Trigger STALE events when patching stale field

- Also moved the patch function into service, instead of performing the
  operation in the controller

src/lib/routes/admin-api/project/features.ts

@@ -172,15 +172,11 @@ export default class ProjectFeaturesController extends Controller {
         res: Response,
     ): Promise<void> {
         const { projectId, featureName } = req.params;
-        const featureToggle = await this.featureService.getFeatureMetadata(
-            featureName,
-        );
-        const { newDocument } = applyPatch(featureToggle, req.body);
-        const userName = extractUsername(req);
-        const updated = await this.featureService.updateFeatureToggle(
+        const updated = await this.featureService.patchFeature(
             projectId,
-            newDocument,
-            userName,
+            featureName,
+            extractUsername(req),
+            req.body,
         );
         res.status(200).json(updated);
     }

src/lib/services/feature-toggle-service-v2.ts

@@ -45,6 +45,7 @@ import {
 import { IFeatureEnvironmentStore } from '../types/stores/feature-environment-store';
 import { IFeatureToggleClientStore } from '../types/stores/feature-toggle-client-store';
 import { DEFAULT_ENV } from '../util/constants';
+import { applyPatch, deepClone, Operation } from 'fast-json-patch';
 
 class FeatureToggleServiceV2 {
     private logger: Logger;
@@ -94,6 +95,34 @@ class FeatureToggleServiceV2 {
         this.featureEnvironmentStore = featureEnvironmentStore;
     }
 
+    async patchFeature(
+        projectId: string,
+        featureName: string,
+        userName: string,
+        operations: Operation[],
+    ): Promise<FeatureToggle> {
+        const featureToggle = await this.getFeatureMetadata(featureName);
+
+        const { newDocument } = applyPatch(
+            deepClone(featureToggle),
+            operations,
+        );
+        const updated = await this.updateFeatureToggle(
+            projectId,
+            newDocument,
+            userName,
+        );
+        if (featureToggle.stale !== newDocument.stale) {
+            await this.eventStore.store({
+                type: newDocument.stale ? FEATURE_STALE_ON : FEATURE_STALE_OFF,
+                data: updated,
+                project: projectId,
+                createdBy: userName,
+            });
+        }
+        return updated;
+    }
+
     async createStrategy(
         strategyConfig: Omit<IStrategyConfig, 'id'>,
         projectId: string,

src/test/e2e/api/admin/project/features.e2e.test.ts

@@ -6,6 +6,8 @@ import {
     FEATURE_ENVIRONMENT_DISABLED,
     FEATURE_ENVIRONMENT_ENABLED,
     FEATURE_METADATA_UPDATED,
+    FEATURE_STALE_OFF,
+    FEATURE_STALE_ON,
     FEATURE_STRATEGY_REMOVE,
 } from '../../../../../lib/types/events';
 
@@ -531,6 +533,56 @@ test('Should patch feature toggle', async () => {
     expect(updateForOurToggle.data.type).toBe('kill-switch');
 });
 
+test('Patching feature toggles to stale should trigger FEATURE_STALE_ON event', async () => {
+    const url = '/api/admin/projects/default/features';
+    const name = 'toggle.stale.on.patch';
+    await app.request
+        .post(url)
+        .send({ name, description: 'some', type: 'release', stale: false })
+        .expect(201);
+    await app.request
+        .patch(`${url}/${name}`)
+        .send([{ op: 'replace', path: '/stale', value: true }])
+        .expect(200);
+
+    const { body: toggle } = await app.request.get(`${url}/${name}`);
+
+    expect(toggle.name).toBe(name);
+    expect(toggle.archived).toBeFalsy();
+    expect(toggle.stale).toBeTruthy();
+    const events = await db.stores.eventStore.getAll({
+        type: FEATURE_STALE_ON,
+    });
+    const updateForOurToggle = events.find((e) => e.data.name === name);
+    expect(updateForOurToggle).toBeTruthy();
+    expect(updateForOurToggle.data.stale).toBe(true);
+});
+
+test('Patching feature toggles to active (turning stale to false) should trigger FEATURE_STALE_OFF event', async () => {
+    const url = '/api/admin/projects/default/features';
+    const name = 'toggle.stale.off.patch';
+    await app.request
+        .post(url)
+        .send({ name, description: 'some', type: 'release', stale: true })
+        .expect(201);
+    await app.request
+        .patch(`${url}/${name}`)
+        .send([{ op: 'replace', path: '/stale', value: false }])
+        .expect(200);
+
+    const { body: toggle } = await app.request.get(`${url}/${name}`);
+
+    expect(toggle.name).toBe(name);
+    expect(toggle.archived).toBeFalsy();
+    expect(toggle.stale).toBe(false);
+    const events = await db.stores.eventStore.getAll({
+        type: FEATURE_STALE_OFF,
+    });
+    const updateForOurToggle = events.find((e) => e.data.name === name);
+    expect(updateForOurToggle).toBeTruthy();
+    expect(updateForOurToggle.data.stale).toBe(false);
+});
+
 test('Should archive feature toggle', async () => {
     const url = '/api/admin/projects/default/features';
     const name = 'new.toggle.archive';