google-merchant-api

Google Merchant API

Programmatically manage Google Merchant Center accounts, products, inventory, promotions, and more.

API Landscape

Google provides two APIs for Merchant Center. The Merchant API (v1) is the current standard. The Content API for Shopping (v2.1) is the legacy API, sunsetting August 18, 2026.

Aspect	Merchant API (v1)	Content API for Shopping (v2.1)
Base URL	https://merchantapi.googleapis.com	https://shoppingcontent.googleapis.com
Transport	gRPC (default) + REST	REST only
Status	Active, GA	Sunset August 18, 2026
Design	Modular sub-APIs	Monolithic
Batching	Async / HTTP batching	customBatch methods

Always prefer the Merchant API for new integrations. Only use Content API if maintaining legacy code or if a feature hasn't migrated yet.

Authentication

Both APIs use Google OAuth 2.0. Two approaches:

Service Account (server-to-server)

Best for automated backends. Create a service account in Google Cloud Console, download the JSON key, and grant it access in Merchant Center.

// Node.js with google-auth-library
const { GoogleAuth } = require('google-auth-library');

const auth = new GoogleAuth({
  keyFile: 'service-account-key.json',
  scopes: ['https://www.googleapis.com/auth/content'],
});
const client = await auth.getClient();
const token = await client.getAccessToken();

# Python with google-auth
from google.oauth2 import service_account

credentials = service_account.Credentials.from_service_account_file(
    'service-account-key.json',
    scopes=['https://www.googleapis.com/auth/content']
)

OAuth 2.0 Client (user-interactive)

Best for apps acting on behalf of merchants. Requires consent flow.

// Node.js OAuth2 flow
const { OAuth2Client } = require('google-auth-library');

const oauth2Client = new OAuth2Client(
  CLIENT_ID,
  CLIENT_SECRET,
  REDIRECT_URI
);

// Generate auth URL
const authUrl = oauth2Client.generateAuthUrl({
  access_type: 'offline',
  scope: ['https://www.googleapis.com/auth/content'],
});

// Exchange code for tokens
const { tokens } = await oauth2Client.getToken(code);
oauth2Client.setCredentials(tokens);