Create a service account HMAC key

Create a service account HMAC key.

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For detailed documentation that includes this code sample, see the following:

Code sample

C++

For more information, see the Cloud Storage C++ API reference documentation.

To authenticate to Cloud Storage, set up Application Default Credentials. For more information, see Set up authentication for a local development environment. 

namespace gcs = ::google::cloud::storage;
using ::google::cloud::StatusOr;
return [](gcs::Client client, std::string const& service_account_email) {
  StatusOr<std::pair<gcs::HmacKeyMetadata, std::string>> key_info =
      client.CreateHmacKey(service_account_email);
  if (!key_info) throw std::move(key_info).status();

  std::cout << "The base64 encoded secret is: " << key_info->second
            << "\nDo not miss that secret, there is no API to recover it."
            << "\nThe HMAC key metadata is: " << key_info->first << "\n";
  return key_info->first.access_id();
}

C#

For more information, see the Cloud Storage C# API reference documentation.

To authenticate to Cloud Storage, set up Application Default Credentials. For more information, see Set up authentication for a local development environment. 


using Google.Apis.Storage.v1.Data;
using Google.Cloud.Storage.V1;
using System;

public class CreateHmacKeySample
{
    public HmacKey CreateHmacKey(
        string projectId = "your-project-id",
        string serviceAccountEmail = "dev@iam.gserviceaccount.com")
    {
        var storage = StorageClient.Create();
        var key = storage.CreateHmacKey(projectId, serviceAccountEmail);

        var secret = key.Secret;
        var metadata = key.Metadata;

        Console.WriteLine($"The Base64 encoded secret is: {secret}");
        Console.WriteLine("Make sure to save that secret, there's no API to recover it.");
        Console.WriteLine("The HMAC key metadata is:");
        Console.WriteLine($"ID: {metadata.Id}");
        Console.WriteLine($"Access ID: {metadata.AccessId}");
        Console.WriteLine($"Project ID: {metadata.ProjectId}");
        Console.WriteLine($"Service Account Email: {metadata.ServiceAccountEmail}");
        Console.WriteLine($"State: {metadata.State}");
        Console.WriteLine($"Time Created: {metadata.TimeCreated}");
        Console.WriteLine($"Time Updated: {metadata.Updated}");
        Console.WriteLine($"ETag: {metadata.ETag}");
        return key;
    }
}

Go

For more information, see the Cloud Storage Go API reference documentation.

To authenticate to Cloud Storage, set up Application Default Credentials. For more information, see Set up authentication for a local development environment. 

import (
	"context"
	"fmt"
	"io"
	"time"

	"cloud.google.com/go/storage"
)

// createHMACKey creates a new HMAC key using the given project and service account.
func createHMACKey(w io.Writer, projectID string, serviceAccountEmail string) (*storage.HMACKey, error) {
	ctx := context.Background()

	// Initialize client.
	client, err := storage.NewClient(ctx)
	if err != nil {
		return nil, fmt.Errorf("storage.NewClient: %w", err)
	}
	defer client.Close() // Closing the client safely cleans up background resources.

	ctx, cancel := context.WithTimeout(ctx, time.Minute)
	defer cancel()
	key, err := client.CreateHMACKey(ctx, projectID, serviceAccountEmail)
	if err != nil {
		return nil, fmt.Errorf("CreateHMACKey: %w", err)
	}

	fmt.Fprintf(w, "%s\n", key)
	fmt.Fprintf(w, "The base64 encoded secret is %s\n", key.Secret)
	fmt.Fprintln(w, "Do not miss that secret, there is no API to recover it.")
	fmt.Fprintln(w, "The HMAC key metadata is")
	fmt.Fprintf(w, "%+v", key)

	return key, nil
}

Java

For more information, see the Cloud Storage Java API reference documentation.

To authenticate to Cloud Storage, set up Application Default Credentials. For more information, see Set up authentication for a local development environment. 


import com.google.cloud.storage.HmacKey;
import com.google.cloud.storage.ServiceAccount;
import com.google.cloud.storage.Storage;
import com.google.cloud.storage.StorageException;
import com.google.cloud.storage.StorageOptions;
import java.util.Date;

public class CreateHmacKey {
  public static void createHmacKey(String serviceAccountEmail, String projectId)
      throws StorageException {

    // The service account email for which the new HMAC key will be created.
    // String serviceAccountEmail = "service-account@iam.gserviceaccount.com";

    // The ID of the project to which the service account belongs.
    // String projectId = "project-id";

    Storage storage = StorageOptions.newBuilder().setProjectId(projectId).build().getService();

    ServiceAccount account = ServiceAccount.of(serviceAccountEmail);
    HmacKey hmacKey =
        storage.createHmacKey(account, Storage.CreateHmacKeyOption.projectId(projectId));

    String secret = hmacKey.getSecretKey();
    HmacKey.HmacKeyMetadata metadata = hmacKey.getMetadata();

    System.out.println("The Base64 encoded secret is: " + secret);
    System.out.println("Do not lose that secret, there is no API to recover it.");
    System.out.println("The HMAC key metadata is:");
    System.out.println("ID: " + metadata.getId());
    System.out.println("Access ID: " + metadata.getAccessId());
    System.out.println("Project ID: " + metadata.getProjectId());
    System.out.println("Service Account Email: " + metadata.getServiceAccount().getEmail());
    System.out.println("State: " + metadata.getState().toString());
    System.out.println("Time Created: " + new Date(metadata.getCreateTime()).toString());
    System.out.println("Time Updated: " + new Date(metadata.getUpdateTime()).toString());
    System.out.println("ETag: " + metadata.getEtag());
  }
}

Node.js

For more information, see the Cloud Storage Node.js API reference documentation.

To authenticate to Cloud Storage, set up Application Default Credentials. For more information, see Set up authentication for a local development environment. 

/**
 * TODO(developer): Uncomment the following lines before running the sample.
 */
// The service account email for which the new HMAC key will be created
// const serviceAccountEmail = 'service-account@iam.gserviceaccount.com';

// The ID of the project to which the service account belongs
// const projectId = 'project-id';

// Imports the Google Cloud client library
const {Storage} = require('@google-cloud/storage');

// Creates a client
const storage = new Storage();

// Create HMAC SA Key
async function createHmacKey() {
  const [hmacKey, secret] = await storage.createHmacKey(serviceAccountEmail, {
    projectId,
  });

  console.log(`The base64 encoded secret is: ${secret}`);
  console.log('Do not miss that secret, there is no API to recover it.');
  console.log('The HMAC key metadata is:');
  for (const [key, value] of Object.entries(hmacKey.metadata)) {
    console.log(`${key}: ${value}`);
  }
}

PHP

For more information, see the Cloud Storage PHP API reference documentation.

To authenticate to Cloud Storage, set up Application Default Credentials. For more information, see Set up authentication for a local development environment. 

use Google\Cloud\Storage\StorageClient;

/**
 * Create a new HMAC key.
 *
 * @param string $projectId The ID of your Google Cloud Platform project.
 *        (e.g. 'my-project-id')
 * @param string $serviceAccountEmail Service account email to associate with the new HMAC key.
 *        (e.g. 'service-account@iam.gserviceaccount.com')
 */
function create_hmac_key(string $projectId, string $serviceAccountEmail): void
{
    $storage = new StorageClient();
    // By default createHmacKey will use the projectId used by StorageClient().
    $hmacKeyCreated = $storage->createHmacKey($serviceAccountEmail, ['projectId' => $projectId]);

    printf('The base64 encoded secret is: %s' . PHP_EOL, $hmacKeyCreated->secret());
    print('Do not miss that secret, there is no API to recover it.' . PHP_EOL);
    printf('HMAC key Metadata: %s' . PHP_EOL, print_r($hmacKeyCreated->hmacKey()->info(), true));
}

Python

For more information, see the Cloud Storage Python API reference documentation.

To authenticate to Cloud Storage, set up Application Default Credentials. For more information, see Set up authentication for a local development environment. 

from google.cloud import storage


def create_key(project_id, service_account_email):
    """
    Create a new HMAC key using the given project and service account.
    """
    # project_id = 'Your Google Cloud project ID'
    # service_account_email = 'Service account used to generate the HMAC key'

    storage_client = storage.Client(project=project_id)

    hmac_key, secret = storage_client.create_hmac_key(
        service_account_email=service_account_email, project_id=project_id
    )

    print(f"The base64 encoded secret is {secret}")
    print("Do not miss that secret, there is no API to recover it.")
    print("The HMAC key metadata is:")
    print(f"Service Account Email: {hmac_key.service_account_email}")
    print(f"Key ID: {hmac_key.id}")
    print(f"Access ID: {hmac_key.access_id}")
    print(f"Project ID: {hmac_key.project}")
    print(f"State: {hmac_key.state}")
    print(f"Created At: {hmac_key.time_created}")
    print(f"Updated At: {hmac_key.updated}")
    print(f"Etag: {hmac_key.etag}")
    return hmac_key

Ruby

For more information, see the Cloud Storage Ruby API reference documentation.

To authenticate to Cloud Storage, set up Application Default Credentials. For more information, see Set up authentication for a local development environment. 

def create_hmac_key service_account_email:
  # The service account email used to generate an HMAC key
  # service_account_email = "service-my-project-number@gs-project-accounts.iam.gserviceaccount.com"

  require "google/cloud/storage"

  storage = Google::Cloud::Storage.new

  # By default Storage#create_hmac_key uses the Storage client project_id
  hmac_key = storage.create_hmac_key service_account_email

  puts "The base64 encoded secret is: #{hmac_key.secret}"
  puts "Do not miss that secret, there is no API to recover it."
  puts "\nThe HMAC key metadata is:"
  puts "Key ID:                #{hmac_key.id}"
  puts "Service Account Email: #{hmac_key.service_account_email}"
  puts "Access ID:             #{hmac_key.access_id}"
  puts "Project ID:            #{hmac_key.project_id}"
  puts "Active:                #{hmac_key.active?}"
  puts "Created At:            #{hmac_key.created_at}"
  puts "Updated At:            #{hmac_key.updated_at}"
  puts "Etag:                  #{hmac_key.etag}"
end

What's next

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