[FSSDK-11497] fire config update events synchronously (#1043)

fire the project config updates synchronously. this will allow the optimizely class to propagate the initial project config synchronously to all sub components. This can be useful when the client is initialized with a datafile. One downside is, the update event handler needs to be registered before calling start() on the config manager, but since we only use the config manager internally, we can maintain that.

Author: raju-opti

lib/project_config/project_config_manager.spec.ts

@@ -121,24 +121,17 @@ describe('ProjectConfigManagerImpl', () => {
       expect(manager.getState()).toBe(ServiceState.Running);
     });
 
-    it('should call onUpdate listeners registered before or after start() with the project config after resolving onRunning()', async () => {
+    it('should call onUpdate listeners registered before start() with the project config', async () => {
       const logger = getMockLogger();
       const manager = new ProjectConfigManagerImpl({ logger, datafile: testData.getTestProjectConfig()});
-      const listener1 = vi.fn();
-      manager.onUpdate(listener1);
+      const listener = vi.fn();
+      manager.onUpdate(listener);
       manager.start();
-      const listener2 = vi.fn();
-      manager.onUpdate(listener2);
-      expect(listener1).not.toHaveBeenCalled();
-      expect(listener2).not.toHaveBeenCalledOnce();
 
       await manager.onRunning();
 
-      expect(listener1).toHaveBeenCalledOnce();
-      expect(listener2).toHaveBeenCalledOnce();
-
-      expect(listener1).toHaveBeenCalledWith(createProjectConfig(testData.getTestProjectConfig()));
-      expect(listener2).toHaveBeenCalledWith(createProjectConfig(testData.getTestProjectConfig()));
+      expect(listener).toHaveBeenCalledOnce();
+      expect(listener).toHaveBeenCalledWith(createProjectConfig(testData.getTestProjectConfig()));
     });
 
     it('should return the correct config from getConfig() both before or after onRunning() resolves', async () => {
@@ -187,8 +180,8 @@ describe('ProjectConfigManagerImpl', () => {
           const listener = vi.fn();
 
           const manager = new ProjectConfigManagerImpl({ datafile: testData.getTestProjectConfig(), datafileManager });
-          manager.start();
           manager.onUpdate(listener);
+          manager.start();
           await expect(manager.onRunning()).resolves.not.toThrow();
           expect(listener).toHaveBeenCalledWith(createProjectConfig(testData.getTestProjectConfig()));
         });
@@ -309,11 +302,12 @@ describe('ProjectConfigManagerImpl', () => {
 
       const datafile = testData.getTestProjectConfig();
       const manager = new ProjectConfigManagerImpl({ datafile, datafileManager });
-      manager.start();
 
       const listener = vi.fn();
       manager.onUpdate(listener);
 
+      manager.start();
+
       expect(manager.getConfig()).toEqual(createProjectConfig(datafile));
       await manager.onRunning();
       expect(manager.getConfig()).toEqual(createProjectConfig(datafile));
@@ -334,11 +328,12 @@ describe('ProjectConfigManagerImpl', () => {
       const logger = getMockLogger();
       const datafile = testData.getTestProjectConfig();
       const manager = new ProjectConfigManagerImpl({ logger, datafile, datafileManager });
-      manager.start();
 
       const listener = vi.fn();
       manager.onUpdate(listener);
 
+      manager.start();
+
       expect(manager.getConfig()).toEqual(createProjectConfig(testData.getTestProjectConfig()));
       await manager.onRunning();
       expect(manager.getConfig()).toEqual(createProjectConfig(testData.getTestProjectConfig()));
@@ -379,11 +374,12 @@ describe('ProjectConfigManagerImpl', () => {
 
       const datafile = testData.getTestProjectConfig();
       const manager = new ProjectConfigManagerImpl({ datafile, datafileManager });
-      manager.start();
 
       const listener = vi.fn();
       manager.onUpdate(listener);
 
+      manager.start();
+
       expect(manager.getConfig()).toEqual(createProjectConfig(datafile));
       await manager.onRunning();
       expect(manager.getConfig()).toEqual(createProjectConfig(datafile));
@@ -401,11 +397,12 @@ describe('ProjectConfigManagerImpl', () => {
       const datafileManager = getMockDatafileManager({});
 
       const manager = new ProjectConfigManagerImpl({ datafile });
-      manager.start();
 
       const listener = vi.fn();
       const dispose = manager.onUpdate(listener);
 
+      manager.start();
+
       await manager.onRunning();
       expect(listener).toHaveBeenNthCalledWith(1, createProjectConfig(datafile));
 
@@ -420,11 +417,12 @@ describe('ProjectConfigManagerImpl', () => {
       const datafile = testData.getTestProjectConfig();
 
       const manager = new ProjectConfigManagerImpl({ datafile: JSON.stringify(datafile) });
-      manager.start();
 
       const listener = vi.fn();
       manager.onUpdate(listener);
 
+      manager.start();
+
       await manager.onRunning();
       expect(listener).toHaveBeenCalledWith(createProjectConfig(datafile));
       expect(manager.getConfig()).toEqual(createProjectConfig(datafile));

lib/project_config/project_config_manager.ts

@@ -18,7 +18,6 @@ import { createOptimizelyConfig } from './optimizely_config';
 import {  OptimizelyConfig } from '../shared_types';
 import { DatafileManager } from './datafile_manager';
 import { ProjectConfig, toDatafile, tryCreatingProjectConfig } from './project_config';
-import { scheduleMicrotask } from '../utils/microtask';
 import { Service, ServiceState, BaseService } from '../service';
 import { Consumer, Fn, Transformer } from '../utils/type';
 import { EventEmitter } from '../utils/event_emitter/event_emitter';
@@ -166,9 +165,7 @@ export class ProjectConfigManagerImpl extends BaseService implements ProjectConf
       if (this.projectConfig?.revision !== config.revision) {
         this.projectConfig = config;
         this.optimizelyConfig = undefined;
-        scheduleMicrotask(() => {
-          this.eventEmitter.emit('update', config);
-        }) 
+        this.eventEmitter.emit('update', config);
       }
     } catch (err) {
       this.logger?.error(err);