Month: December 2025

Prerequiste

• add JWT token to service account
• add service account to Merchant API user
• set the service account as developer
• In Google Cloud Console enable Content API for Shopping for the project that owns the service account. Google for Developers
• In Merchant Center, get the numeric merchantId shown in the Merchant Center settings (you’ll pass this to API calls). Google for Developers

Create simple Node project

mkdir gmc-content-demo && cd gmc-content-demo
npm init -y
npm install googleapis google-auth-library @google-shopping/products

Put your service account JSON somewhere safe

Save your downloaded JSON key file as service-account.json (or set path via env var). Never commit it to source control.

Create insert-product.js file

// insert-product-input.js
'use strict';

const path = require('path');
const { GoogleAuth } = require('google-auth-library');
const { ProductInputsServiceClient } = require('@google-shopping/products').v1;

async function main() {
  const merchantId = 'MERCHANT_ID';           // e.g. "123456789"
  const dataSourceId = 'DATA_SOURCE_ID';       // feed/data source ID
  const offerId = 'sku-12345';
  const productId = `en~online~${offerId}`;        // language~label~offerId

  // Full resource name for product input
  const productInputName = `accounts/${merchantId}/productInputs/${productId}`;

  // Authenticate
  const auth = new GoogleAuth({
    keyFile: path.join(__dirname, 'service-account.json'),
    scopes: ['https://www.googleapis.com/auth/content']
  });

  const authClient = await auth.getClient();

  // Create client
  const client = new ProductInputsServiceClient({ authClient });

  // Product attributes
  const productAttributes = {
    title: "New Jacket Product (Inserted via API)",
    description: "A stylish jacket added using ProductInputsServiceClient.",
    link: "https://example.com/jacket",
    imageLink: "https://example.com/jacket.jpg",
    availability: "IN_STOCK",
    condition: "NEW",
    price: { amountMicros: 49900000, currencyCode: "USD" },
    gtin: ["9780007350896"],
    brand: "MyBrand"
  };


  // Build productInput 
  const productInput = {
    name: productInputName,
    contentLanguage: 'en',
    offerId: "irrestistible-offer-12345",
    feedLabel: 'GB', // Check the feed label of the data source in the Merchant API account
    productAttributes
  };

  try {
    console.log("Inserting ProductInput…");

    const dataSource = `accounts/${merchantId}/dataSources/${dataSourceId}`;
    const parent = `accounts/${merchantId}`;

    const [response] = await client.insertProductInput({
      parent,
      dataSource,
      productInput
    });

    console.log("Product inserted successfully:");
    console.log(JSON.stringify(response, null, 2));

  } catch (err) {
    console.error("Insert failed:", err);
  } finally {
    if (client.close) await client.close();
  }
}

main().catch(err => {
  console.error("Fatal error", err);
});

Other examples

https://developers.google.com/merchant/api/samples/insert-product-input#node.js

In postman

You’ll need to generate a self signed JWT, you can use jwt.io to create the token

Follow the steps here:

https://docs.cloud.google.com/docs/authentication/token-types#sa-jwts

You can then use that JWT token that you pass in assertion header to get an access token that you can use to make your query with.