Lock a bucket's retention policy

Provides an example of how to lock a bucket's retention policy.

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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;
[](gcs::Client client, std::string const& bucket_name) {
  StatusOr<gcs::BucketMetadata> original =
      client.GetBucketMetadata(bucket_name);
  if (!original) throw std::move(original).status();

  StatusOr<gcs::BucketMetadata> updated_metadata =
      client.LockBucketRetentionPolicy(bucket_name,
                                       original->metageneration());
  if (!updated_metadata) throw std::move(updated_metadata).status();

  if (!updated_metadata->has_retention_policy()) {
    std::cerr << "The bucket " << updated_metadata->name()
              << " does not have a retention policy, even though the"
              << " operation to set it was successful.\n"
              << "This is unexpected, and may indicate that another"
              << " application has modified the bucket concurrently.\n";
    return;
  }

  std::cout << "Retention policy successfully locked for bucket "
            << updated_metadata->name() << "\nNew retention policy is: "
            << updated_metadata->retention_policy()
            << "\nFull metadata: " << *updated_metadata << "\n";
}

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.Cloud.Storage.V1;
using System;

public class LockRetentionPolicySample
{
    /// <summary>
    /// Locks the retention policy of a bucket. This is a one-way process: once a retention
    /// policy is locked, it cannot be shortened, removed or unlocked, although it can
    /// be increased in duration. The lock persists until the bucket is deleted.
    /// </summary>
    /// <param name="bucketName">The name of the bucket whose retention policy should be locked.</param>
    public bool? LockRetentionPolicy(string bucketName = "your-unique-bucket-name")
    {
        var storage = StorageClient.Create();
        var bucket = storage.GetBucket(bucketName);
        storage.LockBucketRetentionPolicy(bucketName, bucket.Metageneration.Value);
        bucket = storage.GetBucket(bucketName);
        Console.WriteLine($"Retention policy for {bucketName} is now locked");
        Console.WriteLine($"Retention policy effective as of {bucket.RetentionPolicy.EffectiveTime}");

        return bucket.RetentionPolicy.IsLocked;
    }
}

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.

ctx := context.Background()
bucket := c.Bucket(bucketName)

ctx, cancel := context.WithTimeout(ctx, time.Second*50)
defer cancel()
attrs, err := c.Bucket(bucketName).Attrs(ctx)
if err != nil {
	return err
}

conditions := storage.BucketConditions{
	MetagenerationMatch: attrs.MetaGeneration,
}
if err := bucket.If(conditions).LockRetentionPolicy(ctx); err != nil {
	return err
}

lockedAttrs, err := c.Bucket(bucketName).Attrs(ctx)
if err != nil {
	return err
}
log.Printf("Retention policy for %v is now locked\n", bucketName)
log.Printf("Retention policy effective as of %v\n",
	lockedAttrs.RetentionPolicy.EffectiveTime)

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

public class LockRetentionPolicy {
  public static void lockRetentionPolicy(String projectId, String bucketName)
      throws StorageException {
    // The ID of your GCP project
    // String projectId = "your-project-id";

    // The ID of your GCS bucket
    // String bucketName = "your-unique-bucket-name";

    Storage storage = StorageOptions.newBuilder().setProjectId(projectId).build().getService();
    Bucket bucket =
        storage.get(bucketName, Storage.BucketGetOption.fields(Storage.BucketField.METAGENERATION));
    Bucket lockedBucket =
        bucket.lockRetentionPolicy(Storage.BucketTargetOption.metagenerationMatch());

    System.out.println("Retention period for " + bucketName + " is now locked");
    System.out.println(
        "Retention policy effective as of " + new Date(lockedBucket.getRetentionEffectiveTime()));
  }
}

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 ID of your GCS bucket
// const bucketName = 'your-unique-bucket-name';

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

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

async function lockRetentionPolicy() {
  // Gets the current metageneration value for the bucket, required by
  // lock_retention_policy
  const [unlockedMetadata] = await storage.bucket(bucketName).getMetadata();

  // Warning: Once a retention policy is locked, it cannot be unlocked. The
  // retention period can only be increased
  const [lockedMetadata] = await storage
    .bucket(bucketName)
    .lock(unlockedMetadata.metageneration);
  console.log(`Retention policy for ${bucketName} is now locked`);
  console.log(
    `Retention policy effective as of ${lockedMetadata.retentionPolicy.effectiveTime}`
  );

  return lockedMetadata;
}

lockRetentionPolicy().catch(console.error);

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;

/**
 * Locks a bucket's retention policy.
 *
 * @param string $bucketName The name of your Cloud Storage bucket.
 *        (e.g. 'my-bucket')
 */
function lock_retention_policy(string $bucketName): void
{
    $storage = new StorageClient();
    $bucket = $storage->bucket($bucketName);
    $bucket->reload();
    $bucket->lockRetentionPolicy();
    printf('Bucket %s retention policy locked' . PHP_EOL, $bucketName);
}

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 lock_retention_policy(bucket_name):
    """Locks the retention policy on a given bucket"""
    # bucket_name = "my-bucket"

    storage_client = storage.Client()
    # get_bucket gets the current metageneration value for the bucket,
    # required by lock_retention_policy.
    bucket = storage_client.get_bucket(bucket_name)

    # Warning: Once a retention policy is locked it cannot be unlocked
    # and retention period can only be increased.
    bucket.lock_retention_policy()

    print(f"Retention policy for {bucket_name} is now locked")
    print(
        f"Retention policy effective as of {bucket.retention_policy_effective_time}"
    )

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 lock_retention_policy bucket_name:
  # The ID of your GCS bucket
  # bucket_name = "your-unique-bucket-name"

  require "google/cloud/storage"

  storage = Google::Cloud::Storage.new
  bucket  = storage.bucket bucket_name

  # Warning: Once a retention policy is locked it cannot be unlocked
  # and retention period can only be increased.
  # Uses Bucket#metageneration as a precondition.
  bucket.lock_retention_policy!

  puts "Retention policy for #{bucket_name} is now locked."
  puts "Retention policy effective as of #{bucket.retention_effective_at}."
end

What's next

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