Merchant API code sample to register a GCP project.

### C#

    // Copyright 2025 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.

    using System;
    using static MerchantApi.Authenticator;
    using Google.Api.Gax;
    using Google.Apis.Auth.OAuth2;
    using Google.Apis.Auth.OAuth2.Flows;
    using Google.Apis.Auth.OAuth2.Responses;
    using Google.Apis.Http;
    using Newtonsoft.Json;
    using Google.Shopping.Merchant.Accounts.V1;

    namespace MerchantApi
    {
        public class RegisterGcpSample
        {
            public void RegisterGcp(string developerEmail)
            {
                // Registers a specific developer's email address on the current GCP project
                Console.WriteLine("=================================================================");
                Console.WriteLine("Calling the RegisterGcp method");
                Console.WriteLine("=================================================================");

                // Authenticate using either oAuth or service account
                ICredential auth = Authenticator.Authenticate(
                    MerchantConfig.Load(),
                    // Passing the default scope for Merchant API: https://www.googleapis.com/auth/content
                    AccountsServiceClient.DefaultScopes[0]);

                // Create the DeveloperRegistrationServiceClient with the credentials
                DeveloperRegistrationServiceClientBuilder DeveloperRegistrationServiceClientBuilder = new DeveloperRegistrationServiceClientBuilder
                {
                    Credential = auth
                };
                DeveloperRegistrationServiceClient client = DeveloperRegistrationServiceClientBuilder.Build();

                // The name of the developer registration resource.
                // The format is: accounts/{merchantId}/developerRegistration
                // where {merchantId} is the ID of the merchant account.
                string name = "accounts/" + MerchantConfig.Load().MerchantId + "/developerRegistration";

                // Initialize request argument(s)
                RegisterGcpRequest request = new RegisterGcpRequest
                {
                    Name = name,
                    // Specify the email address of the developer to register
                    DeveloperEmail = developerEmail
                };

                // Call the RegisterGcp method
                DeveloperRegistration response = client.RegisterGcp(request);
                Console.WriteLine(JsonConvert.SerializeObject(response, Formatting.Indented));
            }

            internal static void Main(string[] args)
            {
                var registration = new RegisterGcpSample();
                string developerEmail = "YOUR_EMAIL";
                registration.RegisterGcp(developerEmail);
            }
        }
    }

### Go

    // Copyright 2025 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.

    // Package v1 provides examples for registering a GCP project with a developer email using the Merchant API.
    package v1

    import (
    	"context"
    	"fmt"
    	"log"

    	"cloud.google.com/go/shopping/merchant/accounts/apiv1/accountspb"

    	accounts "cloud.google.com/go/shopping/merchant/accounts/apiv1"
    	"google.golang.org/api/option"
    	"github.com/google/merchant-api-samples/go/collection"
    	"github.com/google/merchant-api-samples/go/examples/googleauth"
    )

    // The Merchant Center account ID.
    // Replace "accounts/1234567890" with your account ID.
    const accountNameForRegisterGcp = "accounts/1234567890/developerRegistration"

    // The email of the developer to register.
    // Replace with your email.
    const developerEmailForRegisterGcp = "YOUR_EMAIL_HERE"

    type registerGcpSample struct{}

    func init() {
    	// Use the new Add function from the collection package
    	if err := collection.Add("accounts.developerregistration.v1.register_gcp", &registerGcpSample{}); err != nil {
    		log.Fatalf("could not add example: %v", err)
    	}
    }

    func (s *registerGcpSample) Description() string {
    	return "Registers the GCP project with a developer email."
    }

    func (s *registerGcpSample) Execute() error {
    	ctx := context.Background()

    	// Authenticates with Google using the golang authentication library.
    	tokenSource, err := googleauth.AuthWithGoogle(ctx)
    	if err != nil {
    		return fmt.Errorf("failed to authenticate: %w", err)
    	}

    	// Creates a new Merchant API service.
    	accountsService, err := accounts.NewDeveloperRegistrationClient(ctx, option.WithTokenSource(tokenSource))
    	if err != nil {
    		return fmt.Errorf("unable to create Merchant API service: %w", err)
    	}

    	// Creates the request to register the GCP project with the developer email.
    	req := &accountspb.RegisterGcpRequest{
    		DeveloperEmail: developerEmailForRegisterGcp,
    		Name:           accountNameForRegisterGcp,
    	}

    	fmt.Println("Sending RegisterGcp request:")
    	// Calls the RegisterGcp method of the DeveloperRegistration service.
    	response, err := accountsService.RegisterGcp(ctx, req)
    	if err != nil {
    		return fmt.Errorf("unable to register GCP project: %w", err)
    	}

    	// Prints the response from the API.
    	fmt.Printf("Received response: %+v\n", response)
    	return nil
    }


### AppsScript

    // Copyright 2025 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.

    /**
     * Registers a specific developer's email address on the current GCP project
     * Note: every Apps Script project might be associated with a different default
     * GCP project.
     * Check https://developers.google.com/apps-script/guides/cloud-platform-projects
     * for more details.
     */
    function registerDeveloper() {
      // IMPORTANT:
      // Enable the Merchant API Accounts sub-API Advanced Service and call it
      // "MerchantApiAccounts"


      // Replace this with your Merchant Center ID.
      const accountId = '<ACCOUNT_ID>';

      // Replace this with your email address.
      const developerEmail = '<YOUR_EMAIL>';

      // Construct the parent resource name.
      const parent = 'accounts/' + accountId + '/developerRegistration';

      const requestBody = {
        'developerEmail': developerEmail,
      };
      try {
        console.log('Sending register GCP request');
        const response =
            MerchantApiAccounts.Accounts.DeveloperRegistration.registerGcp(
                requestBody, parent);
        console.log(response);
      } catch (e) {
        console.log('ERROR!');
        console.log(e);
      }
    }

### Java

    // Copyright 2025 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.

    package shopping.merchant.samples.accounts.developerregistration.v1;

    import com.google.api.gax.core.FixedCredentialsProvider;
    import com.google.auth.oauth2.GoogleCredentials;
    import com.google.shopping.merchant.accounts.v1.DeveloperRegistration;
    import com.google.shopping.merchant.accounts.v1.DeveloperRegistrationName;
    import com.google.shopping.merchant.accounts.v1.DeveloperRegistrationServiceClient;
    import com.google.shopping.merchant.accounts.v1.DeveloperRegistrationServiceSettings;
    import com.google.shopping.merchant.accounts.v1.RegisterGcpRequest;
    import shopping.merchant.samples.utils.Authenticator;
    import shopping.merchant.samples.utils.Config;

    /**
     * This class demonstrates how to register the GCP project used to call the Merchant API with a
     * developer email.
     */
    public class RegisterGcpSample {

      public static DeveloperRegistration registerGcp(Config config, String developerEmail) throws Exception {

        // Obtains OAuth token based on the user's configuration.
        GoogleCredentials credential = new Authenticator().authenticate();

        // Creates service settings using the credentials retrieved above.
        DeveloperRegistrationServiceSettings developerRegistrationServiceSettings =
            DeveloperRegistrationServiceSettings.newBuilder()
                .setCredentialsProvider(FixedCredentialsProvider.create(credential))
                .build();

        // Creates DeveloperRegistration name to identify the DeveloperRegistration.
        // The name has the format: accounts/{account}/developerRegistration
        String name =
            DeveloperRegistrationName.newBuilder()
                .setAccount(config.getAccountId().toString())
                .build()
                .toString();

        // Calls the API and propagates any network failures/errors.
        try (DeveloperRegistrationServiceClient developerRegistrationServiceClient =
            DeveloperRegistrationServiceClient.create(developerRegistrationServiceSettings)) {

          // Creates a request to register the GCP project with the developer email.
          RegisterGcpRequest request =
              RegisterGcpRequest.newBuilder().setName(name).setDeveloperEmail(developerEmail).build();

          System.out.println("Sending RegisterGcp request:");
          DeveloperRegistration response = developerRegistrationServiceClient.registerGcp(request);

          System.out.println(response);
          return response;
        }
      }

      public static void main(String[] args) throws Exception {
        Config config = Config.load();
        String developerEmail = "YOUR_EMAIL_HERE"; // Replace with your email
        registerGcp(config, developerEmail);
      }
    }

### Node.js

    // Copyright 2025 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.

    'use strict';
    const fs = require('fs');
    const authUtils = require('../../../authentication/authenticate.js');
    const {DeveloperRegistrationServiceClient} =
      require('@google-shopping/accounts').v1;

    /**
     * Registers the GCP project used to call the Merchant API with a developer email.
     */
    async function main() {
      try {
        // Replace with your developer email
        const developerEmail = 'developer@example.com';

        const config = authUtils.getConfig();

        // Read merchant_id from merchant-info.json
        const merchant_info = JSON.parse(
          fs.readFileSync(config.merchantInfoFile, 'utf8'),
        );
        const merchant_id = merchant_info.merchantId;

        // Construct parent. Parent is in the format of accounts/{merchant_id}
        const parent = 'accounts/' + merchant_id;

        // Construct name. Name is in the format of accounts/{merchant_id}/developerRegistration
        const name = parent + '/developerRegistration';

        // Get credentials
        const authClient = await authUtils.getOrGenerateUserCredentials();

        // Create options object for the client
        const options = {authClient: authClient};

        // Create client
        const developerRegistrationClient = new DeveloperRegistrationServiceClient(
          options,
        );

        // Construct request.
        const request = {
          name: name,
          developerEmail: developerEmail,
        };

        // Run request
        const response = await developerRegistrationClient.registerGcp(request);
        console.log('GCP project registered successfully:', response);
      } catch (error) {
        console.error(error.message);
      }
    }

    main();

### PHP

    <?php
    /**
     * Copyright 2025 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.
     */
    require_once __DIR__ . '/../../../../vendor/autoload.php';
    require_once __DIR__ . '/../../../Authentication/Authentication.php';
    require_once __DIR__ . '/../../../Authentication/Config.php';

    use Google\ApiCore\ApiException;
    use Google\Shopping\Merchant\Accounts\V1\Client\DeveloperRegistrationServiceClient;
    use Google\Shopping\Merchant\Accounts\V1\RegisterGcpRequest;

    /**
     * This class demonstrates how to register the GCP project used to call the
     * Merchant API with a developer email.
     */
    class RegisterGcpSample
    {
        /**
         * A helper function to create the name string for the
         * DeveloperRegistration.
         *
         * @param string $accountId The merchant account ID.
         * @return string The name, which has the format:
         *     `accounts/{account}/developerRegistration`
         */
        private static function getName(string $accountId): string
        {
            return sprintf("accounts/%s/developerRegistration", $accountId);
        }

        /**
         * Registers the GCP project with a developer email.
         *
         * @param array $config The configuration data for authentication and account ID.
         * @param string $developerEmail The email of the developer to register.
         */
        public static function registerGcpSample(array $config, string $developerEmail): void
        {
            // Obtains OAuth credentials from the configuration file.
            $credentials = Authentication::useServiceAccountOrTokenFile();

            // Creates a configuration object for the client.
            $options = ['credentials' => $credentials];

            // Creates the DeveloperRegistrationServiceClient.
            $developerRegistrationServiceClient = new DeveloperRegistrationServiceClient($options);

            // Creates the name of the developer registration to identify it.
            $name = self::getName($config['accountId']);

            // Calls the API and handles any network failures.
            try {
                // Creates a request to register the GCP project with the developer email.
                $request = new RegisterGcpRequest([
                    'name' => $name,
                    'developer_email' => $developerEmail
                ]);

                printf("Sending RegisterGcp request:%s", PHP_EOL);
                // The `registerGcp` method returns a `DeveloperRegistration` object
                // upon success.
                $response = $developerRegistrationServiceClient->registerGcp($request);
                print "Successfully registered developer email '$developerEmail' for account {$config['accountId']}.\n";
                print_r($response);
            } catch (ApiException $e) {
                printf("An error occurred: %s%s", $e->getMessage(), PHP_EOL);
            }
        }

        /**
         * Helper to execute the sample.
         */
        public function callSample(): void
        {
            $config = Config::generateConfig();
            // An email address for a developer to register for the API.
            $developerEmail = 'YOUR_EMAIL_HERE'; // Replace with your email
            self::registerGcpSample($config, $developerEmail);
        }
    }

    // Executes the sample.
    $sample = new RegisterGcpSample();
    $sample->callSample();

### Python

    # -*- coding: utf-8 -*-
    # Copyright 2025 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.

    """This example registers a GCP project with a developer email."""
    from examples.authentication import configuration
    from examples.authentication import generate_user_credentials
    from google.shopping.merchant_accounts_v1 import DeveloperRegistration
    from google.shopping.merchant_accounts_v1 import DeveloperRegistrationServiceClient
    from google.shopping.merchant_accounts_v1 import RegisterGcpRequest


    def register_gcp(
        account_id: str, developer_email: str
    ) -> DeveloperRegistration:
      """Registers the GCP project used to call the Merchant API with a developer email.

      Args:
        account_id: The ID of your Merchant Center account.
        developer_email: The email address of the developer to register.

      Returns:
        The created or updated DeveloperRegistration object.
      """
      # Get OAuth credentials.
      credentials = generate_user_credentials.main()

      # Create a client to the Developer Registration Service.
      client = DeveloperRegistrationServiceClient(credentials=credentials)

      # The name has the format: accounts/{account}/developerRegistration
      name = f"accounts/{account_id}/developerRegistration"

      # Create the request to register the GCP project.
      request = RegisterGcpRequest(
          name=name,
          developer_email=developer_email,
      )

      # Make the API call and handle potential errors.
      try:
        print("Sending RegisterGcp request:")
        response = client.register_gcp(request=request)
        print("Registered GCP project successfully:")
        print(response)
        return response
      except RuntimeError as e:
        print(f"An error occurred: {e}")
        raise


    if __name__ == "__main__":

      # Your Merchant Center account ID.
      # This can be found in the Merchant Center UI.
      _account_id = configuration.Configuration().read_merchant_info()

      # The developer email to associate with the GCP project.
      _developer_email = "YOUR_EMAIL_HERE"

      register_gcp(_account_id, _developer_email)