test: remove e2e test for onLog and add unit test

packages/app/__tests__/app.test.ts

@@ -1,4 +1,4 @@
-import { describe, expect, it } from '@jest/globals';
+import { jest, describe, expect, it } from '@jest/globals';
 
 import {
   deleteApp,
@@ -9,6 +9,7 @@ import {
   getApp,
   setLogLevel,
 } from '../lib';
+import { Logger } from '../lib/internal/logger';
 
 describe('App', function () {
   describe('modular', function () {
@@ -39,5 +40,22 @@ describe('App', function () {
     it('`setLogLevel` function is properly exposed to end user', function () {
       expect(setLogLevel).toBeDefined();
     });
+
+    it('`onLog()` is called when using Logger (currently only VertexAI uses `onLog()`)', function () {
+      const logger = new Logger('@firebase/vertexai');
+      const spy2 = jest.fn();
+
+      onLog(spy2);
+      logger.info('test');
+
+      expect(spy2).toHaveBeenCalledWith(
+        expect.objectContaining({
+          args: ['test'],
+          level: 'info',
+          message: 'test',
+          type: '@firebase/vertexai',
+        }),
+      );
+    });
   });
 });

packages/app/lib/internal/logger.js

@@ -34,6 +34,17 @@ const LogLevel = {
   SILENT: 5,
 };
 
+// mimic the LogLevel in firebase-js-sdk TS
+const reverseLogLevel = obj => {
+  const reversed = {};
+  for (const [key, value] of Object.entries(obj)) {
+    reversed[value] = key;
+  }
+  return reversed;
+};
+
+const LogLevelReversed = reverseLogLevel(LogLevel);
+
 /**
  * By default, `console.debug` is not displayed in the developer console (in
  * chrome). To avoid forcing users to have to opt-in to these logs twice
@@ -208,7 +219,7 @@ export function setUserLogHandler(logCallback, options) {
           .join(' ');
         if (level >= (customLogLevel ?? instance.logLevel)) {
           logCallback({
-            level: LogLevel[level].toLowerCase(),
+            level: LogLevelReversed[level].toLowerCase(),
             message,
             args,
             type: instance.name,

packages/app/lib/modular/index.d.ts

@@ -25,13 +25,23 @@ export function registerVersion(
 ): Promise<void>;
 
 /**
- * Sets log handler for all Firebase SDKs.
+ * Sets log handler for all Firebase SDKs. Currently only supported on VertexAI.
  * @param logCallback - The callback function to handle logs.
  * @param options - Optional settings for log handling.
- * @returns Promise<void>
- * @throws Error - onLog is only supported on Web
+ * @returns <void>
  */
-export function onLog(logCallback: (logData: any) => void, options?: any): Promise<void>;
+
+interface LogCallbackParams {
+  level: LogLevelString;
+  message: string;
+  args: unknown[];
+  type: string;
+}
+
+export function onLog(
+  logCallback: (callbackParams: LogCallbackParams) => void,
+  options?: any,
+): void;
 
 /**
  * Gets the list of all initialized apps.