[Security Solution] Fix bug with redirect and add test (elastic#210188)

## Summary

It fixes a bug caused by the `latestStats$` being initialized with `[]`
empty array. The hook considers the state is _loading_ while the hook is
`null`.

https://github.com/elastic/kibana/blob/dde1bec88bc7a797c21d65305c23ab6c1dc6bed6/x-pack/solutions/security/plugins/security_solution/public/siem_migrations/rules/service/hooks/use_latest_stats.ts#L23-L26

The fix consists of initializing the `latestStats$` observable to `null`
instead of `[]`.

---------

Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com>
(cherry picked from commit dc3b4c8)

x-pack/solutions/security/plugins/security_solution/public/siem_migrations/rules/service/rule_migrations_service.test.ts

@@ -0,0 +1,335 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+/**
+ * SiemRulesMigrationsService.test.ts
+ *
+ * This file tests the SiemRulesMigrationsService class.
+ * We use Jest for assertions and mocking. We also use Jest’s fake timers to simulate the polling loop.
+ */
+
+import type { CoreStart } from '@kbn/core/public';
+import type { TraceOptions } from '@kbn/elastic-assistant/impl/assistant/types';
+import { firstValueFrom } from 'rxjs';
+import {
+  createRuleMigration,
+  upsertMigrationResources,
+  startRuleMigration as startRuleMigrationAPI,
+  getRuleMigrationStats,
+  getRuleMigrationsStatsAll,
+  getMissingResources,
+  getIntegrations,
+} from '../api';
+import type { CreateRuleMigrationRequestBody } from '../../../../common/siem_migrations/model/api/rules/rule_migration.gen';
+import { createTelemetryServiceMock } from '../../../common/lib/telemetry/telemetry_service.mock';
+import {
+  SiemMigrationRetryFilter,
+  SiemMigrationTaskStatus,
+} from '../../../../common/siem_migrations/constants';
+import type { StartPluginsDependencies } from '../../../types';
+import { getMissingCapabilities } from './capabilities';
+import * as i18n from './translations';
+import {
+  REQUEST_POLLING_INTERVAL_SECONDS,
+  SiemRulesMigrationsService,
+} from './rule_migrations_service';
+
+// --- Mocks for external modules ---
+
+jest.mock('../api', () => ({
+  createRuleMigration: jest.fn(),
+  upsertMigrationResources: jest.fn(),
+  startRuleMigration: jest.fn(),
+  getRuleMigrationStats: jest.fn(),
+  getRuleMigrationsStatsAll: jest.fn(),
+  getMissingResources: jest.fn(),
+  getIntegrations: jest.fn(),
+}));
+
+jest.mock('./capabilities', () => ({
+  getMissingCapabilities: jest.fn(() => []),
+}));
+
+jest.mock('../../../common/experimental_features_service', () => ({
+  ExperimentalFeaturesService: {
+    get: jest.fn(() => ({ siemMigrationsDisabled: false })),
+  },
+}));
+
+jest.mock('../../../common/hooks/use_license', () => ({
+  licenseService: {
+    isEnterprise: jest.fn(() => true),
+  },
+}));
+
+jest.mock('./notifications/success_notification', () => ({
+  getSuccessToast: jest.fn().mockReturnValue({ title: 'Success' }),
+}));
+
+jest.mock('./notifications/no_connector_notification', () => ({
+  getNoConnectorToast: jest.fn().mockReturnValue({ title: 'No Connector' }),
+}));
+
+jest.mock('./notifications/missing_capabilities_notification', () => ({
+  getMissingCapabilitiesToast: jest.fn().mockReturnValue({ title: 'Missing Capabilities' }),
+}));
+
+// --- End of mocks ---
+
+describe('SiemRulesMigrationsService', () => {
+  let service: SiemRulesMigrationsService;
+  let mockCore: CoreStart;
+  let mockPlugins: StartPluginsDependencies;
+  let mockNotifications: CoreStart['notifications'];
+  const mockTelemetry = createTelemetryServiceMock();
+
+  beforeEach(async () => {
+    jest.clearAllMocks();
+
+    // Create a fake notifications object to spy on toast calls
+    mockNotifications = {
+      toasts: { add: jest.fn(), addError: jest.fn(), addSuccess: jest.fn() },
+    } as unknown as CoreStart['notifications'];
+
+    // Minimal core stub
+    mockCore = {
+      application: { capabilities: {} },
+      notifications: mockNotifications,
+    } as CoreStart;
+
+    // Minimal plugins stub with spaces.getActiveSpace returning a fake space
+    mockPlugins = {
+      spaces: {
+        getActiveSpace: jest.fn().mockResolvedValue({ id: 'test-space' }),
+      },
+    } as unknown as StartPluginsDependencies;
+
+    // Ensure getRuleMigrationsStatsAll returns an empty array by default (so polling exits quickly)
+    (getRuleMigrationsStatsAll as jest.Mock).mockResolvedValue([]);
+
+    // Instantiate the service – note that the constructor calls getActiveSpace and startPolling
+    service = new SiemRulesMigrationsService(mockCore, mockPlugins, mockTelemetry);
+    // Wait for any async operations in the constructor to complete
+    await Promise.resolve();
+  });
+
+  describe('latestStats$', () => {
+    it('should be initialized to null', async () => {
+      // Instantiate the service – note that the constructor calls getActiveSpace and startPolling
+      const testService = new SiemRulesMigrationsService(mockCore, mockPlugins, mockTelemetry);
+      expect(await firstValueFrom(testService.getLatestStats$())).toBeNull();
+      await Promise.resolve();
+    });
+  });
+
+  describe('createRuleMigration', () => {
+    it('should throw an error when body is empty', async () => {
+      await expect(service.createRuleMigration([])).rejects.toThrow(i18n.EMPTY_RULES_ERROR);
+    });
+
+    it('should create migration with a single batch', async () => {
+      const body = [{ id: 'rule1' }] as CreateRuleMigrationRequestBody;
+      (createRuleMigration as jest.Mock).mockResolvedValue({ migration_id: 'mig-1' });
+
+      const migrationId = await service.createRuleMigration(body);
+
+      expect(createRuleMigration).toHaveBeenCalledTimes(1);
+      expect(createRuleMigration).toHaveBeenCalledWith({ migrationId: undefined, body });
+      expect(migrationId).toBe('mig-1');
+    });
+
+    it('should create migration in batches if body length exceeds the batch size', async () => {
+      // Create an array of 51 items (the service batches in chunks of 50)
+      const body = new Array(51).fill({ rule: 'rule' });
+      (createRuleMigration as jest.Mock)
+        .mockResolvedValueOnce({ migration_id: 'mig-1' })
+        .mockResolvedValueOnce({ migration_id: 'mig-2' });
+
+      const migrationId = await service.createRuleMigration(body);
+
+      expect(createRuleMigration).toHaveBeenCalledTimes(2);
+      // First call: first 50 items, migrationId undefined
+      expect((createRuleMigration as jest.Mock).mock.calls[0][0]).toEqual({
+        migrationId: undefined,
+        body: body.slice(0, 50),
+      });
+      // Second call: remaining 1 item, migrationId passed from previous batch
+      expect((createRuleMigration as jest.Mock).mock.calls[1][0]).toEqual({
+        migrationId: 'mig-1',
+        body: body.slice(50, 51),
+      });
+      expect(migrationId).toBe('mig-2');
+    });
+  });
+
+  describe('upsertMigrationResources', () => {
+    it('should throw an error when body is empty', async () => {
+      await expect(service.upsertMigrationResources('mig-1', [])).rejects.toThrow(
+        i18n.EMPTY_RULES_ERROR
+      );
+    });
+
+    it('should upsert resources in batches', async () => {
+      const body = new Array(51).fill({ resource: 'res' });
+      (upsertMigrationResources as jest.Mock).mockResolvedValue({});
+      await service.upsertMigrationResources('mig-1', body);
+
+      expect(upsertMigrationResources).toHaveBeenCalledTimes(2);
+      expect((upsertMigrationResources as jest.Mock).mock.calls[0][0]).toEqual({
+        migrationId: 'mig-1',
+        body: body.slice(0, 50),
+      });
+      expect((upsertMigrationResources as jest.Mock).mock.calls[1][0]).toEqual({
+        migrationId: 'mig-1',
+        body: body.slice(50, 51),
+      });
+    });
+  });
+
+  describe('startRuleMigration', () => {
+    it('should notify and not start migration if missing capabilities exist', async () => {
+      (getMissingCapabilities as jest.Mock).mockReturnValue([{ capability: 'cap' }]);
+
+      const result = await service.startRuleMigration('mig-1');
+      expect(mockNotifications.toasts.add).toHaveBeenCalled();
+      expect(result).toEqual({ started: false });
+    });
+
+    it('should notify and not start migration if connectorId is missing', async () => {
+      (getMissingCapabilities as jest.Mock).mockReturnValue([]);
+      // Force connectorId to be missing
+      jest.spyOn(service.connectorIdStorage, 'get').mockReturnValue(undefined);
+
+      const result = await service.startRuleMigration('mig-1');
+      expect(mockNotifications.toasts.add).toHaveBeenCalled();
+      expect(result).toEqual({ started: false });
+    });
+
+    it('should start migration successfully when capabilities and connectorId are present', async () => {
+      (getMissingCapabilities as jest.Mock).mockReturnValue([]);
+      // Simulate a valid connector id and trace options
+      jest.spyOn(service.connectorIdStorage, 'get').mockReturnValue('connector-123');
+      jest.spyOn(service.traceOptionsStorage, 'get').mockReturnValue({
+        langSmithProject: 'proj',
+        langSmithApiKey: 'key',
+      } as TraceOptions);
+      (startRuleMigrationAPI as jest.Mock).mockResolvedValue({ started: true });
+
+      // Spy on startPolling to ensure it is called after starting the migration
+      const startPollingSpy = jest.spyOn(service, 'startPolling');
+      const result = await service.startRuleMigration(
+        'mig-1',
+        SiemMigrationRetryFilter.NOT_FULLY_TRANSLATED
+      );
+
+      expect(startRuleMigrationAPI).toHaveBeenCalledWith({
+        migrationId: 'mig-1',
+        connectorId: 'connector-123',
+        retry: SiemMigrationRetryFilter.NOT_FULLY_TRANSLATED,
+        langSmithOptions: { project_name: 'proj', api_key: 'key' },
+      });
+      expect(startPollingSpy).toHaveBeenCalled();
+      expect(result).toEqual({ started: true });
+    });
+  });
+
+  describe('getRuleMigrationStats', () => {
+    it('should return migration stats', async () => {
+      const stats = { id: 'mig-1', status: SiemMigrationTaskStatus.RUNNING };
+      (getRuleMigrationStats as jest.Mock).mockResolvedValue(stats);
+
+      const result = await service.getRuleMigrationStats('mig-1');
+      expect(getRuleMigrationStats).toHaveBeenCalledWith({ migrationId: 'mig-1' });
+      expect(result).toEqual(stats);
+    });
+  });
+
+  describe('getRuleMigrationsStats', () => {
+    it('should fetch and update latest stats', async () => {
+      const statsArray = [
+        { id: 'mig-1', status: SiemMigrationTaskStatus.RUNNING },
+        { id: 'mig-2', status: SiemMigrationTaskStatus.FINISHED },
+      ];
+      (getRuleMigrationsStatsAll as jest.Mock).mockResolvedValue(statsArray);
+
+      const result = await service.getRuleMigrationsStats();
+      expect(getRuleMigrationsStatsAll).toHaveBeenCalled();
+      expect(result).toHaveLength(2);
+      expect(result[0].number).toBe(1);
+      expect(result[1].number).toBe(2);
+
+      const latestStats = await firstValueFrom(service.getLatestStats$());
+      expect(latestStats).toEqual(result);
+    });
+  });
+
+  describe('getMissingResources', () => {
+    it('should return missing resources', async () => {
+      const resources = [{ resource: 'res1' }];
+      (getMissingResources as jest.Mock).mockResolvedValue(resources);
+
+      const result = await service.getMissingResources('mig-1');
+      expect(getMissingResources).toHaveBeenCalledWith({ migrationId: 'mig-1' });
+      expect(result).toEqual(resources);
+    });
+  });
+
+  describe('getIntegrations', () => {
+    it('should return integrations', async () => {
+      const integrations = { integration1: { id: 'int-1' } };
+      (getIntegrations as jest.Mock).mockResolvedValue(integrations);
+
+      const result = await service.getIntegrations();
+      expect(getIntegrations).toHaveBeenCalledWith({});
+      expect(result).toEqual(integrations);
+    });
+  });
+
+  describe('Polling behavior', () => {
+    it('should poll and send a success toast when a migration finishes', async () => {
+      // Use fake timers to simulate delays inside the polling loop.
+      jest.useFakeTimers();
+
+      // Simulate a migration that is first reported as RUNNING and then FINISHED.
+      const runningMigration = { id: 'mig-1', status: SiemMigrationTaskStatus.RUNNING };
+      const finishedMigration = { id: 'mig-1', status: SiemMigrationTaskStatus.FINISHED };
+
+      // Override getRuleMigrationsStats to return our sequence:
+      // First call: running, then finished, then empty array.
+      const getStatsMock = jest
+        .fn()
+        .mockResolvedValue([finishedMigration])
+        .mockResolvedValueOnce([runningMigration]);
+
+      service.getRuleMigrationsStats = getStatsMock;
+
+      // Ensure a valid connector is present (so that a STOPPED migration would be resumed, if needed)
+      jest.spyOn(service.connectorIdStorage, 'get').mockReturnValue('connector-123');
+
+      // Start polling
+      service.startPolling();
+
+      // Resolve the first getRuleMigrationsStats promise
+      await Promise.resolve();
+
+      // Fast-forward the timer by the polling interval
+      jest.advanceTimersByTime(REQUEST_POLLING_INTERVAL_SECONDS * 1000);
+      // Resolve the timeout promise
+      await Promise.resolve();
+      // Resolve the second getRuleMigrationsStats promise
+      await Promise.resolve();
+
+      expect(getStatsMock).toHaveBeenCalledTimes(2);
+
+      // Expect that a success toast was added when the migration finished.
+      expect(mockNotifications.toasts.addSuccess).toHaveBeenCalled();
+
+      // Restore real timers.
+      jest.useRealTimers();
+    });
+  });
+});

x-pack/solutions/security/plugins/security_solution/public/siem_migrations/rules/service/rule_migrations_service.ts

@@ -57,11 +57,11 @@ import { getMissingCapabilitiesToast } from './notifications/missing_capabilitie
 const NAMESPACE_TRACE_OPTIONS_SESSION_STORAGE_KEY =
   `${DEFAULT_ASSISTANT_NAMESPACE}.${TRACE_OPTIONS_SESSION_STORAGE_KEY}` as const;
 
-const REQUEST_POLLING_INTERVAL_SECONDS = 10 as const;
+export const REQUEST_POLLING_INTERVAL_SECONDS = 10 as const;
 const CREATE_MIGRATION_BODY_BATCH_SIZE = 50 as const;
 
 export class SiemRulesMigrationsService {
-  private readonly latestStats$: BehaviorSubject<RuleMigrationStats[]>;
+  private readonly latestStats$: BehaviorSubject<RuleMigrationStats[] | null>;
   private isPolling = false;
   public connectorIdStorage = new RuleMigrationsStorage<string>('connectorId');
   public traceOptionsStorage = new RuleMigrationsStorage<TraceOptions>('traceOptions', {
@@ -76,15 +76,15 @@ export class SiemRulesMigrationsService {
     telemetryService: TelemetryServiceStart
   ) {
     this.telemetry = new SiemRulesMigrationsTelemetry(telemetryService);
-    this.latestStats$ = new BehaviorSubject<RuleMigrationStats[]>([]);
+    this.latestStats$ = new BehaviorSubject<RuleMigrationStats[] | null>(null);
 
     this.plugins.spaces.getActiveSpace().then((space) => {
       this.connectorIdStorage.setSpaceId(space.id);
       this.startPolling();
     });
   }
 
-  public getLatestStats$(): Observable<RuleMigrationStats[]> {
+  public getLatestStats$(): Observable<RuleMigrationStats[] | null> {
     return this.latestStats$.asObservable();
   }