feat: add feature experiment support in web script

packages/experiment-browser/src/factory.ts

@@ -1,11 +1,14 @@
 import { AnalyticsConnector } from '@amplitude/analytics-connector';
+import { safeGlobal } from '@amplitude/experiment-core';
 
 import { Defaults, ExperimentConfig } from './config';
 import { ExperimentClient } from './experimentClient';
 import { AmplitudeIntegrationPlugin } from './integration/amplitude';
 import { DefaultUserProvider } from './providers/default';
 
-const instances = {};
+// Global instances for debugging.
+safeGlobal.experimentInstances = {};
+const instances = safeGlobal.experimentInstances;
 
 const getInstanceName = (config: ExperimentConfig): string => {
   return config?.instanceName || Defaults.instanceName;
@@ -18,7 +21,7 @@ const getInstanceName = (config: ExperimentConfig): string => {
  * @param apiKey The deployment API Key
  * @param config See {@link ExperimentConfig} for config options
  */
-const initialize = (
+export const initialize = (
   apiKey: string,
   config?: ExperimentConfig,
 ): ExperimentClient => {
@@ -52,7 +55,7 @@ const initialize = (
  * @param apiKey The deployment API Key
  * @param config See {@link ExperimentConfig} for config options
  */
-const initializeWithAmplitudeAnalytics = (
+export const initializeWithAmplitudeAnalytics = (
   apiKey: string,
   config?: ExperimentConfig,
 ): ExperimentClient => {

packages/experiment-browser/src/index.ts

@@ -11,7 +11,11 @@ export {
   AmplitudeAnalyticsProvider,
 } from './providers/amplitude';
 export { AmplitudeIntegrationPlugin } from './integration/amplitude';
-export { Experiment } from './factory';
+export {
+  Experiment,
+  initialize,
+  initializeWithAmplitudeAnalytics,
+} from './factory';
 export { StubExperimentClient } from './stubClient';
 export { ExperimentClient } from './experimentClient';
 export { Client, FetchOptions } from './types/client';

packages/experiment-tag/src/experiment.ts

@@ -5,13 +5,15 @@ import {
   getGlobalScope,
   isLocalStorageAvailable,
 } from '@amplitude/experiment-core';
+import { safeGlobal } from '@amplitude/experiment-core';
 import {
   Experiment,
   ExperimentUser,
   Variant,
   Variants,
   AmplitudeIntegrationPlugin,
 } from '@amplitude/experiment-js-client';
+import * as FeatureExperiment from '@amplitude/experiment-js-client';
 import mutate, { MutationController } from 'dom-mutator';
 
 import { getInjectUtils } from './inject-utils';
@@ -24,6 +26,8 @@ import {
   concatenateQueryParamsOf,
 } from './util';
 
+safeGlobal.Experiment = FeatureExperiment;
+
 const appliedInjections: Set<string> = new Set();
 const appliedMutations: MutationController[] = [];
 let previousUrl: string | undefined;

packages/experiment-tag/test/experiment.test.ts

@@ -1,4 +1,5 @@
 import * as coreUtil from '@amplitude/experiment-core';
+import { safeGlobal } from '@amplitude/experiment-core';
 import { ExperimentClient } from '@amplitude/experiment-js-client';
 import { initializeExperiment } from 'src/experiment';
 import * as experiment from 'src/experiment';
@@ -736,3 +737,7 @@ describe('initializeExperiment', () => {
     expect(mockExposure).not.toHaveBeenCalled();
   });
 });
+
+test('feature experiment on global Experiment object', () => {
+  expect(safeGlobal.Experiment).toBeDefined();
+});