Add a precomputed requestor test

Author: sameerank

src/precomputed-requestor.spec.ts

@@ -0,0 +1,111 @@
+import ApiEndpoints from './api-endpoints';
+import { IConfigurationStore } from './configuration-store/configuration-store';
+import { MemoryOnlyConfigurationStore } from './configuration-store/memory.store';
+import FetchHttpClient, { IHttpClient } from './http-client';
+import { PrecomputedFlag } from './interfaces';
+import ConfigurationRequestor from './precomputed-requestor';
+
+const MOCK_PRECOMPUTED_RESPONSE = {
+  flags: {
+    'precomputed-flag-1': {
+      allocationKey: 'default',
+      variationKey: 'true-variation',
+      variationType: 'BOOLEAN',
+      variationValue: 'true',
+      extraLogging: {},
+      doLog: true,
+    },
+    'precomputed-flag-2': {
+      allocationKey: 'test-group',
+      variationKey: 'variation-a',
+      variationType: 'STRING',
+      variationValue: 'variation-a',
+      extraLogging: {},
+      doLog: true,
+    },
+  },
+  environment: 'production',
+  createdAt: '2024-03-20T00:00:00Z',
+};
+
+describe('PrecomputedRequestor', () => {
+  let precomputedFlagStore: IConfigurationStore<PrecomputedFlag>;
+  let httpClient: IHttpClient;
+  let configurationRequestor: ConfigurationRequestor;
+  let fetchSpy: jest.Mock;
+
+  beforeEach(() => {
+    const apiEndpoints = new ApiEndpoints({
+      baseUrl: 'http://127.0.0.1:4000',
+      queryParams: {
+        apiKey: 'dummy',
+        sdkName: 'js-client-sdk-common',
+        sdkVersion: '1.0.0',
+      },
+    });
+    httpClient = new FetchHttpClient(apiEndpoints, 1000);
+    precomputedFlagStore = new MemoryOnlyConfigurationStore<PrecomputedFlag>();
+    configurationRequestor = new ConfigurationRequestor(httpClient, precomputedFlagStore);
+
+    fetchSpy = jest.fn(() => {
+      return Promise.resolve({
+        ok: true,
+        status: 200,
+        json: () => Promise.resolve(MOCK_PRECOMPUTED_RESPONSE),
+      });
+    }) as jest.Mock;
+    global.fetch = fetchSpy;
+  });
+
+  afterEach(() => {
+    jest.clearAllMocks();
+  });
+
+  afterAll(() => {
+    jest.restoreAllMocks();
+  });
+
+  describe('Precomputed flags', () => {
+    it('Fetches and stores precomputed flag configuration', async () => {
+      await configurationRequestor.fetchAndStorePrecomputedFlags();
+
+      expect(fetchSpy).toHaveBeenCalledTimes(1);
+
+      expect(precomputedFlagStore.getKeys().length).toBe(2);
+
+      const flag1 = precomputedFlagStore.get('precomputed-flag-1');
+      expect(flag1?.allocationKey).toBe('default');
+      expect(flag1?.variationKey).toBe('true-variation');
+      expect(flag1?.variationType).toBe('BOOLEAN');
+      expect(flag1?.variationValue).toBe('true');
+      expect(flag1?.extraLogging).toEqual({});
+      expect(flag1?.doLog).toBe(true);
+
+      const flag2 = precomputedFlagStore.get('precomputed-flag-2');
+      expect(flag2?.allocationKey).toBe('test-group');
+      expect(flag2?.variationKey).toBe('variation-a');
+      expect(flag2?.variationType).toBe('STRING');
+      expect(flag2?.variationValue).toBe('variation-a');
+      expect(flag2?.extraLogging).toEqual({});
+      expect(flag2?.doLog).toBe(true);
+
+      expect(precomputedFlagStore.getEnvironment()).toBe('production');
+      expect(precomputedFlagStore.getConfigPublishedAt()).toBe('2024-03-20T00:00:00Z');
+    });
+
+    it('Handles empty response gracefully', async () => {
+      fetchSpy.mockImplementationOnce(() =>
+        Promise.resolve({
+          ok: true,
+          status: 200,
+          json: () => Promise.resolve({ flags: null }),
+        }),
+      );
+
+      await configurationRequestor.fetchAndStorePrecomputedFlags();
+
+      expect(fetchSpy).toHaveBeenCalledTimes(1);
+      expect(precomputedFlagStore.getKeys().length).toBe(0);
+    });
+  });
+});

src/precomputed-requestor.ts

@@ -3,7 +3,7 @@ import { hydrateConfigurationStore } from './configuration-store/configuration-s
 import { IHttpClient } from './http-client';
 import { PrecomputedFlag } from './interfaces';
 
-// Requests AND stores flag configurations
+// Requests AND stores precomputed flags, reuses the configuration store
 export default class ConfigurationRequestor {
   constructor(
     private readonly httpClient: IHttpClient,