Set an event-based hold on an object

An example of how to set an event-based hold on an object.

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

Code sample


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

using Google.Cloud.Storage.V1;
using System;

public class SetEventBasedHoldSample
    public void SetEventBasedHold(
        string bucketName = "your-unique-bucket-name",
        string objectName = "your-object-name")
        var storage = StorageClient.Create();
        var storageObject = storage.GetObject(bucketName, objectName);
        storageObject.EventBasedHold = true;
        Console.WriteLine($"Event-based hold was set for {objectName}.");


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

namespace gcs = ::google::cloud::storage;
using ::google::cloud::StatusOr;
[](gcs::Client client, std::string const& bucket_name,
   std::string const& object_name) {
  StatusOr<gcs::ObjectMetadata> original =
      client.GetObjectMetadata(bucket_name, object_name);
  if (!original) throw std::runtime_error(original.status().message());

  StatusOr<gcs::ObjectMetadata> updated = client.PatchObject(
      bucket_name, object_name,
  if (!updated) throw std::runtime_error(updated.status().message());

  std::cout << "The event hold for object " << updated->name()
            << " in bucket " << updated->bucket() << " is "
            << (updated->event_based_hold() ? "enabled" : "disabled") << "\n";


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

import (


// setEventBasedHold sets EventBasedHold flag of an object to true.
func setEventBasedHold(w io.Writer, bucket, object string) error {
	// bucket := "bucket-name"
	// object := "object-name"
	ctx := context.Background()
	client, err := storage.NewClient(ctx)
	if err != nil {
		return fmt.Errorf("storage.NewClient: %v", err)
	defer client.Close()

	ctx, cancel := context.WithTimeout(ctx, time.Second*10)
	defer cancel()

	o := client.Bucket(bucket).Object(object)

	// Optional: set a generation-match precondition to avoid potential race
	// conditions and data corruptions. The request to upload is aborted if the
	// object's generation number does not match your precondition.
	attrs, err := o.Attrs(ctx)
	if err != nil {
		return fmt.Errorf("object.Attrs: %v", err)
	o = o.If(storage.Conditions{MetagenerationMatch: attrs.Metageneration})

	// Update the object to add the object hold.
	objectAttrsToUpdate := storage.ObjectAttrsToUpdate{
		EventBasedHold: true,
	if _, err := o.Update(ctx, objectAttrsToUpdate); err != nil {
		return fmt.Errorf("Object(%q).Update: %v", object, err)
	fmt.Fprintf(w, "Default event based hold was enabled for %v.\n", object)
	return nil


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


public class SetEventBasedHold {
  public static void setEventBasedHold(String projectId, String bucketName, String objectName)
      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";

    // The ID of your GCS object
    // String objectName = "your-object-name";

    Storage storage = StorageOptions.newBuilder().setProjectId(projectId).build().getService();
    BlobId blobId = BlobId.of(bucketName, objectName);


    System.out.println("Event-based hold was set for " + objectName);


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

 * TODO(developer): Uncomment the following lines before running the sample.
// The ID of your GCS bucket
// const bucketName = 'your-unique-bucket-name';

// The ID of your GCS file
// const fileName = 'your-file-name';

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

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

async function setEventBasedHold() {
  // Set event-based hold
  await storage.bucket(bucketName).file(fileName).setMetadata({
    eventBasedHold: true,
  console.log(`Event-based hold was set for ${fileName}.`);



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

use Google\Cloud\Storage\StorageClient;

 * Sets an event-based hold for an object.
 * @param string $bucketName The name of your Cloud Storage bucket.
 * @param string $objectName The name of your Cloud Storage object.
function set_event_based_hold($bucketName, $objectName)
    // $bucketName = 'my-bucket';
    // $objectName = 'my-object';

    $storage = new StorageClient();
    $bucket = $storage->bucket($bucketName);
    $object = $bucket->object($objectName);
    $object->update(['eventBasedHold' => true]);
    printf('Event-based hold was set for %s' . PHP_EOL, $objectName);


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

from import storage

def set_event_based_hold(bucket_name, blob_name):
    """Sets a event based hold on a given blob"""
    # bucket_name = "my-bucket"
    # blob_name = "my-blob"

    storage_client = storage.Client()
    bucket = storage_client.bucket(bucket_name)
    blob = bucket.blob(blob_name)

    blob.event_based_hold = True

    print(f"Event based hold was set for {blob_name}")


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

def set_event_based_hold bucket_name:, file_name:
  # The ID of your GCS bucket
  # bucket_name = "your-unique-bucket-name"

  # The ID of your GCS object
  # file_name = "your-file-name"

  require "google/cloud/storage"

  storage =
  bucket  = storage.bucket bucket_name, skip_lookup: true
  file    = bucket.file file_name


  puts "Event-based hold was set for #{file_name}."

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