googleapis · 64johnlee · Jun 6, 2026 · Jun 6, 2026
@@ -39,7 +39,16 @@ export async function throwErrorIfNotOK(response: Response | undefined) {
   if (!response.ok) {
     const status: number = response.status;
     const statusText: string = response.statusText;
-    const errorBody = await response.json();
+    const responseText = await response.text();
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    let errorBody: any;
+    try {
+      errorBody = JSON.parse(responseText);
+    } catch {
+      throw new GoogleGenerativeAIError(
+        `got status: ${status} ${statusText}. Response body is not valid JSON: ${responseText.slice(0, 500)}`
+      );
+    }
     const errorMessage = `got status: ${status} ${statusText}. ${JSON.stringify(
       errorBody
     )}`;

@@ -55,7 +55,9 @@ export async function postRequest({
   requestOptions?: RequestOptions;
   apiVersion?: string;
 }): Promise<Response | undefined> {
-  const vertexBaseEndpoint = apiEndpoint ?? `${region}-${API_BASE_PATH}`;
+  const vertexBaseEndpoint =
+    apiEndpoint ??
+    (region === 'global' ? API_BASE_PATH : `${region}-${API_BASE_PATH}`);
 
   let vertexEndpoint = `https://${vertexBaseEndpoint}/${apiVersion}/${resourcePath}:${resourceMethod}`;
 

@@ -33,7 +33,10 @@ import {
   UNARY_RESPONSE_MISSING_ROLE_INDEX,
 } from './test_data';
 import * as PostFetchFunctions from '../post_fetch_processing';
-import {aggregateResponses} from '../post_fetch_processing';
+import {
+  aggregateResponses,
+  throwErrorIfNotOK,
+} from '../post_fetch_processing';
 import {generateContent, generateContentStream} from '../generate_content';
 import {countTokens} from '../count_tokens';
 
@@ -180,6 +183,47 @@ describe('processStream', () => {
   });
 });
 
+describe('throwErrorIfNotOK', () => {
+  it('non-JSON response body should throw descriptive error instead of JSON parse error', async () => {
+    const htmlBody = '<!DOCTYPE html><html><body>Not Found</body></html>';
+    const response = new Response(htmlBody, {
+      status: 404,
+      statusText: 'Not Found',
+      headers: {'Content-Type': 'text/html'},
+    });
+    await expectAsync(throwErrorIfNotOK(response)).toBeRejectedWithError(
+      /Response body is not valid JSON/
+    );
+  });
+
+  it('valid JSON 4xx response body should throw ClientError', async () => {
+    const errorBody = {
+      error: {
+        message: 'Resource not found',
+        code: 404,
+        status: 'NOT_FOUND',
+        details: [],
+      },
+    };
+    const response = new Response(JSON.stringify(errorBody), {
+      status: 404,
+      statusText: 'Not Found',
+      headers: {'Content-Type': 'application/json'},
+    });
+    await expectAsync(throwErrorIfNotOK(response)).toBeRejectedWithError(
+      /got status: 404/
+    );
+  });
+
+  it('OK response should not throw', async () => {
+    const response = new Response('{}', {
+      status: 200,
+      statusText: 'OK',
+    });
+    await expectAsync(throwErrorIfNotOK(response)).toBeResolved();
+  });
+});
+
 describe('processCountTokenResponse', () => {
   it('multiple contents, processCountTokenResponse should return faithful response', async () => {
     const fetchResult = new Response(

@@ -166,6 +166,31 @@ describe('postRequest', () => {
     expect(actualHeaders.get('Content-Type')).toEqual('application/json');
   });
 
+  it('global region without apiEndpoint should use base endpoint without region prefix', async () => {
+    await postRequest({
+      region: 'global',
+      resourcePath: RESOURCE_PATH,
+      resourceMethod: RESOURCE_METHOD,
+      token: TOKEN,
+      data: data,
+    });
+    const actualUrl: string = fetchSpy.calls.mostRecent().args[0];
+    expect(actualUrl).toContain('aiplatform.googleapis.com');
+    expect(actualUrl).not.toContain('global-aiplatform.googleapis.com');
+  });
+
+  it('regional endpoint should still prepend region prefix', async () => {
+    await postRequest({
+      region: 'us-central1',
+      resourcePath: RESOURCE_PATH,
+      resourceMethod: RESOURCE_METHOD,
+      token: TOKEN,
+      data: data,
+    });
+    const actualUrl: string = fetchSpy.calls.mostRecent().args[0];
+    expect(actualUrl).toContain('us-central1-aiplatform.googleapis.com');
+  });
+
   it('set both custom header and apiClient, should prioritize custom headers if sent to external endpoint', async () => {
     const requestOptions: RequestOptions = {
       customHeaders: new Headers({

@@ -49,7 +49,9 @@ export class ApiClient {
   }
 
   getBaseUrl() {
-    return `https://${this.location}-aiplatform.googleapis.com/${this.apiVersion}`;
+    const locationPrefix =
+      this.location === 'global' ? '' : `${this.location}-`;
+    return `https://${locationPrefix}aiplatform.googleapis.com/${this.apiVersion}`;
   }
 
   getBaseResourePath() {

@@ -0,0 +1,50 @@
+/**
+ * @license
+ * Copyright 2024 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import {GoogleAuth} from 'google-auth-library';
+import {ApiClient} from '../api_client';
+
+function makeClient(location: string): ApiClient {
+  return new ApiClient(
+    'test-project',
+    location,
+    'v1',
+    {} as unknown as GoogleAuth
+  );
+}
+
+describe('ApiClient.getBaseUrl', () => {
+  it('global location should return endpoint without region prefix', () => {
+    const client = makeClient('global');
+    expect(client.getBaseUrl()).toBe('https://aiplatform.googleapis.com/v1');
+    expect(client.getBaseUrl()).not.toContain('global-');
+  });
+
+  it('regional location should return endpoint with region prefix', () => {
+    const client = makeClient('us-central1');
+    expect(client.getBaseUrl()).toBe(
+      'https://us-central1-aiplatform.googleapis.com/v1'
+    );
+  });
+
+  it('eu-west4 location should return endpoint with correct region prefix', () => {
+    const client = makeClient('eu-west4');
+    expect(client.getBaseUrl()).toBe(
+      'https://eu-west4-aiplatform.googleapis.com/v1'
+    );
+  });
+});