chore(api): log growthbook initialization failures (#59889)

Co-authored-by: Mrugesh Mohapatra <1884376+raisedadead@users.noreply.github.com>
Co-authored-by: Shaun Hamilton <shauhami020@gmail.com>

api/src/plugins/growth-book.test.ts

@@ -0,0 +1,29 @@
+import Fastify, { type FastifyInstance } from 'fastify';
+import growthBook from './growth-book';
+
+const captureException = jest.fn();
+
+describe('growth-book', () => {
+  let fastify: FastifyInstance;
+  beforeAll(() => {
+    fastify = Fastify();
+    // @ts-expect-error we're mocking the Sentry plugin
+    fastify.Sentry = { captureException };
+  });
+
+  afterAll(async () => {
+    await fastify.close();
+  });
+
+  it('should log the error if the GrowthBook initialization fails', async () => {
+    const spy = jest.spyOn(fastify.log, 'error');
+
+    await fastify.register(growthBook, {
+      apiHost: 'invalid-url',
+      clientKey: 'invalid-key'
+    });
+
+    expect(spy).toHaveBeenCalled();
+    expect(captureException).toHaveBeenCalled();
+  });
+});

api/src/plugins/growth-book.ts

@@ -2,9 +2,20 @@ import { GrowthBook, Options } from '@growthbook/growthbook';
 import { FastifyPluginAsync } from 'fastify';
 import fp from 'fastify-plugin';
 
+declare module 'fastify' {
+  interface FastifyInstance {
+    gb: GrowthBook;
+  }
+}
+
 const growthBook: FastifyPluginAsync<Options> = async (fastify, options) => {
   const gb = new GrowthBook(options);
-  await gb.init({ timeout: 3000 });
+  const res = await gb.init({ timeout: 3000 });
+
+  if (res.error) {
+    fastify.log.error(res.error, 'Failed to initialize GrowthBook');
+    fastify.Sentry.captureException(res.error);
+  }
 
   fastify.decorate('gb', gb);