feat: count created feature links with impact metrics

src/lib/features/feature-links/feature-link-service.test.ts

@@ -6,13 +6,21 @@ import {
     NotFoundError,
     OperationDeniedError,
 } from '../../error/index.js';
+import { fakeImpactMetricsResolver } from '../../../test/fixtures/fake-impact-metrics.js';
 
 test('create, update and delete feature link', async () => {
+    const flagResolver = { impactMetrics: fakeImpactMetricsResolver() };
     const { featureLinkStore, featureLinkService } =
         createFakeFeatureLinkService({
             getLogger,
+            flagResolver,
         } as unknown as IUnleashConfig);
 
+    flagResolver.impactMetrics.defineCounter(
+        'feature_link_count',
+        'Count of feature links',
+    );
+
     const link = await featureLinkService.createLink(
         'default',
         {
@@ -29,6 +37,10 @@ test('create, update and delete feature link', async () => {
         domain: 'example',
     });
 
+    expect(
+        flagResolver.impactMetrics.counters.get('feature_link_count')!.value,
+    ).toBe(1);
+
     const newLink = await featureLinkService.updateLink(
         { projectId: 'default', linkId: link.id },
         {
@@ -53,8 +65,10 @@ test('create, update and delete feature link', async () => {
 });
 
 test('cannot delete/update non existent link', async () => {
+    const flagResolver = { impactMetrics: fakeImpactMetricsResolver() };
     const { featureLinkService } = createFakeFeatureLinkService({
         getLogger,
+        flagResolver,
     } as unknown as IUnleashConfig);
 
     await expect(
@@ -77,8 +91,10 @@ test('cannot delete/update non existent link', async () => {
 });
 
 test('cannot create/update invalid link', async () => {
+    const flagResolver = { impactMetrics: fakeImpactMetricsResolver() };
     const { featureLinkService } = createFakeFeatureLinkService({
         getLogger,
+        flagResolver,
     } as unknown as IUnleashConfig);
 
     await expect(
@@ -107,8 +123,10 @@ test('cannot create/update invalid link', async () => {
 });
 
 test('cannot exceed allowed link count', async () => {
+    const flagResolver = { impactMetrics: fakeImpactMetricsResolver() };
     const { featureLinkService } = createFakeFeatureLinkService({
         getLogger,
+        flagResolver,
     } as unknown as IUnleashConfig);
 
     for (let i = 0; i < 10; i++) {

src/lib/features/feature-links/feature-link-service.ts

@@ -4,6 +4,7 @@ import {
     FeatureLinkRemovedEvent,
     FeatureLinkUpdatedEvent,
     type IAuditUser,
+    type IFlagResolver,
     type IUnleashConfig,
 } from '../../types/index.js';
 import type {
@@ -18,6 +19,7 @@ import {
 } from '../../error/index.js';
 import normalizeUrl from 'normalize-url';
 import { parse } from 'tldts';
+import { FEAUTRE_LINK_COUNT } from '../metrics/impact/define-impact-metrics.js';
 
 interface IFeatureLinkStoreObj {
     featureLinkStore: IFeatureLinkStore;
@@ -27,15 +29,20 @@ export default class FeatureLinkService {
     private logger: Logger;
     private featureLinkStore: IFeatureLinkStore;
     private eventService: EventService;
+    private flagResolver: IFlagResolver;
 
     constructor(
         stores: IFeatureLinkStoreObj,
-        { getLogger }: Pick<IUnleashConfig, 'getLogger'>,
+        {
+            getLogger,
+            flagResolver,
+        }: Pick<IUnleashConfig, 'getLogger' | 'flagResolver'>,
         eventService: EventService,
     ) {
         this.logger = getLogger('feature-links/feature-link-service.ts');
         this.featureLinkStore = stores.featureLinkStore;
         this.eventService = eventService;
+        this.flagResolver = flagResolver;
     }
 
     async getAll(): Promise<IFeatureLink[]> {
@@ -72,6 +79,8 @@ export default class FeatureLinkService {
             domain: domainWithoutSuffix,
         });
 
+        this.flagResolver.impactMetrics?.incrementCounter(FEAUTRE_LINK_COUNT);
+
         await this.eventService.storeEvent(
             new FeatureLinkAddedEvent({
                 featureName: newLink.featureName,

src/lib/features/feature-links/feature-link.e2e.test.ts

@@ -19,17 +19,7 @@ let featureLinkReadModel: IFeatureLinksReadModel;
 
 beforeAll(async () => {
     db = await dbInit('feature_link', getLogger);
-    app = await setupAppWithAuth(
+    app = await setupAppWithAuth(db.stores, {}, db.rawDatabase);
-        db.stores,
-        {
-            experimental: {
-                flags: {
-                    featureLinks: true,
-                },
-            },
-        },
-        db.rawDatabase,
-    );
     eventStore = db.stores.eventStore;
     featureLinkStore = db.stores.featureLinkStore;
     featureLinkReadModel = new FeatureLinksReadModel(

src/lib/features/metrics/impact/define-impact-metrics.ts

@@ -0,0 +1,10 @@
+import type { IFlagResolver } from '../../../types/index.js';
+
+export const FEAUTRE_LINK_COUNT = 'feature_link_count';
+
+export const defineImpactMetrics = (flagResolver: IFlagResolver) => {
+    flagResolver.impactMetrics?.defineCounter(
+        FEAUTRE_LINK_COUNT,
+        'Count of feature links',
+    );
+};

src/lib/server-impl.ts

@@ -183,6 +183,7 @@ import { testDbPrefix } from '../test/e2e/helpers/database-init.js';
 import type { RequestHandler } from 'express';
 import { UPDATE_REVISION } from './features/feature-toggle/configuration-revision-service.js';
 import type { IFeatureUsageInfo } from './services/version-service.js';
+import { defineImpactMetrics } from './features/metrics/impact/define-impact-metrics.js';
 
 export async function initialServiceSetup(
     { authentication }: Pick<IUnleashConfig, 'authentication'>,
@@ -232,6 +233,7 @@ export async function createApp(
         scheduleServices(services, config);
     }
 
+    defineImpactMetrics(config.flagResolver);
     const metricsMonitor = fm.createMetricsMonitor();
     const unleashSession = fm.createSessionDb(config, db);
 

src/test/fixtures/fake-impact-metrics.ts

@@ -0,0 +1,34 @@
+export const fakeImpactMetricsResolver = () => ({
+    counters: new Map<string, { value: number; help: string }>(),
+    gauges: new Map<string, { value: number; help: string }>(),
+
+    defineCounter(name: string, help: string) {
+        this.counters.set(name, { value: 0, help });
+    },
+
+    defineGauge(name: string, help: string) {
+        this.gauges.set(name, { value: 0, help });
+    },
+
+    incrementCounter(name: string, value: number = 1) {
+        const counter = this.counters.get(name);
+
+        if (!counter) {
+            return;
+        }
+
+        counter.value += value;
+        this.counters.set(name, counter);
+    },
+
+    updateGauge(name: string, value: number) {
+        const gauge = this.gauges.get(name);
+
+        if (!gauge) {
+            return;
+        }
+
+        gauge.value = value;
+        this.gauges.set(name, gauge);
+    },
+});