fix: Handle default flush interval for browser SDK.

Author: kinyoklion

packages/sdk/browser/__tests__/options.test.ts

@@ -2,7 +2,10 @@ import { jest } from '@jest/globals';
 
 import { LDLogger } from '@launchdarkly/js-client-sdk-common';
 
-import validateOptions, { filterToBaseOptions } from '../src/options';
+import validateBrowserOptions, {
+  filterToBaseOptionsWithDefaults,
+  withBrowserDefaults,
+} from '../src/options';
 
 let logger: LDLogger;
 
@@ -16,7 +19,7 @@ beforeEach(() => {
 });
 
 it('logs no warnings when all configuration is valid', () => {
-  validateOptions(
+  validateBrowserOptions(
     {
       fetchGoals: true,
       eventUrlTransformer: (url: string) => url,
@@ -31,7 +34,7 @@ it('logs no warnings when all configuration is valid', () => {
 });
 
 it('warns for invalid configuration', () => {
-  validateOptions(
+  validateBrowserOptions(
     {
       // @ts-ignore
       fetchGoals: 'yes',
@@ -50,8 +53,8 @@ it('warns for invalid configuration', () => {
   );
 });
 
-it('applies default options', () => {
-  const opts = validateOptions({}, logger);
+it('applies default browser-specific options', () => {
+  const opts = validateBrowserOptions({}, logger);
 
   expect(opts.fetchGoals).toBe(true);
   expect(opts.eventUrlTransformer).toBeDefined();
@@ -69,9 +72,29 @@ it('filters to base options', () => {
     eventUrlTransformer: (url: string) => url,
   };
 
-  const baseOpts = filterToBaseOptions(opts);
+  const baseOpts = filterToBaseOptionsWithDefaults(opts);
   expect(baseOpts.debug).toBe(false);
   expect(Object.keys(baseOpts).length).toEqual(1);
   expect(baseOpts).not.toHaveProperty('fetchGoals');
   expect(baseOpts).not.toHaveProperty('eventUrlTransformer');
 });
+
+it('applies default overrides to common config flushInterval', () => {
+  const opts = {};
+  const result = withBrowserDefaults(opts);
+  expect(result.flushInterval).toEqual(2);
+});
+
+it('does not override common config flushInterval if it is set', () => {
+  const opts = {
+    flushInterval: 15,
+  };
+  const result = withBrowserDefaults(opts);
+  expect(result.flushInterval).toEqual(15);
+});
+
+it('includes overridden defaults after filtering to base options', () => {
+  const opts = {};
+  const result = filterToBaseOptionsWithDefaults(withBrowserDefaults(opts));
+  expect(result.flushInterval).toEqual(2);
+});

packages/sdk/browser/src/BrowserClient.ts

@@ -21,7 +21,7 @@ import { BrowserIdentifyOptions as LDIdentifyOptions } from './BrowserIdentifyOp
 import { registerStateDetection } from './BrowserStateDetector';
 import GoalManager from './goals/GoalManager';
 import { Goal, isClick } from './goals/Goals';
-import validateOptions, { BrowserOptions, filterToBaseOptions } from './options';
+import validateBrowserOptions, { BrowserOptions, filterToBaseOptionsWithDefaults } from './options';
 import BrowserPlatform from './platform/BrowserPlatform';
 
 /**
@@ -116,13 +116,16 @@ export class BrowserClient extends LDClientImpl implements LDClient {
     const baseUrl = options.baseUri ?? 'https://clientsdk.launchdarkly.com';
 
     const platform = overridePlatform ?? new BrowserPlatform(logger);
-    const validatedBrowserOptions = validateOptions(options, logger);
+    // Only the browser-specific options are in validatedBrowserOptions.
+    const validatedBrowserOptions = validateBrowserOptions(options, logger);
+    // The base options are in baseOptionsWithDefaults.
+    const baseOptionsWithDefaults = filterToBaseOptionsWithDefaults({ ...options, logger });
     const { eventUrlTransformer } = validatedBrowserOptions;
     super(
       clientSideId,
       autoEnvAttributes,
       platform,
-      filterToBaseOptions({ ...options, logger }),
+      baseOptionsWithDefaults,
       (
         flagManager: FlagManager,
         configuration: Configuration,

packages/sdk/browser/src/options.ts

@@ -73,25 +73,28 @@ const validators: { [Property in keyof BrowserOptions]: TypeValidator | undefine
   streaming: TypeValidators.Boolean,
 };
 
-export function filterToBaseOptions(opts: BrowserOptions): LDOptionsBase {
-  const baseOptions: LDOptionsBase = { ...opts };
+function withBrowserDefaults(opts: BrowserOptions): BrowserOptions {
+  const output = { ...opts };
+  output.flushInterval ??= DEFAULT_FLUSH_INTERVAL_SECONDS;
+  return output;
+}
+
+export function filterToBaseOptionsWithDefaults(opts: BrowserOptions): LDOptionsBase {
+  const baseOptionsWithDefaults: LDOptionsBase = withBrowserDefaults(opts);
 
   // Remove any browser specific configuration keys so we don't get warnings from
   // the base implementation for unknown configuration.
   Object.keys(optDefaults).forEach((key) => {
-    delete (baseOptions as any)[key];
+    delete (baseOptionsWithDefaults as any)[key];
   });
-  return baseOptions;
-}
-
-function applyBrowserDefaults(opts: BrowserOptions) {
-  // eslint-disable-next-line no-param-reassign
-  opts.flushInterval ??= DEFAULT_FLUSH_INTERVAL_SECONDS;
+  return baseOptionsWithDefaults;
 }
 
-export default function validateOptions(opts: BrowserOptions, logger: LDLogger): ValidatedOptions {
+export default function validateBrowserOptions(
+  opts: BrowserOptions,
+  logger: LDLogger,
+): ValidatedOptions {
   const output: ValidatedOptions = { ...optDefaults };
-  applyBrowserDefaults(output);
 
   Object.entries(validators).forEach((entry) => {
     const [key, validator] = entry as [keyof BrowserOptions, TypeValidator];