}).`;
     }
 
-    private async executeScan(task: ScheduledTask): Promise<string> {
+    private async executeScan(task: ScheduledTask): Promise<{ output: string; failed: number }> {
         const trivy = TrivyService.getInstance();
         if (!trivy.isTrivyAvailable()) {
             throw new Error('Trivy binary is not available on this node');
@@ -613,6 +623,6 @@ export class SchedulerService {
         const parts: string[] = [`Scanned ${summary.scanned} image(s)`];
         if (summary.skipped > 0) parts.push(`${summary.skipped} skipped (cached)`);
         if (summary.failed > 0) parts.push(`${summary.failed} failed`);
-        return parts.join('; ');
+        return { output: parts.join('; '), failed: summary.failed };
     }
 }