feat: Use enhanced logger support for browser SDK.

Author: kinyoklion

packages/sdk/browser/src/BrowserClient.ts

@@ -1,6 +1,7 @@
 import {
   AutoEnvAttributes,
   base64UrlEncode,
+  BasicLogger,
   LDClient as CommonClient,
   Configuration,
   createSafeLogger,
@@ -98,15 +99,18 @@ export class BrowserClient extends LDClientImpl implements LDClient {
     // Overrides the default logger from the common implementation.
     const logger =
       customLogger ??
-      createSafeLogger({
-        // eslint-disable-next-line no-console
-        debug: debug ? console.debug : () => {},
-        // eslint-disable-next-line no-console
-        info: console.info,
-        // eslint-disable-next-line no-console
-        warn: console.warn,
-        // eslint-disable-next-line no-console
-        error: console.error,
+      new BasicLogger({
+        destination: {
+          // eslint-disable-next-line no-console
+          debug: console.debug,
+          // eslint-disable-next-line no-console
+          info: console.info,
+          // eslint-disable-next-line no-console
+          warn: console.warn,
+          // eslint-disable-next-line no-console
+          error: console.error,
+        },
+        level: debug ? 'debug' : 'info',
       });
 
     // TODO: Use the already-configured baseUri from the SDK config. SDK-560

packages/sdk/browser/src/index.ts

@@ -12,6 +12,8 @@
  */
 import {
   AutoEnvAttributes,
+  BasicLogger,
+  BasicLoggerOptions,
   EvaluationSeriesContext,
   EvaluationSeriesData,
   Hook,
@@ -84,3 +86,54 @@ export function initialize(clientSideId: string, options?: LDOptions): LDClient
   // AutoEnvAttributes are not supported yet in the browser SDK.
   return new BrowserClient(clientSideId, AutoEnvAttributes.Disabled, options);
 }
+
+/**
+ * Provides a simple {@link LDLogger} implementation.
+ *
+ * This logging implementation uses a simple format that includes only the log level
+ * and the message text. By default the output is written to `console.error`.
+ *
+ * To use the logger created by this function, put it into {@link LDOptions.logger}. If
+ * you do not set {@link LDOptions.logger} to anything, the SDK uses a default logger
+ * that will log "info" level and higher priorty messages and it will log messages to
+ * console.info, console.warn, and console.error.
+ *
+ * @param options Configuration for the logger. If no options are specified, the
+ *   logger uses `{ level: 'info' }`.
+ *
+ * @example
+ * This example shows how to use `basicLogger` in your SDK options to enable console
+ * logging only at `warn` and `error` levels.
+ * ```javascript
+ *   const ldOptions = {
+ *     logger: basicLogger({ level: 'warn' }),
+ *   };
+ * ```
+ *
+ * @example
+ * This example shows how to use `basicLogger` in your SDK options to cause all
+ * log output to go to `console.log`
+ * ```javascript
+ *   const ldOptions = {
+ *     logger: ld.basicLogger({ destination: console.log }),
+ *   };
+ * ```
+ *
+ *  * @example
+ * The configuration also allows you to control the destination for each log level.
+ * ```javascript
+ *   const ldOptions = {
+ *     logger: ld.basicLogger({
+ *       destination: {
+ *         debug: console.debug,
+ *         info: console.info,
+ *         warn: console.warn,
+ *         error:console.error
+ *       }
+ *     }),
+ *   };
+ * ```
+ */
+export function basicLogger(options: BasicLoggerOptions): LDLogger {
+  return new BasicLogger(options);
+}

packages/shared/sdk-client/src/api/LDOptions.ts

@@ -126,7 +126,10 @@ export interface LDOptions {
    * @remarks
    * Set a custom {@link LDLogger} if you want full control of logging behavior.
    *
-   * @defaultValue A {@link BasicLogger} which outputs to the console at `info` level.
+   * @defaultValue The default logging implementation will varybased on platform. For the browser
+   * the default logger will log "info" level and higher priorty messages and it will log messages to
+   * console.info, console.warn, and console.error. Other platforms may use a `BasicLogger` instance
+   * also defaulted to the "info" level.
    */
   logger?: LDLogger;