Create and manage access control lists (ACLs)

Overview

This page describes how to control access to buckets and objects using Access Control Lists (ACLs). ACLs are a mechanism you can use to define who has access to your buckets and objects, as well as what level of access they have.

See the ACL overview to learn more about whether you should use ACLs for controlling access to your resources.

Set ACLs

Console

Note: You cannot use the Google Cloud console to set ACLs on buckets; the Console can only be used to set ACLs on individual objects.

1. Go to the Cloud Storage browser in the Google Cloud console.
   Go to the Cloud Storage browser

2. Navigate to the object whose ACL you want to modify.

3. Choose Edit access from the more actions menu () associated with the object.

   You should see a permission dialog that looks like:

   This screenshot shows an ACL with four entries:

   • In the first entry, all owners of a specific project (one whose project number is 867489140601) receive "Owner" access/permission for this object.
   • In the second entry, all editors of a specific project (one whose project number is 867489140601) also receive "Owner" access/permission for this object.
   • In the third entry, all viewers of a specific project (one whose project number is 867489140601) receive "Reader" access/permission for this object.
   • In the fourth entry, the user who uploaded the object receives "Owner" access/permission for the object. Object uploaders are always set as an "Owner" and cannot be removed.

4. Click Add item.

5. Choose the type of Entity to give permission to.

   Entity specifies the type of thing that's getting the permission (for example a user or a group). Refer to Access Control Scopes for a list of supported values for Entity.

6. Enter a value in Name.

   Name identifies a specific user, group, or other entity type. Refer to Access Control Scopes for a list of supported values for Name.

   Together, Entity and Name define who the permission applies to.

7. Choose a value in Access.

   Access defines the permission that you want to set on the object. Refer to Access Control Permissions for a list of supported values for Access.

8. Click Save.

To learn how to get detailed error information about failed Cloud Storage operations in the Google Cloud console, see Troubleshooting.

gsutil

Use gsutil acl to specify ACLs:

• To specify individual grants:

  gsutil acl ch -u USER_EMAIL:PERMISSION gs://BUCKET_NAME

• To specify canned ACLs:

  gsutil acl set CANNED_ACL_NAME gs://BUCKET_NAME

• To specify ACLs in JSON format:

  gsutil acl set JSON_FILE gs://BUCKET_NAME

  where JSON_FILE contains ACLs specified in JSON format.

Client libraries

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.

The following sample adds an ACL to a bucket:

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namespace gcs = ::google::cloud::storage;
using ::google::cloud::StatusOr;
[](gcs::Client client, std::string const& bucket_name,
   std::string const& entity) {
  StatusOr<gcs::BucketAccessControl> patched_acl =
      client.PatchBucketAcl(bucket_name, entity,
                            gcs::BucketAccessControlPatchBuilder().set_role(
                                gcs::BucketAccessControl::ROLE_OWNER()));
  if (!patched_acl) throw std::move(patched_acl).status();
  std::cout << "ACL entry for " << patched_acl->entity() << " in bucket "
            << patched_acl->bucket() << " is now " << *patched_acl << "\n";
}

The following sample adds an ACL to an object:

View on GitHub Feedback

namespace gcs = ::google::cloud::storage;
using ::google::cloud::StatusOr;
[](gcs::Client client, std::string const& bucket_name,
   std::string const& object_name, std::string const& entity) {
  StatusOr<gcs::ObjectAccessControl> patched_acl =
      client.CreateObjectAcl(bucket_name, object_name, entity,
                             gcs::ObjectAccessControl::ROLE_OWNER());

  if (!patched_acl) throw std::move(patched_acl).status();
  std::cout << "ACL entry for " << patched_acl->entity() << " in object "
            << patched_acl->object() << " in bucket " << patched_acl->bucket()
            << " is now " << *patched_acl << "\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.

The following sample adds an ACL to a bucket:

View on GitHub Feedback

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

public class AddBucketOwnerSample
{
    public Bucket AddBucketOwner(
        string bucketName = "your-unique-bucket-name",
        string userEmail = "[e-mail]")
    {
        var storage = StorageClient.Create();
        var bucket = storage.GetBucket(bucketName, new GetBucketOptions { Projection = Projection.Full });

        bucket.Acl ??= new List<BucketAccessControl>();

        bucket.Acl.Add(new BucketAccessControl
        {
            Bucket = bucketName,
            Entity = $"user-{userEmail}",
            Role = "OWNER",
        });
        var updatedBucket = storage.UpdateBucket(bucket);
        Console.WriteLine($"Added user { userEmail } as an owner on bucket { bucketName }.");
        return updatedBucket;
    }
}

The following sample adds an ACL to an object:

View on GitHub Feedback

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

public class AddFileOwnerSample
{
    public Google.Apis.Storage.v1.Data.Object AddFileOwner(
        string bucketName = "your-unique-bucket-name",
        string objectName = "my-file-name",
        string userEmail = "[e-mail]")
    {
        var storage = StorageClient.Create();
        var storageObject = storage.GetObject(bucketName, objectName, new GetObjectOptions
        {
            Projection = Projection.Full
        });

        storageObject.Acl.Add(new ObjectAccessControl
        {
            Bucket = bucketName,
            Entity = $"user-{userEmail}",
            Role = "OWNER",
        });
        var updatedObject = storage.UpdateObject(storageObject);
        Console.WriteLine($"Added user { userEmail} as an owner on file { objectName}.");
        return updatedObject;
    }
}

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.

The following sample adds an ACL to a bucket:

View on GitHub Feedback

import (
	"context"
	"fmt"

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

// addBucketOwner adds ACL to the specified bucket.
func addBucketOwner(bucket string, entity storage.ACLEntity) error {
	// bucket := "bucket-name"
	// entity := storage.AllUsers
	role := storage.RoleOwner

	ctx := context.Background()
	client, err := storage.NewClient(ctx)
	if err != nil {
		return fmt.Errorf("storage.NewClient: %w", err)
	}
	defer client.Close()

	acl := client.Bucket(bucket).ACL()
	if err := acl.Set(ctx, entity, role); err != nil {
		return fmt.Errorf("ACLHandle.Set: %w", err)
	}
	return nil
}

The following sample adds an ACL to an object:

View on GitHub Feedback

import (
	"context"
	"fmt"

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

// addFileOwner adds ACL to the specified object.
func addFileOwner(bucket, object string, entity storage.ACLEntity) error {
	// bucket := "bucket-name"
	// object := "object-name"
	// entity := storage.AllUsers
	role := storage.RoleOwner

	ctx := context.Background()
	client, err := storage.NewClient(ctx)
	if err != nil {
		return fmt.Errorf("storage.NewClient: %w", err)
	}
	defer client.Close()

	acl := client.Bucket(bucket).Object(object).ACL()
	if err := acl.Set(ctx, entity, role); err != nil {
		return fmt.Errorf("ACLHandle.Set: %w", err)
	}
	return 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.

The following sample adds an ACL to a bucket:

View on GitHub Feedback

import com.google.cloud.storage.Acl;
import com.google.cloud.storage.Acl.Role;
import com.google.cloud.storage.Acl.User;
import com.google.cloud.storage.Bucket;
import com.google.cloud.storage.Storage;
import com.google.cloud.storage.StorageOptions;

public class AddBucketOwner {

  public static void addBucketOwner(String projectId, String bucketName, String userEmail) {
    // The ID of your GCP project
    // String projectId = "your-project-id";

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

    // Email of the user you wish to add as an owner
    // String userEmail = "[e-mail]"

    Storage storage = StorageOptions.newBuilder().setProjectId(projectId).build().getService();
    Bucket bucket = storage.get(bucketName);
    Acl newOwner = Acl.of(new User(userEmail), Role.OWNER);

    bucket.createAcl(newOwner);
    System.out.println("Added user " + userEmail + " as an owner on " + bucketName);
  }
}

The following sample adds an ACL to an object:

View on GitHub Feedback

import com.google.cloud.storage.Acl;
import com.google.cloud.storage.Acl.Role;
import com.google.cloud.storage.Acl.User;
import com.google.cloud.storage.Blob;
import com.google.cloud.storage.BlobId;
import com.google.cloud.storage.Storage;
import com.google.cloud.storage.StorageOptions;

public class AddFileOwner {

  public static void addFileOwner(
      String projectId, String bucketName, String userEmail, String blobName) {
    // The ID of your GCP project
    // String projectId = "your-project-id";

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

    // Email of the user you wish to add as a file owner
    // String userEmail = "[e-mail]"

    // The name of the blob/file that you wish to modify permissions on
    // String blobName = "your-blob-name";

    Storage storage = StorageOptions.newBuilder().setProjectId(projectId).build().getService();
    Blob blob = storage.get(BlobId.of(bucketName, blobName));
    Acl newOwner = Acl.of(new User(userEmail), Role.OWNER);

    blob.createAcl(newOwner);
    System.out.println(
        "Added user "
            + userEmail
            + " as an owner on file "
            + blobName
            + " in bucket "
            + bucketName);
  }
}

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.

The following sample adds an ACL to a bucket:

View on GitHub Feedback

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

// The email address of the user to add
// const userEmail = 'user-email-to-add';

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

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

async function addBucketOwner() {
  // Makes the user an owner of the bucket. You can use addAllUsers(),
  // addDomain(), addProject(), addGroup(), and addAllAuthenticatedUsers()
  // to grant access to different types of entities. You can also use "readers"
  // and "writers" to grant different roles.
  await storage.bucket(bucketName).acl.owners.addUser(userEmail);

  console.log(`Added user ${userEmail} as an owner on bucket ${bucketName}.`);
}

addBucketOwner().catch(console.error);

The following sample adds an ACL to an object:

View on GitHub Feedback

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

// The name of the file to access
// const fileName = 'file.txt';

// The email address of the user to add
// const userEmail = 'user-email-to-add';

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

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

async function addFileOwner() {
  await storage
    .bucket(bucketName)
    .file(fileName)
    .acl.owners.addUser(userEmail);

  console.log(`Added user ${userEmail} as an owner on file ${fileName}.`);
}

addFileOwner().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.

The following sample adds an ACL to a bucket:

View on GitHub Feedback

use Google\Cloud\Storage\StorageClient;

/**
 * Add an entity and role to a bucket's ACL.
 *
 * @param string $bucketName The name of your Cloud Storage bucket.
 *        (e.g. 'my-bucket')
 * @param string $entity The entity for which to update access controls.
 *        (e.g. '[e-mail]')
 * @param string $role The permissions to add for the specified entity.
 *        (e.g. 'OWNER')
 */
function add_bucket_acl(string $bucketName, string $entity, string $role): void
{
    $storage = new StorageClient();
    $bucket = $storage->bucket($bucketName);
    $acl = $bucket->acl();
    $acl->add($entity, $role);
    printf('Added %s (%s) to gs://%s ACL' . PHP_EOL, $entity, $role, $bucketName);
}

The following sample adds an ACL to an object:

View on GitHub Feedback

use Google\Cloud\Storage\StorageClient;

/**
 * Add an entity and role to an object's ACL.
 *
 * @param string $bucketName The name of your Cloud Storage bucket.
 *        (e.g. 'my-bucket')
 * @param string $objectName The name of your Cloud Storage object.
 *        (e.g. 'my-object')
 * @param string $entity The entity for which to update access controls.
 *        (e.g. '[e-mail]')
 * @param string $role The permissions to add for the specified entity.
 *        (e.g. 'OWNER')
 */
function add_object_acl(string $bucketName, string $objectName, string $entity, string $role): void
{
    $storage = new StorageClient();
    $bucket = $storage->bucket($bucketName);
    $object = $bucket->object($objectName);
    $acl = $object->acl();
    $acl->add($entity, $role);
    printf('Added %s (%s) to gs://%s/%s ACL' . PHP_EOL, $entity, $role, $bucketName, $objectName);
}

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.

The following sample adds an ACL to a bucket:

View on GitHub Feedback

from google.cloud import storage


def add_bucket_owner(bucket_name, user_email):
    """Adds a user as an owner on the given bucket."""
    # bucket_name = "your-bucket-name"
    # user_email = "[e-mail]"

    storage_client = storage.Client()

    bucket = storage_client.bucket(bucket_name)

    # Reload fetches the current ACL from Cloud Storage.
    bucket.acl.reload()

    # You can also use `group()`, `domain()`, `all_authenticated()` and `all()`
    # to grant access to different types of entities.
    # You can also use `grant_read()` or `grant_write()` to grant different
    # roles.
    bucket.acl.user(user_email).grant_owner()
    bucket.acl.save()

    print(
        f"Added user {user_email} as an owner on bucket {bucket_name}."
    )

The following sample adds an ACL to an object:

View on GitHub Feedback

from google.cloud import storage


def add_blob_owner(bucket_name, blob_name, user_email):
    """Adds a user as an owner on the given blob."""
    # bucket_name = "your-bucket-name"
    # blob_name = "your-object-name"
    # user_email = "[e-mail]"

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

    # Reload fetches the current ACL from Cloud Storage.
    blob.acl.reload()

    # You can also use `group`, `domain`, `all_authenticated` and `all` to
    # grant access to different types of entities. You can also use
    # `grant_read` or `grant_write` to grant different roles.
    blob.acl.user(user_email).grant_owner()
    blob.acl.save()

    print(
        "Added user {} as an owner on blob {} in bucket {}.".format(
            user_email, blob_name, bucket_name
        )
    )

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.

The following sample adds an ACL to a bucket:

View on GitHub Feedback

# The ID of your GCS bucket
# bucket_name = "your-unique-bucket-name"
# email       = "Google Cloud Storage ACL Entity email"

require "google/cloud/storage"

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

bucket.acl.add_owner email

puts "Added OWNER permission for #{email} to #{bucket_name}"

The following sample adds an ACL to an object:

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# The ID of your GCS bucket
# bucket_name = "your-unique-bucket-name"
# file_name   = "Name of a file in the Storage bucket"
# email       = "Google Cloud Storage ACL Entity email"

require "google/cloud/storage"

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

file.acl.add_owner email

puts "Added OWNER permission for #{email} to #{file_name}"

JSON API

When creating a bucket, you can specify the acl[] property in an insert request. For an existing bucket, specify the acl[] property in a patch or update request.

When creating an object, you can specify the acl[] property in the request body or the predefinedAcl query parameter in an insert request. For an existing object, specify the acl[] property or the predefinedAcl query parameter in a patch or update request.

For definitions of the bucket and object ACL properties, see the BucketAccessControls and ObjectAccessControls resources, respectively.

The following example shows different bucket ACL entries.

"acl": [
{
"kind": "storage#bucketAccessControl",
"id": "example-bucket/project-owners-123412341234",
"selfLink": "https://www.googleapis.com/storage/v1/b/example-bucket/acl/project-owners-123412341234",
"bucket": "example-bucket",
"entity": "project-owners-123412341234",
"role": "OWNER",
"projectTeam": {
       "projectNumber": "123412341234",
       "team": "owners"
},
"etag": "CDk="
},
{
"kind": "storage#bucketAccessControl",
"id": "example-bucket/project-editors-123412341234",
"selfLink": "https://www.googleapis.com/storage/v1/b/example-bucket/acl/project-editors-123412341234",
"bucket": "example-bucket",
"entity": "project-editors-123412341234",
"role": "OWNER",
"projectTeam": {
     "projectNumber": "123412341234",
     "team": "editors"
},
"etag": "CDk="
},
{
"kind": "storage#bucketAccessControl",
"id": "example-bucket/project-viewers-123412341234",
"selfLink": "https://www.googleapis.com/storage/v1/b/example-bucket/acl/project-viewers-123412341234",
"bucket": "example-bucket",
"entity": "project-viewers-123412341234",
"role": "READER",
"projectTeam": {
     "projectNumber": "123412341234",
     "team": "viewers"
},
"etag": "CDk="
},
{
"kind": "storage#bucketAccessControl",
"id": "example-bucket/[e-mail]",
"selfLink": "https://www.googleapis.com/storage/v1/b/example-bucket/acl/[e-mail]",
"bucket": "example-bucket",
"entity": "[e-mail]",
"role": "READER",
"email": "[e-mail]",
"etag": "CDk="
},
{
"kind": "storage#bucketAccessControl",
"id": "example-bucket/[e-mail]",
"selfLink": "https://www.googleapis.com/storage/v1/b/example-bucket/acl/[e-mail]",
"bucket": "example-bucket",
"entity": "[e-mail]",
"role": "READER",
"email": "[e-mail]",
"etag": "CDk="
},
{
"kind": "storage#bucketAccessControl",
"id": "example-bucket/allUsers",
"selfLink": "https://www.googleapis.com/storage/v1/b/example-bucket/acl/allUsers",
"bucket": "example-bucket",
"entity": "allUsers",
"role": "READER",
"etag": "CDk="
},
{
"kind": "storage#bucketAccessControl",
"id": "example-bucket/allAuthenticatedUsers",
"selfLink": "https://www.googleapis.com/storage/v1/b/example-bucket/acl/allAuthenticatedUsers",
"bucket": "example-bucket",
"entity": "allAuthenticatedUsers",
"role": "READER",
"etag": "CDk="
}
]

XML API

In the XML API, you work with ACLs in XML format. You must attach an XML document to the body of requests to change bucket and object ACLs. An XML document is returned when you get bucket and object ACLs. The XML document contains the individual bucket or object ACL entries.

• After creating a bucket with a PUT Bucket request, use a second PUT Bucket request with the ?acl parameter to change the bucket ACL.

• After uploading an object with a PUT Object request, change the ACL with another PUT request using the ?acl parameter or the x-googl-acl request header.

Use the following ACL syntax for the XML API.

Element	Description
AccessControlList	Container for Entries and Owner elements.
Owner	Container for DisplayName and ID elements. This element is not required for objects since an object is always owned by the user who uploaded it. This element is used when you are using Amazon S3 ACL syntax in a migration scenario. Amazon Simple Storage Service^™ and Amazon S3^™ are trademarks of Amazon.com, Inc. or its affiliates in the United States and/or other countries.
ID	Google Cloud Storage ID of the bucket owner.
DisplayName	Not currently implemented. The value is always an empty string.
Entries	Container for zero or more Entry elements.
Entry	Container for Scope and Permission elements. An Entry must contain only one Scope and one Permission element.
Scope	Container for an ID, EmailAddress, or Domain element that defines the ACL scope. This element must have a type attribute that contains one of the following values: UserByID, UserByEmail, GroupByID, GroupByEmail, GroupByDomain, AllUsers, or AllAuthenticatedUsers.
ID	An identifier for the grantee when the permission entry is specified by ID.
EmailAddress	The email identifier for the grantee when the permission entry is specified by email.
Domain	The domain identifier for the grantee when the permission entry is specified by domain.
Name	Optional element that can be specified or that can be automatically added if the scope is UserByEmail or GroupByEmail.
Permission	The permission granted READ, WRITE, or FULL_CONTROL.

When working with ACLs using the XML API:

• You can only use the XML format described above.

• You cannot set duplicate scopes.

  You can have many entries in your ACL XML, but you cannot have entries with duplicate scopes. For example, you cannot have two entries with the same scope element of [e-mail].

The following example shows different bucket ACL entries:

<?xml version="1.0" encoding="UTF-8"?>
<AccessControlList>
<Owner>
    <ID>00b4903a9721...</ID>
</Owner>
<Entries>
    <Entry>
      <Scope type="GroupById">
        <ID>00b4903a9722...</ID>
      </Scope>
      <Permission>FULL_CONTROL</Permission>
    </Entry>
    <Entry>
      <Scope type="GroupById">
        <ID>00b4903a9723...</ID>
      </Scope>
      <Permission>FULL_CONTROL</Permission>
    </Entry>
    <Entry>
      <Scope type="GroupById">
        <ID>00b4903a9724...</ID>
      </Scope>
      <Permission>READ</Permission>
    </Entry>
    <Entry>
      <Scope type="GroupByDomain">
        <Domain>example.com</Domain>
      </Scope>
      <Permission>READ</Permission>
    </Entry>
    <Entry>
      <Scope type="GroupByEmail">
        <EmailAddress>[e-mail]</EmailAddress>
      </Scope>
      <Permission>READ</Permission>
    </Entry>
    <Entry>
      <Scope type="UserByEmail">
        <EmailAddress>[e-mail]</EmailAddress>
        <Name>jane</Name>
      </Scope>
      <Permission>READ</Permission>
    </Entry>
    <Entry>
      <Scope type="AllUsers"/>
      <Permission>READ</Permission>
    </Entry>
    <Entry>
      <Scope type="AllAuthenticatedUsers"/>
      <Permission>READ</Permission>
    </Entry>
</Entries>
</AccessControlList>

Set the Name element in ACL XML

When you retrieve an ACL from a bucket or object, you might notice an additional <Name> element appended to some of your entries. For example, you might see an entry that looks like the following:

<Entry>
    <Scope type="UserByEmail">
      <EmailAddress>[e-mail]</EmailAddress>
      <Name>Jane</Name>
    </Scope>
    <Permission>FULL_CONTROL</Permission>
</Entry>

These optional <Name> elements are populated in two circumstances:

1. When the bucket or object's ACLs include <Name> as an element.

   When you set ACLs, you can choose to include the <Name> element with your ACL entries. You can provide any value in the <Name> element, and Cloud Storage remembers these values until the ACL is removed or replaced. This approach can be useful if you are using identifiers that aren't easily identifiable, like Google Cloud Storage IDs.

2. When a UserByEmail or GroupByEmail scope contains a public Google profile.

   If you use either of these scopes but do not provide a <Name> element, Cloud Storage checks if the user or Google Group associated with the email address has a public Google profile with a public name. If so, Cloud Storage automatically populates the <Name> element with the public name.

Apply a predefined ACL

Rather than specifying the entire ACL one entry at a time as shown above, you can use a predefined ACL, which will automatically apply a number of entries customized to a specific scenario. You can apply a predefined ACL to either a bucket or an object by using gsutil, the JSON API, or the XML API.

On new objects

To apply a predefined ACL to an object during object upload:

Console

You cannot apply a predefined ACL using the Google Cloud console. Use gsutil instead.

gsutil

Use the -a option with the gsutil cp command to apply the predefined ACL:

gsutil cp -a PREDEFINED_ACL OBJECT gs://BUCKET_NAME

For example, to apply the predefined ACL bucket-owner-read while uploading an object paris.jpg to a bucket example-travel-maps:

gsutil cp -a bucket-owner-read paris.jpg gs://example-travel-maps

JSON API

Use the predefinedAcl query string parameter in an insert request to apply the prefined ACL.

For example, to apply the predefined ACL bucketOwnerRead while uploading an object paris.jpg to a bucket example-travel-maps:

curl -X POST --data-binary @paris.jpg -H "Content-Type: image/jpeg" 

     -H "Authorization: Bearer ya29.AHES6ZRVmB7fkLtd1XTmq6mo0S1wqZZi3-Lh_s-6Uw7p8vtgSwg"  

     "https://storage.googleapis.com/upload/storage/v1/b/example-travel-maps/o?name=paris.jpg&predefinedAcl=bucketOwnerRead"

The request looks like the following example:

POST /upload/storage/v1/b/example-travel-maps/o?name=paris.jpg&amppredefinedAcl=bucketOwnerRead HTTP/1.1
Host: www.googleapis.com
Content-Type: image/jpeg
Authorization: Bearer ya29.AHES6ZRVmB7fkLtd1XTmq6mo0S1wqZZi3-Lh_s-6Uw7p8vtgSwg
Content-Length: 12345
Date: Fri, 10 Oct 2014 00:02:38 GMT

XML API

Use the x-goog-acl header in a Put Object request to apply the predefined ACL.

For example, to apply the predefined ACL bucket-owner-read while uploading an object paris.jpg to a bucket example-travel-maps:

curl -X PUT --upload-file paris.jpg -H "x-goog-acl: bucket-owner-read" 

     -H "Authorization: Bearer ya29.AHES6ZRVmB7fkLtd1XTmq6mo0S1wqZZi3-Lh_s-6Uw7p8vtgSwg"  

     https://storage.googleapis.com/example-travel-maps/paris.jpg

The request looks like the following example:

PUT /paris.jpg HTTP/1.1
Host: example-travel-maps.storage.googleapis.com
Date: Thu, 09 Oct 2014 23:06:08 GMT
Content-Length: 12345
Content-Type: image/jpg
x-goog-acl: bucket-owner-read
Authorization: Bearer ya29.AHES6ZRVmB7fkLtd1XTmq6mo0S1wqZZi3-Lh_s-6Uw7p8vtgSwg
 
12345 bytes in entity body

On existing buckets or objects

You can also apply a predefined ACL to an existing bucket or object, which is useful if you want to change from one predefined ACL to another, or you want to update custom ACLs to a predefined ACL.

Console

You cannot apply a predefined ACL using the Google Cloud console. Use gsutil instead.

gsutil

Use the gsutil acl set command to apply the predefined ACL:

gsutil acl set PREDEFINED_ACL gs://BUCKET_NAME/OBJECT_NAME

For example, to apply the predefined ACL private to the object paris.jpg in the bucket example-travel-maps:

gsutil acl set private gs://example-travel-maps/paris.jpg

JSON API

Use the predefinedAcl query string parameter, and specify an empty acl property in a patch request to apply the prefined ACL.

For example, to apply the predefined ACL private to the object paris.jpg in the bucket example-travel-maps:

curl -X PATCH --data '{"acl": []}'  -H "Content-Type: application/json" 

     -H "Authorization: Bearer ya29.AHES6ZRVmB7fkLtd1XTmq6mo0S1wqZZi3-Lh_s-6Uw7p8vtgSwg"  

     https://storage.googleapis.com/storage/v1/b/example-travel-maps/o/paris.jpg?predefinedAcl=private

The request looks like the following example:

PATCH /storage/v1/b/example-travel-maps/o/paris.jpg?predefinedAcl=private HTTP/1.1
Host: www.googleapis.com
Content-Type: application/json
Authorization: Bearer ya29.AHES6ZRVmB7fkLtd1XTmq6mo0S1wqZZi3-Lh_s-6Uw7p8vtgSwg
Content-Length: 11
Date: Fri, 10 Oct 2014 18:57:59 GMT

XML API

Use the x-goog-acl header with the acl query string parameter in a Put Object request, but do not include an XML document in your request.

For example, to apply the predefined ACL private to the object paris.jpg in the bucket example-travel-maps:

curl -X PUT -H "Content-Length: 0" 

    -H "Authorization: Bearer ya29.AHES6ZRVmB7fkLtd1XTmq6mo0S1wqZZi3-Lh_s-6Uw7p8vtgSwg" 

    -H "x-goog-acl: private" https://storage.googleapis.com/example-travel-maps/paris.jpg?acl

The request looks like the following example:

PUT /paris.jpg?acl HTTP/1.1
Host: example-travel-maps.storage.googleapis.com
Date: Thu, 09 Oct 2014 23:14:59 GMT
Content-Length: 0
x-goog-acl: private
Authorization: Bearer ya29.AHES6ZRVmB7fkLtd1XTmq6mo0S1wqZZi3-Lh_s-6Uw7p8vtgSwg
 
empty entity body

Set default object ACLs

To avoid setting ACLs every time you create a new object, you can set a default object ACL on a bucket. After you do this, every new object that is added to that bucket that does not explicitly have an ACL applied to it will have the default applied to it. For example, you might want to specify that only a certain group of users have access to most objects in a particular bucket. You can change the default object ACL, and then add objects to the bucket. These added objects have the default object ACL you specified automatically applied to them; however, you can give specific objects different ACLs, in which case those objects do not have the default ACL applied to them.

Important: If you change the default object ACL for a bucket, the change may take time to propagate, and new objects created in the bucket may still get the old default object ACL for a short period of time (see Consistency). In order to make sure that new objects created in the bucket get the updated default object ACL, you should wait at least 30 seconds between changing the default object ACL and creating new objects.

To view and change the default object ACL for a bucket:

Console

You cannot set default object ACLs using the Google Cloud console. Use gsutil instead.

gsutil

1. Use gsutil defacl to retrieve the default object ACL:

   gsutil defacl get gs://BUCKET_NAME

2. Use gsutil defacl ch or gsutil defacl set to modify the default object ACL.

   For example, the following command adds [e-mail] to the default object ACL for a bucket example-travel-maps:

   gsutil defacl ch -u [e-mail]:READER gs://example-travel-maps

   You can also specify the default object ACL from a file. For more information, see the help for gsutil defacl.

Client libraries

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.

The following sample adds a default object ACL to a bucket:

View on GitHub Feedback

namespace gcs = ::google::cloud::storage;
using ::google::cloud::StatusOr;
[](gcs::Client client, std::string const& bucket_name,
   std::string const& entity, std::string const& role) {
  StatusOr<gcs::ObjectAccessControl> default_object_acl =
      client.CreateDefaultObjectAcl(bucket_name, entity, role);
  if (!default_object_acl) throw std::move(default_object_acl).status();

  std::cout << "Role " << default_object_acl->role()
            << " will be granted default to " << default_object_acl->entity()
            << " on any new object created on bucket "
            << default_object_acl->bucket() << "\n"
            << "Full attributes: " << *default_object_acl << "\n";
}

The following sample deletes a default object ACL from a bucket:

View on GitHub Feedback

namespace gcs = ::google::cloud::storage;
[](gcs::Client client, std::string const& bucket_name,
   std::string const& entity) {
  google::cloud::Status status =
      client.DeleteDefaultObjectAcl(bucket_name, entity);

  if (!status.ok()) throw std::runtime_error(status.message());
  std::cout << "Deleted ACL entry for " << entity << " in bucket "
            << bucket_name << "\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.

The following sample prints the default object ACL for a bucket:

View on GitHub Feedback

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

public class PrintBucketDefaultAclSample
{
    public IEnumerable<ObjectAccessControl> PrintBucketDefaultAcl(string bucketName = "your-unique-bucket-name")
    {
        var storage = StorageClient.Create();
        var bucket = storage.GetBucket(bucketName, new GetBucketOptions { Projection = Projection.Full });

        foreach (var acl in bucket.DefaultObjectAcl)
        {
            Console.WriteLine($"{acl.Role}:{acl.Entity}");
        }

        return bucket.DefaultObjectAcl;
    }
}

The following sample adds a default object ACL to a bucket:

View on GitHub Feedback

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

public class AddBucketDefaultOwnerSample
{
    public Bucket AddBucketDefaultOwner(
        string bucketName = "your-unique-bucket-name",
        string userEmail = "[e-mail]")
    {
        var storage = StorageClient.Create();
        var bucket = storage.GetBucket(bucketName, new GetBucketOptions { Projection = Projection.Full });

        bucket.DefaultObjectAcl.Add(new ObjectAccessControl
        {
            Bucket = bucketName,
            Entity = $"user-{userEmail}",
            Role = "OWNER",
        });
        var updatedBucket = storage.UpdateBucket(bucket);
        Console.WriteLine($"Added user {userEmail} as a default owner on bucket {bucketName}.");
        return updatedBucket;
    }
}

The following sample deletes a default object ACL from a bucket:

View on GitHub Feedback

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

public class RemoveBucketDefaultOwnerSample
{
    public void RemoveBucketDefaultOwner(
        string bucketName = "your-unique-bucket-name",
        string userEmail = "[e-mail]")
    {
        var storage = StorageClient.Create();
        var bucket = storage.GetBucket(bucketName, new GetBucketOptions { Projection = Projection.Full });
        if (bucket.DefaultObjectAcl == null)
        {
            Console.WriteLine("No default owner to remove");
        }
        else
        {
            bucket.DefaultObjectAcl = bucket.DefaultObjectAcl.Where(acl => !(acl.Entity == $"user-{userEmail}" && acl.Role == "OWNER")).ToList();
            var updatedBucket = storage.UpdateBucket(bucket);
            Console.WriteLine($"Removed user {userEmail} from bucket {bucketName}.");
        }
    }
}

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.

The following sample adds a default object ACL to a bucket:

View on GitHub Feedback

import (
	"context"
	"fmt"

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

// addBucketDefaultOwner adds default ACL to the specified bucket.
func addBucketDefaultOwner(bucket string, entity storage.ACLEntity) error {
	// bucket := "bucket-name"
	// entity := storage.AllUsers
	role := storage.RoleOwner

	ctx := context.Background()
	client, err := storage.NewClient(ctx)
	if err != nil {
		return fmt.Errorf("storage.NewClient: %w", err)
	}
	defer client.Close()

	acl := client.Bucket(bucket).DefaultObjectACL()
	if err := acl.Set(ctx, entity, role); err != nil {
		return fmt.Errorf("ACLHandle.Set: %w", err)
	}
	return nil
}

The following sample deletes a default object ACL from a bucket:

View on GitHub Feedback

import (
	"context"
	"fmt"

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

// deleteDefaultBucketACL removes default ACL from a bucket.
func removeBucketDefaultOwner(bucket string, entity storage.ACLEntity) error {
	// bucket := "bucket-name"
	// entity := storage.AllUsers
	ctx := context.Background()
	client, err := storage.NewClient(ctx)
	if err != nil {
		return fmt.Errorf("storage.NewClient: %w", err)
	}
	defer client.Close()

	acl := client.Bucket(bucket).DefaultObjectACL()
	if err := acl.Delete(ctx, entity); err != nil {
		return fmt.Errorf("ACLHandle.Delete: %w", err)
	}
	return 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.

The following sample adds a default object ACL to a bucket:

View on GitHub Feedback

import com.google.cloud.storage.Acl;
import com.google.cloud.storage.Acl.Role;
import com.google.cloud.storage.Acl.User;
import com.google.cloud.storage.Bucket;
import com.google.cloud.storage.Storage;
import com.google.cloud.storage.StorageOptions;

public class AddBucketDefaultOwner {

  public static void addBucketDefaultOwner(String bucketName, String userEmail) {

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

    // The email of the user you wish to add as a default owner
    // String userEmail = "[e-mail]"

    Storage storage = StorageOptions.newBuilder().build().getService();
    Bucket bucket = storage.get(bucketName);
    Acl newDefaultOwner = Acl.of(new User(userEmail), Role.OWNER);

    bucket.createDefaultAcl(newDefaultOwner);
    System.out.println("Added user " + userEmail + " as an owner on " + bucketName);
  }
}

The following sample deletes a default object ACL from a bucket:

View on GitHub Feedback

import com.google.cloud.storage.Acl.User;
import com.google.cloud.storage.Bucket;
import com.google.cloud.storage.Storage;
import com.google.cloud.storage.StorageOptions;

public class RemoveBucketDefaultOwner {

  public static void removeBucketDefaultOwner(String bucketName, String userEmail) {

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

    // The email of the user you wish to remove as a default owner
    // String userEmail = "[e-mail]"

    Storage storage = StorageOptions.newBuilder().build().getService();
    Bucket bucket = storage.get(bucketName);
    User userToRemove = new User(userEmail);

    boolean success = bucket.deleteDefaultAcl(userToRemove);
    if (success) {
      System.out.println("Removed user " + userEmail + " as an owner on " + bucketName);
    } else {
      System.out.println("User " + userEmail + " was not found");
    }
  }
}

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.

The following sample adds a default object ACL to a bucket:

View on GitHub Feedback

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

// The email address of the user to add
// const userEmail = 'user-email-to-add';

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

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

async function addBucketDefaultOwner() {
  // Makes the user an owner in the default ACL of the bucket. You can use
  // addAllUsers(), addDomain(), addProject(), addGroup(), and
  // addAllAuthenticatedUsers() to grant access to different types of entities.
  // You can also use "readers" and "writers" to grant different roles.
  await storage.bucket(bucketName).acl.default.owners.addUser(userEmail);

  console.log(`Added user ${userEmail} as an owner on bucket ${bucketName}.`);
}

addBucketDefaultOwner().catch(console.error);

The following sample deletes a default object ACL from a bucket:

View on GitHub Feedback

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

// The email address of the user to remove
// const userEmail = 'user-email-to-remove';

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

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

async function removeBucketDefaultOwner() {
  // Removes the user from the access control list of the bucket. You can use
  // deleteAllUsers(), deleteDomain(), deleteProject(), deleteGroup(), and
  // deleteAllAuthenticatedUsers() to remove access for different types of entities.
  await storage.bucket(bucketName).acl.default.owners.deleteUser(userEmail);

  console.log(`Removed user ${userEmail} from bucket ${bucketName}.`);
}

removeBucketDefaultOwner().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.

The following sample adds a default object ACL to a bucket:

View on GitHub Feedback

use Google\Cloud\Storage\StorageClient;

/**
 * Add an entity and role to a bucket's default ACL.
 *
 * @param string $bucketName The name of your Cloud Storage bucket.
 *        (e.g. 'my-bucket')
 * @param string $entity The entity for which to update access controls.
 *        (e.g. '[e-mail]')
 * @param string $role The permissions to add for the specified entity.
 *        (e.g. 'OWNER')
 */
function add_bucket_default_acl(string $bucketName, string $entity, string $role): void
{
    $storage = new StorageClient();
    $bucket = $storage->bucket($bucketName);
    $acl = $bucket->defaultAcl();
    $acl->add($entity, $role);
    printf('Added %s (%s) to gs://%s default ACL' . PHP_EOL, $entity, $role, $bucketName);
}

The following sample deletes a default object ACL from a bucket:

View on GitHub Feedback

use Google\Cloud\Storage\StorageClient;

/**
 * Delete an entity from a bucket's default ACL.
 *
 * @param string $bucketName The name of your Cloud Storage bucket.
 *        (e.g. 'my-bucket')
 * @param string $entity The entity for which to update access controls.
 *        (e.g. '[e-mail]')
 */
function delete_bucket_default_acl(string $bucketName, string $entity): void
{
    $storage = new StorageClient();
    $bucket = $storage->bucket($bucketName);
    $acl = $bucket->defaultAcl();
    $acl->delete($entity);
    printf('Deleted %s from gs://%s default ACL' . PHP_EOL, $entity, $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.

The following sample adds a default object ACL to a bucket:

View on GitHub Feedback

from google.cloud import storage


def add_bucket_default_owner(bucket_name, user_email):
    """Adds a user as an owner in the given bucket's default object access
    control list."""
    # bucket_name = "your-bucket-name"
    # user_email = "[e-mail]"

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

    # Reload fetches the current ACL from Cloud Storage.
    bucket.acl.reload()

    # You can also use `group`, `domain`, `all_authenticated` and `all` to
    # grant access to different types of entities. You can also use
    # `grant_read` or `grant_write` to grant different roles.
    bucket.default_object_acl.user(user_email).grant_owner()
    bucket.default_object_acl.save()

    print(
        "Added user {} as an owner in the default acl on bucket {}.".format(
            user_email, bucket_name
        )
    )

The following sample deletes a default object ACL from a bucket:

View on GitHub Feedback

from google.cloud import storage


def remove_bucket_default_owner(bucket_name, user_email):
    """Removes a user from the access control list of the given bucket's
    default object access control list."""
    # bucket_name = "your-bucket-name"
    # user_email = "[e-mail]"

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

    # Reload fetches the current ACL from Cloud Storage.
    bucket.acl.reload()

    # You can also use `group`, `domain`, `all_authenticated` and `all` to
    # remove access for different types of entities.
    bucket.default_object_acl.user(user_email).revoke_read()
    bucket.default_object_acl.user(user_email).revoke_write()
    bucket.default_object_acl.user(user_email).revoke_owner()
    bucket.default_object_acl.save()

    print(
        f"Removed user {user_email} from the default acl of bucket {bucket_name}."
    )

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.

The following sample adds a default object ACL to a bucket:

View on GitHub Feedback

# The ID of your GCS bucket
# bucket_name = "your-unique-bucket-name"
# email       = "Google Cloud Storage ACL Entity email"

require "google/cloud/storage"

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

bucket.default_acl.add_owner email

puts "Added default OWNER permission for #{email} to #{bucket_name}"

The following sample deletes a default object ACL from a bucket:

View on GitHub Feedback

# The ID of your GCS bucket
# bucket_name = "your-unique-bucket-name"
# email       = "Google Cloud Storage ACL Entity email"

require "google/cloud/storage"

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

bucket.default_acl.delete email

puts "Removed default ACL permissions for #{email} from #{bucket_name}"

JSON API

1. Retrieve the default object ACL with a GET request. For example:

   curl -X GET -H "Authorization: Bearer OAUTH2_TOKEN" 
   
   https://storage.googleapis.com/storage/v1/b/BUCKET_NAME?projection=full

2. Use a patch request to replace the default object ACL. For example, the following request replaces the default object ACL with the ACL specified in defacls.json for a bucket example-travel-maps:

   curl -X PATCH --data @defacls.json -H "Content-Type: application/json" -H "Authorization: Bearer OAUTH2_TOKEN" 
   
   https://storage.googleapis.com/storage/v1/b/example-travel-maps

   An example of defacls.json:

   {
   "defaultObjectAcl": [
   {
   "email": "[e-mail]",
   "entity": "[e-mail]",
   "role": "READER"
   }
   ]
   }
   

XML API

1. Retrieve the default object ACL with a GET request scoped to your bucket and the ?defaultObjectAcl parameter. For example:

   curl -X GET -H "Authorization: Bearer OAUTH2_TOKEN" 
   
   https://storage.googleapis.com/BUCKET_NAME?defaultObjectAcl

2. Use a PUT request scoped to your bucket with the ?defaultObjectAcl parameter to replace the default object ACL with the ACL specified in acls.xml. For example:

   curl -X PUT --data-binary @acls.xml -H "Authorization: Bearer OAUTH2_TOKEN" 
   
   http://storage.googleapis.com/BUCKET_NAME?defaultObjectAcl

   An example of acls.xml:

   <AccessControlList>
   <Entries>
   <Entry>
   <Permission>FULL_CONTROL</Permission>
   <Scope type="GroupByEmail">
   <EmailAddress>[e-mail]</EmailAddress>
   </Scope>
   </Entry>
   </Entries>
   </AccessControlList>

The syntax of ACLs is discussed in Setting ACLs. You can also specify a predefined ACL as the default object ACL.

To set the default object ACL for a bucket to a predefined ACL:

Console

You cannot set default object ACLs using the Google Cloud console. Use gsutil instead.

gsutil

Use the gsutil defacl command with the name of the predefined ACL.

For example, to set the default object ACL to project-private for the bucket example-travel-maps:

gsutil defacl set project-private gs://example-travel-maps

JSON API

Use a PUT request and the predefinedAcl parameter.

For example:

curl -X PUT -H "Content-Length: 0" -H "Authorization: Bearer OAUTH2_TOKEN" 

https://storage.googleapis.com/storage/v1/b/BUCKET_NAME?predefinedAcl=private

XML API

Use a PUT request scoped to your bucket with the ?defaultObjectAcl parameter and the x-goog-acl header.

For example:

curl -X PUT -H "x-goog-acl: project-private" -H "Content-Length: 0" -H "Authorization: Bearer OAUTH2_TOKEN" 

http://storage.googleapis.com/BUCKET_NAME?defaultObjectAcl

The default object ACLs for a newly created bucket:

Shown below are the default object ACLs for a newly created bucket. Compare these to the default object ACLs of your bucket to see if your bucket's default object ACLs have been modified.

Console

You cannot work with default object ACLs using the Google Cloud console. Use gsutil instead.

gsutil

In the example below, the project ID is "123412341234"; your project ID will be different.

[
{
"entity": "project-owners-123412341234",
"projectTeam": {
  "projectNumber": "123412341234",
  "team": "owners"
},
"role": "OWNER"
},
{
"entity": "project-editors-123412341234",
"projectTeam": {
  "projectNumber": "123412341234",
  "team": "editors"
},
"role": "OWNER"
},
{
"entity": "project-viewers-123412341234",
"projectTeam": {
  "projectNumber": "123412341234",
  "team": "viewers"
},
"role": "READER"
}
]

JSON API

In the example below, the project ID is "123412341234"; your project ID will be different.

defaultObjectAcl": [
{
"kind": "storage#objectAccessControl",
"entity": "project-owners-123412341234",
"role": "OWNER",
"projectTeam": {
"projectNumber": "123412341234",
"team": "owners"
}
},
{
"kind": "storage#objectAccessControl",
"entity": "project-editors-123412341234",
"role": "OWNER",
"projectTeam": {
"projectNumber": "123412341234",
"team": "editors"
}
},
{
"kind": "storage#objectAccessControl",
"entity": "project-viewers-123412341234",
"role": "READER",
"projectTeam": {
"projectNumber": "123412341234",
"team": "viewers"
}
}
]

XML API

In the example below, the project role IDs start with "00b4903a97..."; your project IDs will be different.

<?xml version='1.0' encoding='UTF-8'?>
<AccessControlList>
<Entries>
<Entry>
  <Scope type='GroupById'>
    <ID>00b4903a9721...</ID>
  </Scope>
  <Permission>FULL_CONTROL</Permission>
</Entry>
<Entry>
  <Scope type='GroupById'>
    <ID>00b4903a9722...</ID>
  </Scope>
  <Permission>FULL_CONTROL</Permission>
</Entry>
<Entry>
  <Scope type='GroupById'>
    <ID>00b4903a9723...</ID>
  </Scope>
  <Permission>READ</Permission>
</Entry>
</Entries>
</AccessControlList>

Note that the default object ACL for a newly created bucket is equivalent to the predefined projectPrivate ACL.

Retrieving ACLs

To get the ACL of an existing bucket or object:

Console

Note: You cannot use the Google Cloud console to get ACLs on buckets; the Console can only be used to get ACLs on individual objects.

1. Go to the Cloud Storage browser in the Google Cloud console.
   Go to the Cloud Storage browser

2. Navigate to the object whose ACL you want to view.

3. Choose Edit access from the drop down menu for the object.

   You should see a permission dialog with the object's permissions.

To learn how to get detailed error information about failed Cloud Storage operations in the Google Cloud console, see Troubleshooting.

gsutil

Use the gsutil acl get to return an object's ACL.

For example, to return the ACL of the object paris.jpg in the bucket example-travel-maps:

gsutil acl get gs://example-travel-maps/paris.jpg

Example response:

[
{
    "entity": "project-owners-123412341234",
    "projectTeam": {
      "projectNumber": "123412341234",
      "team": "owners"
    },
    "role": "OWNER"
},
{
    "entity": "project-editors-123412341234",
    "projectTeam": {
      "projectNumber": "123412341234",
      "team": "editors"
    },
    "role": "OWNER"
},
{
    "entity": "project-viewers-123412341234",
    "projectTeam": {
      "projectNumber": "123412341234",
      "team": "viewers"
    },
    "role": "READER"
},
{
    "email": "[e-mail]",
    "entity": "[e-mail]",
    "role": "READER"
},
{
    "email": "[e-mail]",
    "entity": "[e-mail]",
    "role": "READER"
},
{
    "entity": "allUsers",
    "role": "READER"
},
{
    "entity": "allAuthenticatedUsers",
    "role": "READER"
}
]

To return a bucket's ACL:

gsutil acl get gs://BUCKET_NAME

When gsutil returns ACLs for buckets and objects with gsutil acl get, they are in the same JSON format that you can use to set ACLs. ACLs in JSON format use the JSON API property names, such as entity and role.

See the JSON API syntax for more information about how to interpret the output or run gsutil help acls.

Client libraries

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.

The following sample gets a bucket ACL:

View on GitHub Feedback

namespace gcs = ::google::cloud::storage;
using ::google::cloud::StatusOr;
[](gcs::Client client, std::string const& bucket_name) {
  StatusOr<std::vector<gcs::BucketAccessControl>> items =
      client.ListBucketAcl(bucket_name);

  if (!items) throw std::move(items).status();
  std::cout << "ACLs for bucket=" << bucket_name << "\n";
  for (gcs::BucketAccessControl const& acl : *items) {
    std::cout << acl.role() << ":" << acl.entity() << "\n";
  }
}

The following sample gets an object ACL:

View on GitHub Feedback

namespace gcs = ::google::cloud::storage;
using ::google::cloud::StatusOr;
[](gcs::Client client, std::string const& bucket_name,
   std::string const& object_name) {
  StatusOr<std::vector<gcs::ObjectAccessControl>> items =
      client.ListObjectAcl(bucket_name, object_name);

  if (!items) throw std::move(items).status();
  std::cout << "ACLs for object=" << object_name << " in bucket "
            << bucket_name << "\n";
  for (gcs::ObjectAccessControl const& acl : *items) {
    std::cout << acl.role() << ":" << acl.entity() << "\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.

The following sample gets a bucket ACL:

View on GitHub Feedback

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

public class PrintBucketAclSample
{
    public IEnumerable<BucketAccessControl> PrintBucketAcl(string bucketName = "your-unique-bucket-name")
    {
        var storage = StorageClient.Create();
        var bucket = storage.GetBucket(bucketName, new GetBucketOptions { Projection = Projection.Full });

        foreach (var acl in bucket.Acl)
        {
            Console.WriteLine($"{acl.Role}:{acl.Entity}");
        }

        return bucket.Acl;
    }
}

The following sample gets an object ACL:

View on GitHub Feedback

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

public class PrintFileAclSample
{
    public IEnumerable<ObjectAccessControl> PrintObjectAcl(
        string bucketName = "your-unique-bucket-name",
        string objectName = "your-object-name")
    {
        var storage = StorageClient.Create();
        var storageObject = storage.GetObject(bucketName, objectName, new GetObjectOptions
        {
            Projection = Projection.Full
        });

        foreach (var acl in storageObject.Acl)
        {
            Console.WriteLine($"{acl.Role}:{acl.Entity}");
        }

        return storageObject.Acl;
    }
}

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.

The following sample gets a bucket ACL:

View on GitHub Feedback

import (
	"context"
	"fmt"
	"io"

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

// printBucketACL lists bucket ACL.
func printBucketACL(w io.Writer, bucket string) error {
	// bucket := "bucket-name"
	ctx := context.Background()
	client, err := storage.NewClient(ctx)
	if err != nil {
		return fmt.Errorf("storage.NewClient: %w", err)
	}
	defer client.Close()

	rules, err := client.Bucket(bucket).ACL().List(ctx)
	if err != nil {
		return fmt.Errorf("ACLHandle.List: %w", err)
	}
	for _, rule := range rules {
		fmt.Fprintf(w, "ACL rule: %v\n", rule)
	}
	return nil
}

The following sample gets an object ACL:

View on GitHub Feedback

import (
	"context"
	"fmt"
	"io"

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

// printFileACL lists ACL of the specified object.
func printFileACL(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: %w", err)
	}
	defer client.Close()

	rules, err := client.Bucket(bucket).Object(object).ACL().List(ctx)
	if err != nil {
		return fmt.Errorf("ACLHandle.List: %w", err)
	}
	for _, rule := range rules {
		fmt.Fprintf(w, "ACL rule: %v\n", rule)
	}
	return 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.

The following sample gets a bucket ACL:

View on GitHub Feedback

import com.google.cloud.storage.Acl;
import com.google.cloud.storage.Bucket;
import com.google.cloud.storage.Storage;
import com.google.cloud.storage.StorageOptions;
import java.util.List;

public class PrintBucketAcl {

  public static void printBucketAcl(String projectId, String bucketName) {
    // 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);
    List<Acl> bucketAcls = bucket.getAcl();

    for (Acl acl : bucketAcls) {

      // This will give you the role.
      // See https://cloud.google.com/storage/docs/access-control/lists#permissions
      String role = acl.getRole().name();

      // This will give you the Entity type (i.e. User, Group, Project etc.)
      // See https://cloud.google.com/storage/docs/access-control/lists#scopes
      String entityType = acl.getEntity().getType().name();

      System.out.printf("%s: %s \n", role, entityType);
    }
  }
}

The following sample gets an object ACL:

View on GitHub Feedback

import com.google.cloud.storage.Acl;
import com.google.cloud.storage.Blob;
import com.google.cloud.storage.BlobId;
import com.google.cloud.storage.Storage;
import com.google.cloud.storage.StorageOptions;
import java.util.List;

public class PrintFileAcl {

  public static void printFileAcl(String bucketName, String blobName) {

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

    // The name of the blob/file that you wish to view Acls of
    // String blobName = "your-blob-name";

    Storage storage = StorageOptions.newBuilder().build().getService();
    Blob blob = storage.get(BlobId.of(bucketName, blobName));
    List<Acl> blobAcls = blob.getAcl();

    for (Acl acl : blobAcls) {

      // This will give you the role.
      // See https://cloud.google.com/storage/docs/access-control/lists#permissions
      String role = acl.getRole().name();

      // This will give you the Entity type (i.e. User, Group, Project etc.)
      // See https://cloud.google.com/storage/docs/access-control/lists#scopes
      String entityType = acl.getEntity().getType().name();

      System.out.printf("%s: %s %n", role, entityType);
    }
  }
}

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.

The following sample gets a bucket ACL:

View on GitHub Feedback

/**
 * 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 printBucketAcl() {
  // Gets the ACL for the bucket
  const [acls] = await storage.bucket(bucketName).acl.get();

  acls.forEach(acl => {
    console.log(`${acl.role}: ${acl.entity}`);
  });
}
printBucketAcl().catch(console.error);

The following sample gets an object ACL:

View on GitHub Feedback

/**
 * 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 printFileAcl() {
  // Gets the ACL for the file
  const [acls] = await storage.bucket(bucketName).file(fileName).acl.get();

  acls.forEach(acl => {
    console.log(`${acl.role}: ${acl.entity}`);
  });
}

printFileAcl().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.

The following sample gets a bucket ACL:

View on GitHub Feedback

use Google\Cloud\Storage\StorageClient;

/**
 * Print all entities and roles for a bucket's ACL.
 *
 * @param string $bucketName The name of your Cloud Storage bucket.
 *        (e.g. 'my-bucket')
 */
function get_bucket_acl(string $bucketName): void
{
    $storage = new StorageClient();
    $bucket = $storage->bucket($bucketName);
    $acl = $bucket->acl();
    foreach ($acl->get() as $item) {
        printf('%s: %s' . PHP_EOL, $item['entity'], $item['role']);
    }
}

The following sample gets an object ACL:

View on GitHub Feedback

use Google\Cloud\Storage\StorageClient;

/**
 * Print all entities and roles for an object's ACL.
 *
 * @param string $bucketName The name of your Cloud Storage bucket.
 *        (e.g. 'my-bucket')
 * @param string $objectName The name of your Cloud Storage object.
 *        (e.g. 'my-object')
 */
function get_object_acl(string $bucketName, string $objectName): void
{
    $storage = new StorageClient();
    $bucket = $storage->bucket($bucketName);
    $object = $bucket->object($objectName);
    $acl = $object->acl();
    foreach ($acl->get() as $item) {
        printf('%s: %s' . PHP_EOL, $item['entity'], $item['role']);
    }
}

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.

The following sample gets a bucket ACL:

View on GitHub Feedback

from google.cloud import storage


def print_bucket_acl(bucket_name):
    """Prints out a bucket's access control list."""

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

    for entry in bucket.acl:
        print(f"{entry['role']}: {entry['entity']}")

The following sample gets an object ACL:

View on GitHub Feedback

from google.cloud import storage


def print_blob_acl(bucket_name, blob_name):
    """Prints out a blob's access control list."""

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

    for entry in blob.acl:
        print(f"{entry['role']}: {entry['entity']}")

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.

The following sample gets a bucket ACL:

View on GitHub Feedback

# 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

puts "ACL for #{bucket_name}:"

bucket.acl.owners.each do |owner|
  puts "OWNER #{owner}"
end

bucket.acl.writers.each do |writer|
  puts "WRITER #{writer}"
end

bucket.acl.readers.each do |reader|
  puts "READER #{reader}"
end

The following sample gets an object ACL:

View on GitHub Feedback

# The ID of your GCS bucket
# bucket_name = "your-unique-bucket-name"
# file_name   = "Name of a file in the Storage bucket"
# email       = "Google Cloud Storage ACL Entity email"

require "google/cloud/storage"

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

puts "ACL for #{file_name} in #{bucket_name}:"

file.acl.owners.each do |owner|
  puts "OWNER #{owner}"
end

file.acl.readers.each do |reader|
  puts "READER #{reader}"
end

JSON API

1. Make sure that you have OWNER permission on the bucket or object.

2. Retrieve the bucket or object's ACL with a GET request.

   The object ACL is returned in JSON format, attached to the body of the response.

For example, to return the ACL for the object paris.jpg in the bucket example-travel-maps:

curl -X GET -H "Authorization: Bearer ya29.AHES6ZRVmB7fkLtd1XTmq6mo0S1wqZZi3-Lh_s-6Uw7p8vtgSwg" 

 https://storage.googleapis.com/storage/v1/b/example-travel-maps/o/paris.jpg?projection=full

You should see a response that looks like:

{
"kind": "storage#object",
"id": "example-travel-maps/paris.jpg/1412805837131000",
"selfLink": "https://www.googleapis.com/storage/v1/b/example-travel-maps/o/paris.jpg",
"name": "paris.jpg",
"bucket": "example-travel-maps",
...
"acl": [
{
...
"entity": "project-owners-867489160491",
"role": "OWNER",
"projectTeam": {
    "projectNumber": "867489160491",
    "team": "owners"
},
...
},
{
...
"entity": "[e-mail]",
"role": "OWNER",
"email": "[e-mail]",
...
},
{
...
"entity": "[e-mail]",
"role": "READER",
"email": "[e-mail]",
...
}
],
"owner": {
"entity": "[e-mail]"
},
...
}

You can also use the objectAccessControls resource GET method to return individual entries in an object's ACL.

XML API

1. Make sure that you have FULL_CONTROL permission on the bucket or object.

2. Retrieve the bucket or object's ACL by using the acl query string parameter in a GET Object request.

The ACLs are described in XML, attached to the body of the response.

For example, to return the ACL for the object paris.jpg in the bucket example-travel-maps:

curl -X GET -H "Authorization: Bearer ya29.AHES6ZRVmB7fkLtd1XTmq6mo0S1wqZZi3-Lh_s-6Uw7p8vtgSwg" 

 https://storage.googleapis.com/example-travel-maps/paris.jpg?acl

You should see a response that looks like:

<?xml version="1.0" encoding="UTF-8"?>
<AccessControlList>
<Owner>
<ID>84fac329bceSAMPLE777d5d22b8SAMPLE77d85ac2SAMPLE2dfcf7c4adf34da46</ID>
<Name>Owner Name</Name>
</Owner>
<Entries>
<Entry>
  <Scope type="UserById">
    <ID>84fac329bceSAMPLE777d5d22b8SAMPLE77d85ac2SAMPLE2dfcf7c4adf34da46</ID>
    <Name>Name</Name>
  </Scope>
  <Permission>FULL_CONTROL</Permission>
</Entry>
<Entry>
  <Scope type="UserByEmail">
    <EmailAddress>[e-mail]</EmailAddress>
    <Name>Jane</Name>
  </Scope>
  <Permission>FULL_CONTROL</Permission>
</Entry>
<Entry>
  <Scope type="GroupByEmail">
    <EmailAddress>[e-mail]</EmailAddress>
  </Scope>
  <Permission>READ</Permission>
</Entry>
</Entries>
</AccessControlList>

You can also use the JSON GET method of the ObjectAccessControls resource to return a specific ACL entry.

Caution: ACLs work independently from IAM permissions. You can use these two access control methods to customize your permissions. However, if you grant access to your buckets and objects using IAM permissions, such permissions do not appear in the ACLs for individual buckets or objects (except for legacyBucket roles).

Changing ACLs

To change the ACL of an existing object or bucket:

Console

Note: You cannot use the Google Cloud console to change ACLs on buckets; the Console can only be used to change ACLs on individual objects.

1. Go to the Cloud Storage browser in the Google Cloud console.
   Go to the Cloud Storage browser

2. Navigate to the object whose ACL you want to change.

3. Choose Edit access from the drop down menu for the object.

   You should see a permission dialog with the object's permissions.

The following example shows how to grant the [e-mail] user OWNER permission and the members of the gs-announce group READER permission on the object paris.jpg:

To learn how to get detailed error information about failed Cloud Storage operations in the Google Cloud console, see Troubleshooting.

gsutil

1. Define the ACLs in a file.

2. Pass the ACLs file to gsutil acl set, and specify the object to set the ACLs on.

For example, to apply the ACLs from the file acls.txt on an object named paris.jpg in the bucket example-travel-maps:

gsutil acl set acl.txt gs://example-travel-maps/paris.jpg

The contents of acl.txt are shown below. These ACLs grant the owners of project 867489160491 along with the user [e-mail] OWNER permission for the object paris.jpg, and they grant the members of the gs-announce group READER permission for this object:

[
{
"entity": "project-owners-867489160491",
"role": "OWNER",
"projectTeam": {
    "projectNumber": "867489160491",
    "team": "owners"
},
},
{
"entity": "[e-mail]",
"email": "[e-mail]",
"role": "OWNER"
},
{
"entity": "[e-mail]",
"email": "[e-mail]",
"role": "READER"
}
]

You can also set the same ACL for this object with individual grants. For example, to grant the [e-mail] user READER access use:

gsutil acl ch -u [e-mail]:READ gs://example-travel-maps/paris.jpg

.

Client libraries

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.

The following sample removes an ACL from a bucket:

View on GitHub Feedback

namespace gcs = ::google::cloud::storage;
using ::google::cloud::StatusOr;
[](gcs::Client client, std::string const& bucket_name,
   std::string const& entity) {
  StatusOr<gcs::BucketMetadata> original_metadata =
      client.GetBucketMetadata(bucket_name, gcs::Projection::Full());
  if (!original_metadata) throw std::move(original_metadata).status();

  std::vector<gcs::BucketAccessControl> original_acl =
      original_metadata->acl();
  auto it = std::find_if(original_acl.begin(), original_acl.end(),
                         [entity](gcs::BucketAccessControl const& entry) {
                           return entry.entity() == entity &&
                                  entry.role() ==
                                      gcs::BucketAccessControl::ROLE_OWNER();
                         });

  if (it == original_acl.end()) {
    std::cout << "Could not find entity " << entity
              << " with role OWNER in bucket " << bucket_name << "\n";
    return;
  }

  gcs::BucketAccessControl owner = *it;
  google::cloud::Status status =
      client.DeleteBucketAcl(bucket_name, owner.entity());

  if (!status.ok()) throw std::runtime_error(status.message());
  std::cout << "Deleted ACL entry for " << owner.entity() << " in bucket "
            << bucket_name << "\n";
}

The following sample removes an ACL from an object:

View on GitHub Feedback

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

  std::vector<gcs::ObjectAccessControl> original_acl =
      original_metadata->acl();
  auto it = std::find_if(original_acl.begin(), original_acl.end(),
                         [entity](gcs::ObjectAccessControl const& entry) {
                           return entry.entity() == entity &&
                                  entry.role() ==
                                      gcs::ObjectAccessControl::ROLE_OWNER();
                         });

  if (it == original_acl.end()) {
    std::cout << "Could not find entity " << entity << " for file "
              << object_name << " with role OWNER in bucket " << bucket_name
              << "\n";
    return;
  }

  gcs::ObjectAccessControl owner = *it;
  google::cloud::Status status =
      client.DeleteObjectAcl(bucket_name, object_name, owner.entity());

  if (!status.ok()) throw std::runtime_error(status.message());
  std::cout << "Deleted ACL entry for " << owner.entity() << " for file "
            << object_name << " in bucket " << bucket_name << "\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.

The following sample removes an ACL from a bucket:

View on GitHub Feedback

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

public class RemoveBucketOwnerSample
{
    public void RemoveBucketOwner(
        string bucketName = "your-unique-bucket-name",
        string userEmail = "[e-mail]")
    {
        var storage = StorageClient.Create();
        var bucket = storage.GetBucket(bucketName, new GetBucketOptions { Projection = Projection.Full });
        if (bucket.Acl == null)
        {
            Console.WriteLine("No owner to remove");
        }
        else
        {
            bucket.Acl = bucket.Acl.Where(acl => !(acl.Entity == $"user-{userEmail}" && acl.Role == "OWNER")).ToList();
            var updatedBucket = storage.UpdateBucket(bucket);
            Console.WriteLine($"Removed user {userEmail} from bucket {bucketName}.");
        }
    }
}

The following sample removes an ACL from an object:

View on GitHub Feedback

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

public class RemoveFileOwnerSample
{
    public void RemoveFileOwner(
        string bucketName = "your-unique-bucket-name",
        string objectName = "your-object-name",
        string userEmail = "[e-mail]")
    {
        var storage = StorageClient.Create();
        var storageObject = storage.GetObject(bucketName, objectName, new GetObjectOptions { Projection = Projection.Full });
        if (storageObject.Acl == null)
        {
            Console.WriteLine("No owner to remove");
        }
        else
        {
            storageObject.Acl = storageObject.Acl.Where((acl) => !(acl.Entity == $"user-{userEmail}" && acl.Role == "OWNER")).ToList();
            var updatedObject = storage.UpdateObject(storageObject);
            Console.WriteLine($"Removed user {userEmail} from file {objectName}.");
        }
    }
}

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.

The following sample removes an ACL from a bucket:

View on GitHub Feedback

import (
	"context"
	"fmt"

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

// removeBucketOwner removes ACL from a bucket.
func removeBucketOwner(bucket string, entity storage.ACLEntity) error {
	// bucket := "bucket-name"
	// entity := storage.AllUsers
	ctx := context.Background()
	client, err := storage.NewClient(ctx)
	if err != nil {
		return fmt.Errorf("storage.NewClient: %w", err)
	}
	defer client.Close()

	acl := client.Bucket(bucket).ACL()
	if err := acl.Delete(ctx, entity); err != nil {
		return fmt.Errorf("ACLHandle.Delete: %w", err)
	}
	return nil
}

The following sample removes an ACL from an object:

View on GitHub Feedback

import (
	"context"
	"fmt"

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

// removeFileOwner removes default ACL from the given object.
func removeFileOwner(bucket, object string, entity storage.ACLEntity) error {
	// bucket := "bucket-name"
	// object := "object-name"
	// entity := storage.AllUsers
	ctx := context.Background()
	client, err := storage.NewClient(ctx)
	if err != nil {
		return fmt.Errorf("storage.NewClient: %w", err)
	}
	defer client.Close()

	acl := client.Bucket(bucket).Object(object).ACL()
	if err := acl.Delete(ctx, entity); err != nil {
		return fmt.Errorf("ACLHandle.Delete: %w", err)
	}
	return 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.

The following sample removes an ACL from a bucket:

View on GitHub Feedback

import com.google.cloud.storage.Acl.User;
import com.google.cloud.storage.Bucket;
import com.google.cloud.storage.Storage;
import com.google.cloud.storage.StorageOptions;

public class RemoveBucketOwner {

  public static void removeBucketOwner(String projectId, String bucketName, String userEmail) {

    // The ID of your GCP project
    // String projectId = "your-project-id";

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

    // Email of the user you wish to remove as an owner
    // String userEmail = "[e-mail]"

    Storage storage = StorageOptions.newBuilder().setProjectId(projectId).build().getService();
    Bucket bucket = storage.get(bucketName);
    User ownerToRemove = new User(userEmail);

    boolean success = bucket.deleteAcl(ownerToRemove);
    if (success) {
      System.out.println("Removed user " + userEmail + " as an owner on " + bucketName);
    } else {
      System.out.println("User " + userEmail + " was not found");
    }
  }
}

The following sample removes an ACL from an object:

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import com.google.cloud.storage.Acl.User;
import com.google.cloud.storage.Blob;
import com.google.cloud.storage.BlobId;
import com.google.cloud.storage.Storage;
import com.google.cloud.storage.StorageOptions;

public class RemoveFileOwner {

  public static void removeFileOwner(
      String projectId, String bucketName, String userEmail, String blobName) {
    // The ID of your GCP project
    // String projectId = "your-project-id";

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

    // Email of the user you wish to remove as a file owner
    // String userEmail = "[e-mail]"

    // The name of the blob/file that you wish to modify permissions on
    // String blobName = "your-blob-name";

    Storage storage = StorageOptions.newBuilder().setProjectId(projectId).build().getService();
    Blob blob = storage.get(BlobId.of(bucketName, blobName));
    User ownerToRemove = new User(userEmail);

    boolean success = blob.deleteAcl(ownerToRemove);
    if (success) {
      System.out.println(
          "Removed user "
              + userEmail
              + " as an owner on file "
              + blobName
              + " in bucket "
              + bucketName);
    } else {
      System.out.println("User " + userEmail + " was not found");
    }
  }
}

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.

The following sample removes an ACL from a bucket::

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

// The email address of the user to remove
// const userEmail = 'user-email-to-remove';

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

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

async function removeBucketOwner() {
  // Removes the user from the access control list of the bucket. You can use
  // deleteAllUsers(), deleteDomain(), deleteProject(), deleteGroup(), and
  // deleteAllAuthenticatedUsers() to remove access for different types of entities.
  await storage.bucket(bucketName).acl.owners.deleteUser(userEmail);

  console.log(`Removed user ${userEmail} from bucket ${bucketName}.`);
}

removeBucketOwner().catch(console.error);

The following sample removes an ACL from an object:

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/**
 * 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';

// The email address of the user to remove
// const userEmail = 'user-email-to-remove';

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

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

async function removeFileOwner() {
  // Removes the user from the access control list of the file. You can use
  // deleteAllUsers(), deleteDomain(), deleteProject(), deleteGroup(), and
  // deleteAllAuthenticatedUsers() to remove access for different types of entities.
  await storage
    .bucket(bucketName)
    .file(fileName)
    .acl.owners.deleteUser(userEmail);

  console.log(`Removed user ${userEmail} from file ${fileName}.`);
}

removeFileOwner().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.

The following sample removes an ACL from a bucket:

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use Google\Cloud\Storage\StorageClient;

/**
 * Delete an entity from a bucket's default ACL.
 *
 * @param string $bucketName The name of your Cloud Storage bucket.
 *        (e.g. 'my-bucket')
 * @param string $entity The entity for which to update access controls.
 *        (e.g. '[e-mail]')
 */
function delete_bucket_acl(string $bucketName, string $entity): void
{
    $storage = new StorageClient();
    $bucket = $storage->bucket($bucketName);
    $acl = $bucket->acl();
    $acl->delete($entity);
    printf('Deleted %s from gs://%s ACL' . PHP_EOL, $entity, $bucketName);
}

The following sample removes an ACL from an object:

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use Google\Cloud\Storage\StorageClient;

/**
 * Delete an entity from an object's ACL.
 *
 * @param string $bucketName The name of your Cloud Storage bucket.
 *        (e.g. 'my-bucket')
 * @param string $objectName The name of your Cloud Storage object.
 *        (e.g. 'my-object')
 * @param string $entity The entity for which to update access controls.
 *        (e.g. '[e-mail]')
 */
function delete_object_acl(string $bucketName, string $objectName, string $entity): void
{
    $storage = new StorageClient();
    $bucket = $storage->bucket($bucketName);
    $object = $bucket->object($objectName);
    $acl = $object->acl();
    $acl->delete($entity);
    printf('Deleted %s from gs://%s/%s ACL' . PHP_EOL, $entity, $bucketName, $objectName);
}

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.

The following sample removes an ACL from a bucket:

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from google.cloud import storage


def remove_bucket_owner(bucket_name, user_email):
    """Removes a user from the access control list of the given bucket."""
    # bucket_name = "your-bucket-name"
    # user_email = "[e-mail]"

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

    # Reload fetches the current ACL from Cloud Storage.
    bucket.acl.reload()

    # You can also use `group`, `domain`, `all_authenticated` and `all` to
    # remove access for different types of entities.
    bucket.acl.user(user_email).revoke_read()
    bucket.acl.user(user_email).revoke_write()
    bucket.acl.user(user_email).revoke_owner()
    bucket.acl.save()

    print(f"Removed user {user_email} from bucket {bucket_name}.")

The following sample removes an ACL from an object:

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from google.cloud import storage


def remove_blob_owner(bucket_name, blob_name, user_email):
    """Removes a user from the access control list of the given blob in the
    given bucket."""
    # bucket_name = "your-bucket-name"
    # blob_name = "your-object-name"
    # user_email = "[e-mail]"

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

    # You can also use `group`, `domain`, `all_authenticated` and `all` to
    # remove access for different types of entities.
    blob.acl.user(user_email).revoke_read()
    blob.acl.user(user_email).revoke_write()
    blob.acl.user(user_email).revoke_owner()
    blob.acl.save()

    print(
        f"Removed user {user_email} from blob {blob_name} in bucket {bucket_name}."
    )

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.

The following sample removes an ACL from a bucket:

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# project_id  = "Your Google Cloud project ID"
# The ID of your GCS bucket
# bucket_name = "your-unique-bucket-name"
# email       = "Google Cloud Storage ACL Entity email"

require "google/cloud/storage"

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

bucket.acl.delete email

puts "Removed ACL permissions for #{email} from #{bucket_name}"

The following sample removes an ACL from an object:

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# The ID of your GCS bucket
# bucket_name = "your-unique-bucket-name"
# file_name   = "Name of a file in the Storage bucket"
# email       = "Google Cloud Storage ACL Entity email"

require "google/cloud/storage"

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

file.acl.delete email

puts "Removed ACL permissions for #{email} from #{file_name}"

JSON API

1. Define the ACLs in a JSON file.

2. Send a patch request with the JSON file, and specify the object to set the ACLs on.

For example, the following cURL command applies a JSON payload from the document acls.json to an object named paris.jpg in the bucket example-travel-maps:

curl -X PATCH --data @acls.json -H "Content-Type: application/json" 

 -H "Authorization: Bearer ya29.AHES6ZRVmB7fkLtd1XTmq6mo0S1wqZZi3-Lh_s-6Uw7p8vtgSwg" 

 https://storage.googleapis.com/storage/v1/b/example-travel-maps/o/paris.jpg

If the ACL grants the owners of project 867489160491 and the user [e-mail] OWNER permission, along with granting the members of the gs-announce group READER permission, then the request looks like the following example:

PATCH /storage/v1/b/example-travel-maps/o/paris.jpg HTTP/1.1
Host: www.googleapis.com
Content-Type: application/json
Authorization: Bearer ya29.AHES6ZRVmB7fkLtd1XTmq6mo0S1wqZZi3-Lh_s-6Uw7p8vtgSwg
Content-Length: 597
Date: Wed, 08 Oct 2014 22:37:58 GMT
{
"acl": [
{
"entity": "project-owners-867489160491",
"role": "OWNER",
"projectTeam": {
    "projectNumber": "867489160491",
    "team": "owners"
},
{
"entity": "[e-mail]",
"role": "OWNER",
"email": "[e-mail]"
},
{
"entity": "[e-mail]",
"role": "READER",
"email": "[e-mail]"
}
]
}

XML API

1. Define the ACLs in an XML document.

2. Send a PUT Object request using the acl query string parameter and the corresponding XML document.

The following cURL command applies an XML payload from the document acls.xml to an object named paris.jpg in the bucket example-travel-maps:

curl -X PUT --data-binary @acls.xml 

 -H "Authorization: Bearer ya29.AHES6ZRVmB7fkLtd1XTmq6mo0S1wqZZi3-Lh_s-6Uw7p8vtgSwg" 

 https://storage.googleapis.com/example-travel-maps/paris.jpg?acl

If the ACL grants the [e-mail] user FULL_CONTROL permission and the members of the gs-announce group READ permission, then the request looks like the following example:

PUT /paris.jpg?acl HTTP/1.1
Host: example-travel-maps.storage.googleapis.com
Date: Sat, 20 Feb 2010 08:31:08 GMT
Content-Length: 589
Content-Type=application/xml
Authorization: Bearer ya29.AHES6ZRVmB7fkLtd1XTmq6mo0S1wqZZi3-Lh_s-6Uw7p8vtgSwg
 
<?xml version='1.0' encoding='utf-8'?>
<AccessControlList>
<Owner>
<ID>84fac329bceSAMPLE777d5d22b8SAMPLE77d85ac2SAMPLE2dfcf7c4adf34da46</ID>
</Owner>
<Entries>
<Entry>
<Permission>FULL_CONTROL</Permission>
<Scope type="UserById">
  <ID>84fac329bceSAMPLE777d5d22b8SAMPLE77d85ac2SAMPLE2dfcf7c4adf34da46</ID>
</Scope>
</Entry>
<Entry>
<Scope type="UserByEmail">
  <EmailAddress>[e-mail]</EmailAddress>
  <Name>Jane</Name>
</Scope>
<Permission>FULL_CONTROL</Permission>
</Entry>
<Entry>
<Scope type="GroupByEmail">
  <EmailAddress>[e-mail]</EmailAddress>
</Scope>
<Permission>READ</Permission>
</Entry>
</Entries>
</AccessControlList>

What's next

• Learn more about ACLs.
• Learn how to simplify your access control using uniform bucket-level access.
• Learn about best practices when using ACLs.