Configura y administra políticas de IAM en buckets

Descripción general

En esta página, se describe cómo configurar políticas de Identity and Access Management (IAM) en buckets para que puedas controlar el acceso a los objetos y las carpetas administradas dentro de esos buckets.

Si buscas otros métodos de control de acceso, consulta los siguientes recursos:

Para obtener información sobre cómo obtener un control más preciso sobre los grupos de objetos, consulta Configura y administra políticas de IAM en carpetas administradas.
Para obtener una forma alternativa de controlar el acceso a objetos individuales en los depósitos, consulta Listas de control de acceso.
Para obtener más información sobre cómo controlar el acceso a los recursos de Cloud Storage, consulta Descripción general del control de acceso.

Roles obligatorios

Para obtener los permisos que necesitas a fin de configurar y administrar las políticas de IAM para un bucket, pídele a tu administrador que te otorgue el rol de IAM Administrador de almacenamiento (roles/storage.admin) para el bucket.

Esta función contiene los siguientes permisos, que son necesarios a fin de configurar y administrar las políticas de IAM para los buckets:

storage.buckets.get
storage.buckets.getIamPolicy
storage.buckets.setIamPolicy
storage.buckets.update
storage.buckets.list
- Este permiso solo es necesario si planeas usar la consola de Google Cloud para realizar la tarea en esta página.

También puedes obtener estos permisos con roles personalizados.

Agrega un principal a una política a nivel de bucket

Para obtener una lista de los roles asociados con Cloud Storage, consulta Roles de IAM. Para obtener información de las entidades a las que les otorgas roles de IAM, consulta Identificadores principales.

Console

En la consola de Google Cloud, ve a la página Buckets de Cloud Storage.
Ir a Buckets
En la lista de buckets, haz clic en el nombre del bucket para el que deseas otorgar un rol a una principal.
Selecciona la pestaña Permisos cerca de la parte superior de la página.
Haz clic en el botón Otorgar acceso.

Aparecerá el cuadro de diálogo Agregar principales.
En el campo Nuevas principales, ingresa una o más identidades que necesiten acceso a tu bucket.
Elige un rol (o roles) del menú desplegable Selecciona un rol. Los roles que seleccionas aparecen en el panel con una descripción breve del permiso que otorgan.
Haz clic en Guardar.

Para obtener información sobre cómo ver detalles de errores acerca de operaciones fallidas de Cloud Storage en la consola de Google Cloud, consulta Solución de problemas.

Línea de comandos

Usa el comando buckets add-iam-policy-binding:

gcloud storage buckets add-iam-policy-binding gs://BUCKET_NAME --member=PRINCIPAL_IDENTIFIER --role=IAM_ROLE

Aquí:

BUCKET_NAME es el nombre del bucket al cual le otorgas acceso principal. Por ejemplo, my-bucket.
PRINCIPAL_IDENTIFIER identifica a quién le otorgas acceso al bucket. Por ejemplo, user:jane@gmail.com Para obtener una lista de los formatos de identificador principal, consulta Identificadores principales.
IAM_ROLE es el rol de IAM que le estás otorgando a la principal. Por ejemplo, roles/storage.objectViewer.

Bibliotecas cliente

C++

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage C++.

Para autenticarte en Cloud Storage, configura las credenciales predeterminadas de la aplicación. Si deseas obtener más información, consulta Configura la autenticación para un entorno de desarrollo local.

namespace gcs = ::google::cloud::storage;
using ::google::cloud::StatusOr;
[](gcs::Client client, std::string const& bucket_name,
   std::string const& role, std::string const& member) {
  auto policy = client.GetNativeBucketIamPolicy(
      bucket_name, gcs::RequestedPolicyVersion(3));

  if (!policy) throw std::move(policy).status();

  policy->set_version(3);
  for (auto& binding : policy->bindings()) {
    if (binding.role() != role || binding.has_condition()) {
      continue;
    }
    auto& members = binding.members();
    if (std::find(members.begin(), members.end(), member) == members.end()) {
      members.emplace_back(member);
    }
  }

  auto updated = client.SetNativeBucketIamPolicy(bucket_name, *policy);
  if (!updated) throw std::move(updated).status();

  std::cout << "Updated IAM policy bucket " << bucket_name
            << ". The new policy is " << *updated << "\n";
}

C#

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage C#.


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

public class AddBucketIamMemberSample
{
    public Policy AddBucketIamMember(
        string bucketName = "your-unique-bucket-name",
        string role = "roles/storage.objectViewer",
        string member = "serviceAccount:dev@iam.gserviceaccount.com")
    {
        var storage = StorageClient.Create();
        var policy = storage.GetBucketIamPolicy(bucketName, new GetBucketIamPolicyOptions
        {
            RequestedPolicyVersion = 3
        });
        // Set the policy schema version. For more information, please refer to https://cloud.google.com/iam/docs/policies#versions.
        policy.Version = 3;

        Policy.BindingsData bindingToAdd = new Policy.BindingsData
        {
            Role = role,
            Members = new List<string> { member }
        };

        policy.Bindings.Add(bindingToAdd);
        var bucketIamPolicy = storage.SetBucketIamPolicy(bucketName, policy);
        Console.WriteLine($"Added {member} with role {role} " + $"to {bucketName}");
        return bucketIamPolicy;
    }
}

Go

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Go.

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

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

// addBucketIAMMember adds the bucket IAM member to permission role.
func addBucketIAMMember(w io.Writer, bucketName string) error {
	// bucketName := "bucket-name"
	ctx := context.Background()
	client, err := storage.NewClient(ctx)
	if err != nil {
		return fmt.Errorf("storage.NewClient: %w", err)
	}
	defer client.Close()

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

	bucket := client.Bucket(bucketName)
	policy, err := bucket.IAM().Policy(ctx)
	if err != nil {
		return fmt.Errorf("Bucket(%q).IAM().Policy: %w", bucketName, err)
	}
	// Other valid prefixes are "serviceAccount:", "user:"
	// See the documentation for more values.
	// https://cloud.google.com/storage/docs/access-control/iam
	identity := "group:cloud-logs@google.com"
	var role iam.RoleName = "roles/storage.objectViewer"

	policy.Add(identity, role)
	if err := bucket.IAM().SetPolicy(ctx, policy); err != nil {
		return fmt.Errorf("Bucket(%q).IAM().SetPolicy: %w", bucketName, err)
	}
	// NOTE: It may be necessary to retry this operation if IAM policies are
	// being modified concurrently. SetPolicy will return an error if the policy
	// was modified since it was retrieved.
	fmt.Fprintf(w, "Added %v with role %v to %v\n", identity, role, bucketName)
	return nil
}

Java

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Java.


import com.google.cloud.Binding;
import com.google.cloud.Policy;
import com.google.cloud.storage.Storage;
import com.google.cloud.storage.StorageOptions;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class AddBucketIamMember {
  /** Example of adding a member to the Bucket-level IAM */
  public static void addBucketIamMember(String projectId, String bucketName) {
    // The ID of your GCP project
    // String projectId = "your-project-id";

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

    // For more information please read:
    // https://cloud.google.com/storage/docs/access-control/iam
    Storage storage = StorageOptions.newBuilder().setProjectId(projectId).build().getService();

    Policy originalPolicy =
        storage.getIamPolicy(bucketName, Storage.BucketSourceOption.requestedPolicyVersion(3));

    String role = "roles/storage.objectViewer";
    String member = "group:example@google.com";

    // getBindingsList() returns an ImmutableList and copying over to an ArrayList so it's mutable.
    List<Binding> bindings = new ArrayList(originalPolicy.getBindingsList());

    // Create a new binding using role and member
    Binding.Builder newMemberBindingBuilder = Binding.newBuilder();
    newMemberBindingBuilder.setRole(role).setMembers(Arrays.asList(member));
    bindings.add(newMemberBindingBuilder.build());

    // Update policy to add member
    Policy.Builder updatedPolicyBuilder = originalPolicy.toBuilder();
    updatedPolicyBuilder.setBindings(bindings).setVersion(3);
    Policy updatedPolicy = storage.setIamPolicy(bucketName, updatedPolicyBuilder.build());

    System.out.printf("Added %s with role %s to %s\n", member, role, bucketName);
  }
}

Node.js

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Node.js.

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

// The role to grant
// const roleName = 'roles/storage.objectViewer';

// The members to grant the new role to
// const members = [
//   'user:jdoe@example.com',
//   'group:admins@example.com',
// ];

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

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

async function addBucketIamMember() {
  // Get a reference to a Google Cloud Storage bucket
  const bucket = storage.bucket(bucketName);

  // For more information please read:
  // https://cloud.google.com/storage/docs/access-control/iam
  const [policy] = await bucket.iam.getPolicy({requestedPolicyVersion: 3});

  // Adds the new roles to the bucket's IAM policy
  policy.bindings.push({
    role: roleName,
    members: members,
  });

  // Updates the bucket's IAM policy
  await bucket.iam.setPolicy(policy);

  console.log(
    `Added the following member(s) with role ${roleName} to ${bucketName}:`
  );

  members.forEach(member => {
    console.log(`  ${member}`);
  });
}

addBucketIamMember().catch(console.error);

PHP

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage PHP.

use Google\Cloud\Storage\StorageClient;

/**
 * Adds a new member / role IAM pair to a given Cloud Storage bucket.
 *
 * @param string $bucketName The name of your Cloud Storage bucket.
 *        (e.g. 'my-bucket')
 * @param string $role The role to which the given member should be added.
 *        (e.g. 'roles/storage.objectViewer')
 * @param string[] $members The member(s) to be added to the role.
 *        (e.g. ['group:example@google.com'])
 */
function add_bucket_iam_member(string $bucketName, string $role, array $members): void
{
    $storage = new StorageClient();
    $bucket = $storage->bucket($bucketName);

    $policy = $bucket->iam()->policy(['requestedPolicyVersion' => 3]);
    $policy['version'] = 3;

    $policy['bindings'][] = [
        'role' => $role,
        'members' => $members
    ];

    $bucket->iam()->setPolicy($policy);

    printf('Added the following member(s) to role %s for bucket %s' . PHP_EOL, $role, $bucketName);
    foreach ($members as $member) {
        printf('    %s' . PHP_EOL, $member);
    }
}

Python

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Python.

from google.cloud import storage


def add_bucket_iam_member(bucket_name, role, member):
    """Add a new member to an IAM Policy"""
    # bucket_name = "your-bucket-name"
    # role = "IAM role, e.g., roles/storage.objectViewer"
    # member = "IAM identity, e.g., user: name@example.com"

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

    policy = bucket.get_iam_policy(requested_policy_version=3)

    policy.bindings.append({"role": role, "members": {member}})

    bucket.set_iam_policy(policy)

    print(f"Added {member} with role {role} to {bucket_name}.")

Ruby

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Ruby.

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

  require "google/cloud/storage"

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

  role   = "roles/storage.objectViewer"
  member = "group:example@google.com"

  bucket.policy requested_policy_version: 3 do |policy|
    policy.bindings.insert role: role, members: [member]
  end

  puts "Added #{member} with role #{role} to #{bucket_name}"
end

API de REST

JSON

Tener la gcloud CLI instalada e inicializada a fin de generar un token de acceso para el encabezado Authorization.

Como alternativa, puedes crear un token de acceso con OAuth 2.0 Playground y, luego, incluirlo en el encabezado Authorization.
Crea un archivo JSON que contenga la siguiente información:
```
{
"bindings":[
  {
    "role": "IAM_ROLE",
    "members":[
      "PRINCIPAL_IDENTIFIER"
    ]
  }
]
}
```
Aquí:
- IAM_ROLE es el rol de IAM que deseas otorgar. Por ejemplo, roles/storage.objectViewer.
- PRINCIPAL_IDENTIFIER identifica a quién le otorgas acceso al bucket. Por ejemplo, user:jane@gmail.com Para obtener una lista de los formatos de identificador principal, consulta Identificadores principales.
Usa cURL para llamar a la API de JSON con una solicitud PUT setIamPolicy:
```
curl -X PUT --data-binary @JSON_FILE_NAME \
-H "Authorization: Bearer $(gcloud auth print-access-token)" \
-H "Content-Type: application/json" \
"https://storage.googleapis.com/storage/v1/b/BUCKET_NAME/iam"
```
Aquí:
- JSON_FILE_NAME es la ruta de acceso del archivo que creaste en el paso 2.
- BUCKET_NAME es el nombre del bucket al que le quieres otorgar acceso al principal. Por ejemplo, my-bucket.

Visualiza la política de IAM para un bucket

Console

En la consola de Google Cloud, ve a la página Buckets de Cloud Storage.
Ir a Buckets
En la lista de buckets, haz clic en el nombre del bucket cuya política deseas ver.
En la página Detalles del bucket, haz clic en la pestaña Permisos.

La política de IAM que se aplica al bucket aparece en la sección Permisos.
Opcional: Usa la barra Filtros para filtrar tus resultados.

Si buscas por principal, tus resultados mostrarán cada rol que se otorga al principal.

Línea de comandos

Usa el comando buckets get-iam-policy:

gcloud storage buckets get-iam-policy gs://BUCKET_NAME

En el ejemplo anterior, BUCKET_NAME es el nombre del bucket cuya política de IAM deseas ver. Por ejemplo, my-bucket.

Bibliotecas cliente

C++

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage C++.

namespace gcs = ::google::cloud::storage;
using ::google::cloud::StatusOr;
[](gcs::Client client, std::string const& bucket_name) {
  auto policy = client.GetNativeBucketIamPolicy(
      bucket_name, gcs::RequestedPolicyVersion(3));

  if (!policy) throw std::move(policy).status();
  std::cout << "The IAM policy for bucket " << bucket_name << " is "
            << *policy << "\n";
}

C#

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage C#.


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

public class ViewBucketIamMembersSample
{
    public Policy ViewBucketIamMembers(string bucketName = "your-unique-bucket-name")
    {
        var storage = StorageClient.Create();
        var policy = storage.GetBucketIamPolicy(bucketName, new GetBucketIamPolicyOptions
        {
            RequestedPolicyVersion = 3
        });

        foreach (var binding in policy.Bindings)
        {
            Console.WriteLine($"Role: {binding.Role}");
            Console.WriteLine("Members:");
            foreach (var member in binding.Members)
            {
                Console.WriteLine($"{member}");
            }
        }
        return policy;
    }
}

Go

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Go.

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

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

// getBucketPolicy gets the bucket IAM policy.
func getBucketPolicy(w io.Writer, bucketName string) (*iam.Policy3, error) {
	// bucketName := "bucket-name"
	ctx := context.Background()
	client, err := storage.NewClient(ctx)
	if err != nil {
		return nil, fmt.Errorf("storage.NewClient: %w", err)
	}
	defer client.Close()

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

	policy, err := client.Bucket(bucketName).IAM().V3().Policy(ctx)
	if err != nil {
		return nil, fmt.Errorf("Bucket(%q).IAM().V3().Policy: %w", bucketName, err)
	}
	for _, binding := range policy.Bindings {
		fmt.Fprintf(w, "%q: %q (condition: %v)\n", binding.Role, binding.Members, binding.Condition)
	}
	return policy, nil
}

Java

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Java.

import com.google.cloud.Binding;
import com.google.cloud.Policy;
import com.google.cloud.storage.Storage;
import com.google.cloud.storage.StorageOptions;

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

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

    // For more information please read:
    // https://cloud.google.com/storage/docs/access-control/iam
    Storage storage = StorageOptions.newBuilder().setProjectId(projectId).build().getService();

    Policy policy =
        storage.getIamPolicy(bucketName, Storage.BucketSourceOption.requestedPolicyVersion(3));

    // Print binding information
    for (Binding binding : policy.getBindingsList()) {
      System.out.printf("Role: %s Members: %s\n", binding.getRole(), binding.getMembers());

      // Print condition if one is set
      boolean bindingIsConditional = binding.getCondition() != null;
      if (bindingIsConditional) {
        System.out.printf("Condition Title: %s\n", binding.getCondition().getTitle());
        System.out.printf("Condition Description: %s\n", binding.getCondition().getDescription());
        System.out.printf("Condition Expression: %s\n", binding.getCondition().getExpression());
      }
    }
  }
}

Node.js

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Node.js.

/**
 * 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 viewBucketIamMembers() {
  // For more information please read:
  // https://cloud.google.com/storage/docs/access-control/iam
  const results = await storage
    .bucket(bucketName)
    .iam.getPolicy({requestedPolicyVersion: 3});

  const bindings = results[0].bindings;

  console.log(`Bindings for bucket ${bucketName}:`);
  for (const binding of bindings) {
    console.log(`  Role: ${binding.role}`);
    console.log('  Members:');

    const members = binding.members;
    for (const member of members) {
      console.log(`    ${member}`);
    }

    const condition = binding.condition;
    if (condition) {
      console.log('  Condition:');
      console.log(`    Title: ${condition.title}`);
      console.log(`    Description: ${condition.description}`);
      console.log(`    Expression: ${condition.expression}`);
    }
  }
}

viewBucketIamMembers().catch(console.error);

PHP

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage PHP.

use Google\Cloud\Storage\StorageClient;

/**
 * View Bucket IAM members for a given Cloud Storage bucket.
 *
 * @param string $bucketName The name of your Cloud Storage bucket.
 *        (e.g. 'my-bucket')
 */
function view_bucket_iam_members(string $bucketName): void
{
    $storage = new StorageClient();
    $bucket = $storage->bucket($bucketName);

    $policy = $bucket->iam()->policy(['requestedPolicyVersion' => 3]);

    printf('Printing Bucket IAM members for Bucket: %s' . PHP_EOL, $bucketName);
    printf(PHP_EOL);

    foreach ($policy['bindings'] as $binding) {
        printf('Role: %s' . PHP_EOL, $binding['role']);
        printf('Members:' . PHP_EOL);
        foreach ($binding['members'] as $member) {
            printf('  %s' . PHP_EOL, $member);
        }

        if (isset($binding['condition'])) {
            $condition = $binding['condition'];
            printf('  with condition:' . PHP_EOL);
            printf('    Title: %s' . PHP_EOL, $condition['title']);
            printf('    Description: %s' . PHP_EOL, $condition['description']);
            printf('    Expression: %s' . PHP_EOL, $condition['expression']);
        }
        printf(PHP_EOL);
    }
}

Python

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Python.

from google.cloud import storage


def view_bucket_iam_members(bucket_name):
    """View IAM Policy for a bucket"""
    # bucket_name = "your-bucket-name"

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

    policy = bucket.get_iam_policy(requested_policy_version=3)

    for binding in policy.bindings:
        print(f"Role: {binding['role']}, Members: {binding['members']}")

Ruby

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Ruby.

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

  require "google/cloud/storage"

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

  policy = bucket.policy requested_policy_version: 3
  policy.bindings.each do |binding|
    puts "Role: #{binding.role}"
    puts "Members: #{binding.members}"

    # if a conditional binding exists print the condition.
    if binding.condition
      puts "Condition Title: #{binding.condition.title}"
      puts "Condition Description: #{binding.condition.description}"
      puts "Condition Expression: #{binding.condition.expression}"
    end
  end
end

API de REST

JSON

Tener la gcloud CLI instalada e inicializada a fin de generar un token de acceso para el encabezado Authorization.

Como alternativa, puedes crear un token de acceso con OAuth 2.0 Playground y, luego, incluirlo en el encabezado Authorization.
Usa cURL para llamar a la API de JSON con una solicitud GET getIamPolicy:
```
curl -X GET \
-H "Authorization: Bearer $(gcloud auth print-access-token)" \
"https://storage.googleapis.com/storage/v1/b/BUCKET_NAME/iam"
```
En el ejemplo anterior, BUCKET_NAME es el nombre del bucket cuya política de IAM deseas ver. Por ejemplo, my-bucket.

Quita a un principal de una política de nivel de bucket

Console

En la consola de Google Cloud, ve a la página Buckets de Cloud Storage.
Ir a Buckets
En la lista de buckets, haz clic en el nombre del bucket del que deseas quitar el rol de una principal.
En la página Detalles del bucket, haz clic en la pestaña Permisos.

La política de IAM que se aplica al bucket aparece en la sección Permisos.
En la pestaña Ver por principales, selecciona la casilla de verificación de la principal que deseas quitar.
Haz clic en el botón Quitar acceso.
En la ventana de superposición que aparece, haz clic en Confirmar.

Para obtener información acerca de cómo ver detalles de errores acerca de operaciones fallidas de Cloud Storage en la consola de Google Cloud, consulta Solución de problemas.

Línea de comandos

Usa el comando buckets remove-iam-policy-binding:

gcloud storage buckets remove-iam-policy-binding  gs://BUCKET_NAME --member=PRINCIPAL_IDENTIFIER --role=IAM_ROLE

Aquí:

BUCKET_NAME es el nombre del bucket al que revocas el acceso. Por ejemplo, my-bucket.
PRINCIPAL_IDENTIFIER identifica a quién revocas el acceso. Por ejemplo, user:jane@gmail.com Para obtener una lista de los formatos de identificador principal, consulta Identificadores de principal.
IAM_ROLE es el rol de IAM que estás revocando. Por ejemplo, roles/storage.objectViewer.

Bibliotecas cliente

C++

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage C++.

namespace gcs = ::google::cloud::storage;
using ::google::cloud::StatusOr;
[](gcs::Client client, std::string const& bucket_name,
   std::string const& role, std::string const& member) {
  auto policy = client.GetNativeBucketIamPolicy(
      bucket_name, gcs::RequestedPolicyVersion(3));
  if (!policy) throw std::move(policy).status();

  policy->set_version(3);
  std::vector<google::cloud::storage::NativeIamBinding> updated_bindings;
  for (auto& binding : policy->bindings()) {
    auto& members = binding.members();
    if (binding.role() == role && !binding.has_condition()) {
      members.erase(std::remove(members.begin(), members.end(), member),
                    members.end());
    }
    if (!members.empty()) {
      updated_bindings.emplace_back(std::move(binding));
    }
  }
  policy->bindings() = std::move(updated_bindings);

  auto updated = client.SetNativeBucketIamPolicy(bucket_name, *policy);
  if (!updated) throw std::move(updated).status();

  std::cout << "Updated IAM policy bucket " << bucket_name
            << ". The new policy is " << *updated << "\n";
}

C#

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage C#.


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

public class RemoveBucketIamMemberSample
{
    public void RemoveBucketIamMember(
        string bucketName = "your-unique-bucket-name",
        string role = "roles/storage.objectViewer",
        string member = "serviceAccount:dev@iam.gserviceaccount.com")
    {
        var storage = StorageClient.Create();
        var policy = storage.GetBucketIamPolicy(bucketName, new GetBucketIamPolicyOptions
        {
            RequestedPolicyVersion = 3
        });
        // Set the policy schema version. For more information, please refer to https://cloud.google.com/iam/docs/policies#versions.
        policy.Version = 3;

        foreach (var binding in policy.Bindings.Where(c => c.Role == role).ToList())
        {
            // Remove the role/member combo from the IAM policy.
            binding.Members = binding.Members.Where(m => m != member).ToList();
            // Remove role if it contains no members.
            if (binding.Members.Count == 0)
            {
                policy.Bindings.Remove(binding);
            }
        }
        // Set the modified IAM policy to be the current IAM policy.
        storage.SetBucketIamPolicy(bucketName, policy);
        Console.WriteLine($"Removed {member} with role {role} from {bucketName}");
    }
}

Go

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Go.

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

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

// removeBucketIAMMember removes the bucket IAM member.
func removeBucketIAMMember(w io.Writer, bucketName string) error {
	// bucketName := "bucket-name"
	ctx := context.Background()
	client, err := storage.NewClient(ctx)
	if err != nil {
		return fmt.Errorf("storage.NewClient: %w", err)
	}
	defer client.Close()

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

	bucket := client.Bucket(bucketName)
	policy, err := bucket.IAM().Policy(ctx)
	if err != nil {
		return fmt.Errorf("Bucket(%q).IAM().Policy: %w", bucketName, err)
	}
	// Other valid prefixes are "serviceAccount:", "user:"
	// See the documentation for more values.
	// https://cloud.google.com/storage/docs/access-control/iam
	// member string, role iam.RoleName
	identity := "group:cloud-logs@google.com"
	var role iam.RoleName = "roles/storage.objectViewer"

	policy.Remove(identity, role)
	if err := bucket.IAM().SetPolicy(ctx, policy); err != nil {
		return fmt.Errorf("Bucket(%q).IAM().SetPolicy: %w", bucketName, err)
	}
	// NOTE: It may be necessary to retry this operation if IAM policies are
	// being modified concurrently. SetPolicy will return an error if the policy
	// was modified since it was retrieved.
	fmt.Fprintf(w, "Removed %v with role %v from %v\n", identity, role, bucketName)
	return nil
}

Java

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Java.


import com.google.cloud.Binding;
import com.google.cloud.Policy;
import com.google.cloud.storage.Storage;
import com.google.cloud.storage.StorageOptions;
import java.util.ArrayList;
import java.util.List;

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

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

    // For more information please read:
    // https://cloud.google.com/storage/docs/access-control/iam
    Storage storage = StorageOptions.newBuilder().setProjectId(projectId).build().getService();

    Policy originalPolicy =
        storage.getIamPolicy(bucketName, Storage.BucketSourceOption.requestedPolicyVersion(3));

    String role = "roles/storage.objectViewer";
    String member = "group:example@google.com";

    // getBindingsList() returns an ImmutableList and copying over to an ArrayList so it's mutable.
    List<Binding> bindings = new ArrayList(originalPolicy.getBindingsList());

    // Remove role-member binding without a condition.
    for (int index = 0; index < bindings.size(); index++) {
      Binding binding = bindings.get(index);
      boolean foundRole = binding.getRole().equals(role);
      boolean foundMember = binding.getMembers().contains(member);
      boolean bindingIsNotConditional = binding.getCondition() == null;

      if (foundRole && foundMember && bindingIsNotConditional) {
        bindings.set(index, binding.toBuilder().removeMembers(member).build());
        break;
      }
    }

    // Update policy to remove member
    Policy.Builder updatedPolicyBuilder = originalPolicy.toBuilder();
    updatedPolicyBuilder.setBindings(bindings).setVersion(3);
    Policy updatedPolicy = storage.setIamPolicy(bucketName, updatedPolicyBuilder.build());

    System.out.printf("Removed %s with role %s from %s\n", member, role, bucketName);
  }
}

Node.js

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Node.js.

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

// The role to revoke
// const roleName = 'roles/storage.objectViewer';

// The members to revoke the roles from
// const members = [
//   'user:jdoe@example.com',
//   'group:admins@example.com',
// ];

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

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

async function removeBucketIamMember() {
  // Get a reference to a Google Cloud Storage bucket
  const bucket = storage.bucket(bucketName);

  // For more information please read:
  // https://cloud.google.com/storage/docs/access-control/iam
  const [policy] = await bucket.iam.getPolicy({requestedPolicyVersion: 3});

  // Finds and updates the appropriate role-member group, without a condition.
  const index = policy.bindings.findIndex(
    binding => binding.role === roleName && !binding.condition
  );

  const role = policy.bindings[index];
  if (role) {
    role.members = role.members.filter(
      member => members.indexOf(member) === -1
    );

    // Updates the policy object with the new (or empty) role-member group
    if (role.members.length === 0) {
      policy.bindings.splice(index, 1);
    } else {
      policy.bindings.index = role;
    }

    // Updates the bucket's IAM policy
    await bucket.iam.setPolicy(policy);
  } else {
    // No matching role-member group(s) were found
    throw new Error('No matching role-member group(s) found.');
  }

  console.log(
    `Removed the following member(s) with role ${roleName} from ${bucketName}:`
  );
  members.forEach(member => {
    console.log(`  ${member}`);
  });
}

removeBucketIamMember().catch(console.error);

PHP

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage PHP.

use Google\Cloud\Storage\StorageClient;

/**
 * Removes a member / role IAM pair from a given Cloud Storage bucket.
 *
 * @param string $bucketName The name of your Cloud Storage bucket.
 *        (e.g. 'my-bucket')
 * @param string $role The role from which the specified member should be removed.
 *        (e.g. 'roles/storage.objectViewer')
 * @param string $member The member to be removed from the specified role.
 *        (e.g. 'group:example@google.com')
 */
function remove_bucket_iam_member(string $bucketName, string $role, string $member): void
{
    $storage = new StorageClient();
    $bucket = $storage->bucket($bucketName);
    $iam = $bucket->iam();
    $policy = $iam->policy(['requestedPolicyVersion' => 3]);
    $policy['version'] = 3;

    foreach ($policy['bindings'] as $i => $binding) {
        // This example only removes member from bindings without a condition.
        if ($binding['role'] == $role && !isset($binding['condition'])) {
            $key = array_search($member, $binding['members']);
            if ($key !== false) {
                unset($binding['members'][$key]);

                // If the last member is removed from the binding, clean up the
                // binding.
                if (count($binding['members']) == 0) {
                    unset($policy['bindings'][$i]);
                    // Ensure array keys are sequential, otherwise JSON encodes
                    // the array as an object, which fails when calling the API.
                    $policy['bindings'] = array_values($policy['bindings']);
                } else {
                    // Ensure array keys are sequential, otherwise JSON encodes
                    // the array as an object, which fails when calling the API.
                    $binding['members'] = array_values($binding['members']);
                    $policy['bindings'][$i] = $binding;
                }

                $iam->setPolicy($policy);
                printf('User %s removed from role %s for bucket %s' . PHP_EOL, $member, $role, $bucketName);
                return;
            }
        }
    }

    throw new \RuntimeException('No matching role-member group(s) found.');
}

Python

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Python.

from google.cloud import storage


def remove_bucket_iam_member(bucket_name, role, member):
    """Remove member from bucket IAM Policy"""
    # bucket_name = "your-bucket-name"
    # role = "IAM role, e.g. roles/storage.objectViewer"
    # member = "IAM identity, e.g. user: name@example.com"

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

    policy = bucket.get_iam_policy(requested_policy_version=3)

    for binding in policy.bindings:
        print(binding)
        if binding["role"] == role and binding.get("condition") is None:
            binding["members"].discard(member)

    bucket.set_iam_policy(policy)

    print(f"Removed {member} with role {role} from {bucket_name}.")

Ruby

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Ruby.

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

  # For more information please read: https://cloud.google.com/storage/docs/access-control/iam

  require "google/cloud/storage"

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

  role   = "roles/storage.objectViewer"
  member = "group:example@google.com"

  bucket.policy requested_policy_version: 3 do |policy|
    policy.bindings.each do |binding|
      if binding.role == role && binding.condition.nil?
        binding.members.delete member
      end
    end
  end

  puts "Removed #{member} with role #{role} from #{bucket_name}"
end

API de REST

JSON

Tener la gcloud CLI instalada e inicializada a fin de generar un token de acceso para el encabezado Authorization.

Como alternativa, puedes crear un token de acceso con OAuth 2.0 Playground y, luego, incluirlo en el encabezado Authorization.
Obtén la política existente aplicada a tu bucket. Para ello, usa cURL para llamar a la API de JSON con una solicitud GET getIamPolicy:
```
curl -X GET \
-H "Authorization: Bearer $(gcloud auth print-access-token)" \
"https://storage.googleapis.com/storage/v1/b/BUCKET_NAME/iam"
```
En el ejemplo anterior, BUCKET_NAME es el nombre del bucket cuya política de IAM deseas ver. Por ejemplo, my-bucket.
Crea un archivo JSON que contenga la política que recuperaste en el paso anterior.
Edita el archivo JSON para quitar al miembro de la política.
Usa cURL para llamar a la API de JSON con una solicitud PUT setIamPolicy:
```
curl -X PUT --data-binary @JSON_FILE_NAME \
-H "Authorization: Bearer $(gcloud auth print-access-token)" \
-H "Content-Type: application/json" \
"https://storage.googleapis.com/storage/v1/b/BUCKET_NAME/iam"
```
Aquí:
- JSON_FILE_NAME es la ruta de acceso del archivo que creaste en el paso 3.
- BUCKET_NAME es el nombre del bucket del que deseas quitar el acceso. Por ejemplo, my-bucket.

Usa condiciones de IAM en buckets

En las siguientes secciones, se muestra cómo agregar y quitar Condiciones de IAM en los buckets. Para ver las Condiciones de IAM para tu bucket, consulta Visualiza la política de IAM de un bucket. Si quieres obtener más información del uso de las Condiciones de IAM con Cloud Storage, consulta Condiciones.

Debes habilitar el acceso uniforme a nivel de bucket en el bucket antes de agregar condiciones.

Establece una nueva condición en un bucket

Console

En la consola de Google Cloud, ve a la página Buckets de Cloud Storage.
Ir a Buckets
En la lista de buckets, haz clic en el nombre del bucket al que quieres agregar una condición nueva.
En la página Detalles del bucket, haz clic en la pestaña Permisos.

La política de IAM que se aplica al bucket aparece en la sección Permisos.
Haz clic en + Otorgar acceso.
En Principales nuevos, completa los principales a los que deseas otorgarles acceso a tu bucket.
Para cada rol al que desees aplicar una condición, sigue estos pasos:
1. Selecciona el rol que quieres otorgarles a los principales.
2. Haz clic en Agregar condición para abrir el formulario Editar condición.
3. Completa el Título de la condición. El campo Descripción es opcional.
4. Usa el Creador de condiciones para crear tu condición de forma visual o usa la pestaña Editor de condiciones para ingresar la expresión CEL.
5. Haz clic en Guardar para regresar al formulario Agregar miembros. Para agregar varios roles, haz clic en Agregar otro rol.
Haz clic en Guardar.

Para obtener información sobre cómo ver detalles de errores acerca de operaciones fallidas de Cloud Storage en la consola de Google Cloud, consulta Solución de problemas.

Línea de comandos

Crea un archivo JSON o YAML que defina la condición, incluido el title de la condición, la expression lógica basada en atributos para la condición y, de forma opcional, , una description de la condición.

Ten en cuenta que Cloud Storage solo admite los atributos de fecha/hora ,tipo de recurso y nombre del recurso en el expression.
Usa el comandobuckets add-iam-policy-binding con la marca --condition-from-file:

gcloud storage buckets add-iam-policy-binding  gs://BUCKET_NAME --member=PRINCIPAL_IDENTIFIER --role=IAM_ROLE --condition-from-file=CONDITION_FILE

Aquí:

BUCKET_NAME es el nombre del bucket al cual le otorgas acceso principal. Por ejemplo, my-bucket.
PRINCIPAL_IDENTIFIER identifica a quién se aplica la condición. Por ejemplo, user:jane@gmail.com Para obtener una lista de los formatos de identificador principal, consulta Identificadores principales.
IAM_ROLE es el rol de IAM que le estás otorgando a la principal. Por ejemplo, roles/storage.objectViewer.
CONDITION_FILE es el archivo que creaste en el paso anterior.

Como alternativa, puedes incluir la condición de forma directa en el comando con la marca --condition en lugar de la marca --condition-from-file.

Bibliotecas cliente

C++

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage C++.

namespace gcs = ::google::cloud::storage;
using ::google::cloud::StatusOr;
[](gcs::Client client, std::string const& bucket_name,
   std::string const& role, std::string const& member,
   std::string const& condition_title,
   std::string const& condition_description,
   std::string const& condition_expression) {
  auto policy = client.GetNativeBucketIamPolicy(
      bucket_name, gcs::RequestedPolicyVersion(3));
  if (!policy) throw std::move(policy).status();

  policy->set_version(3);
  policy->bindings().emplace_back(gcs::NativeIamBinding(
      role, {member},
      gcs::NativeExpression(condition_expression, condition_title,
                            condition_description)));

  auto updated = client.SetNativeBucketIamPolicy(bucket_name, *policy);
  if (!updated) throw std::move(updated).status();

  std::cout << "Updated IAM policy bucket " << bucket_name
            << ". The new policy is " << *updated << "\n";

  std::cout << "Added member " << member << " with role " << role << " to "
            << bucket_name << ":\n";
  std::cout << "with condition:\n"
            << "\t Title: " << condition_title << "\n"
            << "\t Description: " << condition_description << "\n"
            << "\t Expression: " << condition_expression << "\n";
}

C#

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage C#.


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

public class AddBucketConditionalIamBindingSample
{
    /// <summary>
    /// Adds a conditional Iam policy to a bucket.
    /// </summary>
    /// <param name="bucketName">The name of the bucket.</param>
    /// <param name="role">The role that members may assume.</param>
    /// <param name="member">The identifier of the member who may assume the provided role.</param>
    /// <param name="title">Title for the expression.</param>
    /// <param name="description">Description of the expression.</param>
    /// <param name="expression">Describes the conditions that need to be met for the policy to be applied.
    /// It's represented as a string using Common Expression Language syntax.</param>
    public Policy AddBucketConditionalIamBinding(
        string bucketName = "your-unique-bucket-name",
        string role = "roles/storage.objectViewer",
        string member = "serviceAccount:dev@iam.gserviceaccount.com",
        string title = "title",
        string description = "description",
        string expression = "resource.name.startsWith(\"projects/_/buckets/bucket-name/objects/prefix-a-\")")
    {
        var storage = StorageClient.Create();
        var policy = storage.GetBucketIamPolicy(bucketName, new GetBucketIamPolicyOptions
        {
            RequestedPolicyVersion = 3
        });
        // Set the policy schema version. For more information, please refer to https://cloud.google.com/iam/docs/policies#versions.
        policy.Version = 3;
        Policy.BindingsData bindingToAdd = new Policy.BindingsData
        {
            Role = role,
            Members = new List<string> { member },
            Condition = new Expr
            {
                Title = title,
                Description = description,
                Expression = expression
            }
        };

        policy.Bindings.Add(bindingToAdd);

        var bucketIamPolicy = storage.SetBucketIamPolicy(bucketName, policy);
        Console.WriteLine($"Added {member} with role {role} " + $"to {bucketName}");
        return bucketIamPolicy;
    }
}

Go

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Go.

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

	"cloud.google.com/go/storage"
	iampb "google.golang.org/genproto/googleapis/iam/v1"
	"google.golang.org/genproto/googleapis/type/expr"
)

// addBucketConditionalIAMBinding adds bucket conditional IAM binding.
func addBucketConditionalIAMBinding(w io.Writer, bucketName, role, member, title, description, expression string) error {
	// bucketName := "bucket-name"
	// role := "bucket-level IAM role"
	// member := "bucket-level IAM member"
	// title := "condition title"
	// description := "condition description"
	// expression := "condition expression"
	ctx := context.Background()
	client, err := storage.NewClient(ctx)
	if err != nil {
		return fmt.Errorf("storage.NewClient: %w", err)
	}
	defer client.Close()

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

	bucket := client.Bucket(bucketName)
	policy, err := bucket.IAM().V3().Policy(ctx)
	if err != nil {
		return fmt.Errorf("Bucket(%q).IAM().V3().Policy: %w", bucketName, err)
	}

	policy.Bindings = append(policy.Bindings, &iampb.Binding{
		Role:    role,
		Members: []string{member},
		Condition: &expr.Expr{
			Title:       title,
			Description: description,
			Expression:  expression,
		},
	})

	if err := bucket.IAM().V3().SetPolicy(ctx, policy); err != nil {
		return fmt.Errorf("Bucket(%q).IAM().V3().SetPolicy: %w", bucketName, err)
	}
	// NOTE: It may be necessary to retry this operation if IAM policies are
	// being modified concurrently. SetPolicy will return an error if the policy
	// was modified since it was retrieved.
	fmt.Fprintf(w, "Added %v with role %v to %v with condition %v %v %v\n", member, role, bucketName, title, description, expression)
	return nil
}

Java

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Java.


import com.google.cloud.Binding;
import com.google.cloud.Condition;
import com.google.cloud.Policy;
import com.google.cloud.storage.Storage;
import com.google.cloud.storage.StorageOptions;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class AddBucketIamConditionalBinding {
  /** Example of adding a conditional binding to the Bucket-level IAM */
  public static void addBucketIamConditionalBinding(String projectId, String bucketName) {
    // The ID of your GCP project
    // String projectId = "your-project-id";

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

    // For more information please read:
    // https://cloud.google.com/storage/docs/access-control/iam
    Storage storage = StorageOptions.newBuilder().setProjectId(projectId).build().getService();

    Policy originalPolicy =
        storage.getIamPolicy(bucketName, Storage.BucketSourceOption.requestedPolicyVersion(3));

    String role = "roles/storage.objectViewer";
    String member = "group:example@google.com";

    // Create a condition
    String conditionTitle = "Title";
    String conditionDescription = "Description";
    String conditionExpression =
        "resource.name.startsWith(\"projects/_/buckets/bucket-name/objects/prefix-a-\")";
    Condition.Builder conditionBuilder = Condition.newBuilder();
    conditionBuilder.setTitle(conditionTitle);
    conditionBuilder.setDescription(conditionDescription);
    conditionBuilder.setExpression(conditionExpression);

    // getBindingsList() returns an ImmutableList, we copy over to an ArrayList so it's mutable
    List<Binding> bindings = new ArrayList(originalPolicy.getBindingsList());

    // Add condition to a binding
    Binding.Builder newBindingBuilder =
        Binding.newBuilder()
            .setRole(role)
            .setMembers(Arrays.asList(member))
            .setCondition(conditionBuilder.build());
    bindings.add(newBindingBuilder.build());

    // Update policy with new conditional binding
    Policy.Builder updatedPolicyBuilder = originalPolicy.toBuilder();
    updatedPolicyBuilder.setBindings(bindings).setVersion(3);

    storage.setIamPolicy(bucketName, updatedPolicyBuilder.build());

    System.out.printf(
        "Added %s with role %s to %s with condition %s %s %s\n",
        member, role, bucketName, conditionTitle, conditionDescription, conditionExpression);
  }
}

Node.js

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Node.js.

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

// The role to grant
// const roleName = 'roles/storage.objectViewer';

// The members to grant the new role to
// const members = [
//   'user:jdoe@example.com',
//   'group:admins@example.com',
// ];

// Create a condition
// const title = 'Title';
// const description = 'Description';
// const expression = 'resource.name.startsWith(\"projects/_/buckets/bucket-name/objects/prefix-a-\")';

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

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

async function addBucketConditionalBinding() {
  // Get a reference to a Google Cloud Storage bucket
  const bucket = storage.bucket(bucketName);

  // Gets and updates the bucket's IAM policy
  const [policy] = await bucket.iam.getPolicy({requestedPolicyVersion: 3});

  // Set the policy's version to 3 to use condition in bindings.
  policy.version = 3;

  // Adds the new roles to the bucket's IAM policy
  policy.bindings.push({
    role: roleName,
    members: members,
    condition: {
      title: title,
      description: description,
      expression: expression,
    },
  });

  // Updates the bucket's IAM policy
  await bucket.iam.setPolicy(policy);

  console.log(
    `Added the following member(s) with role ${roleName} to ${bucketName}:`
  );

  members.forEach(member => {
    console.log(`  ${member}`);
  });

  console.log('with condition:');
  console.log(`  Title: ${title}`);
  console.log(`  Description: ${description}`);
  console.log(`  Expression: ${expression}`);
}

addBucketConditionalBinding().catch(console.error);

PHP

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage PHP.

use Google\Cloud\Storage\StorageClient;

/**
 * Adds a conditional IAM binding to a bucket's IAM policy.
 *
 * @param string $bucketName The name of your Cloud Storage bucket.
 *        (e.g. 'my-bucket')
 * @param string $role The role that will be given to members in this binding.
 *        (e.g. 'roles/storage.objectViewer')
 * @param string[] $members The member(s) associated with this binding.
 *        (e.g. ['group:example@google.com'])
 * @param string $title The title of the condition. (e.g. 'Title')
 * @param string $description The description of the condition.
 *        (e.g. 'Condition Description')
 * @param string $expression The condition specified in CEL expression language.
 *        (e.g. 'resource.name.startsWith("projects/_/buckets/bucket-name/objects/prefix-a-")')
 *
 * To see how to express a condition in CEL, visit:
 * @see https://cloud.google.com/storage/docs/access-control/iam#conditions.
 */
function add_bucket_conditional_iam_binding(string $bucketName, string $role, array $members, string $title, string $description, string $expression): void
{
    $storage = new StorageClient();
    $bucket = $storage->bucket($bucketName);

    $policy = $bucket->iam()->policy(['requestedPolicyVersion' => 3]);

    $policy['version'] = 3;

    $policy['bindings'][] = [
        'role' => $role,
        'members' => $members,
        'condition' => [
            'title' => $title,
            'description' => $description,
            'expression' => $expression,
        ],
    ];

    $bucket->iam()->setPolicy($policy);

    printf('Added the following member(s) with role %s to %s:' . PHP_EOL, $role, $bucketName);
    foreach ($members as $member) {
        printf('    %s' . PHP_EOL, $member);
    }
    printf('with condition:' . PHP_EOL);
    printf('    Title: %s' . PHP_EOL, $title);
    printf('    Description: %s' . PHP_EOL, $description);
    printf('    Expression: %s' . PHP_EOL, $expression);
}

Python

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Python.

from google.cloud import storage


def add_bucket_conditional_iam_binding(
    bucket_name, role, title, description, expression, members
):
    """Add a conditional IAM binding to a bucket's IAM policy."""
    # bucket_name = "your-bucket-name"
    # role = "IAM role, e.g. roles/storage.objectViewer"
    # members = {"IAM identity, e.g. user: name@example.com}"
    # title = "Condition title."
    # description = "Condition description."
    # expression = "Condition expression."

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

    policy = bucket.get_iam_policy(requested_policy_version=3)

    # Set the policy's version to 3 to use condition in bindings.
    policy.version = 3

    policy.bindings.append(
        {
            "role": role,
            "members": members,
            "condition": {
                "title": title,
                "description": description,
                "expression": expression,
            },
        }
    )

    bucket.set_iam_policy(policy)

    print(f"Added the following member(s) with role {role} to {bucket_name}:")

    for member in members:
        print(f"    {member}")

    print("with condition:")
    print(f"    Title: {title}")
    print(f"    Description: {description}")
    print(f"    Expression: {expression}")

Ruby

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Ruby.

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

  require "google/cloud/storage"

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

  role        = "roles/storage.objectViewer"
  member      = "group:example@google.com"
  title       = "Title"
  description = "Description"
  expression  = "resource.name.startsWith(\"projects/_/buckets/bucket-name/objects/prefix-a-\")"

  bucket.policy requested_policy_version: 3 do |policy|
    policy.version = 3
    policy.bindings.insert(
      role:      role,
      members:   member,
      condition: {
        title:       title,
        description: description,
        expression:  expression
      }
    )
  end

  puts "Added #{member} with role #{role} to #{bucket_name} with condition #{title} #{description} #{expression}"
end

API de REST

JSON

Tener la gcloud CLI instalada e inicializada a fin de generar un token de acceso para el encabezado Authorization.

Como alternativa, puedes crear un token de acceso con OAuth 2.0 Playground y, luego, incluirlo en el encabezado Authorization.
Usa una solicitud GET getIamPolicy para guardar la política de IAM del bucket en un archivo JSON temporal:
```
curl \
'https://storage.googleapis.com/storage/v1/b/BUCKET_NAME/iam' \
--header 'Authorization: Bearer $(gcloud auth print-access-token)' > tmp-policy.json
```
En el ejemplo anterior, BUCKET_NAME es el nombre del bucket correspondiente. Por ejemplo, my-bucket.
Edita el archivo tmp-policy.json en un editor de texto para agregar condiciones nuevas a las vinculaciones en la política de IAM:
```
{
    "version": VERSION,
    "bindings": [
      {
        "role": "IAM_ROLE",
        "members": [
          "PRINCIPAL_IDENTIFIER"
        ],
        "condition": {
          "title": "TITLE",
          "description": "DESCRIPTION",
          "expression": "EXPRESSION"
        }
      }
    ],
    "etag": "ETAG"
}
```
Aquí:
- VERSION es la versión de la política de IAM, que debe ser 3 para los buckets con Condiciones de IAM.
- IAM_ROLE es el rol al que se aplica la condición. Por ejemplo, roles/storage.objectViewer.
- PRINCIPAL_IDENTIFIER identifica a quién se aplica la condición. Por ejemplo, user:jane@gmail.com Para obtener una lista de los formatos de identificador principal, consulta Identificadores de principal.
- TITLE es el título de la condición. Por ejemplo, expires in 2019.
- DESCRIPTION es una descripción opcional de la condición. Por ejemplo, Permission revoked on New Year's
- EXPRESSION es una expresión lógica basada en atributos. Por ejemplo, request.time < timestamp(\"2019-01-01T00:00:00Z\"). Si quieres obtener más ejemplos de expresiones, consulta la referencia de atributos para las Condiciones. Ten en cuenta que Cloud Storage solo admite los atributos de fecha y hora, tipo de recurso y nombre de recurso.
No modifiques ETAG.

Usa una solicitud PUT setIamPolicy para establecer la política de IAM modificada en el bucket:

curl -X PUT --data-binary @tmp-policy.json \
-H "Authorization: Bearer $(gcloud auth print-access-token)" \
-H "Content-Type: application/json" \
"https://storage.googleapis.com/storage/v1/b/BUCKET_NAME/iam"

En el ejemplo anterior, BUCKET_NAME es el nombre del bucket correspondiente. Por ejemplo, my-bucket.

Quita una condición de un bucket

Console

En la consola de Google Cloud, ve a la página Buckets de Cloud Storage.
Ir a Buckets
En la lista de buckets, haz clic en el nombre del bucket al que deseas quitar una condición.
En la página Detalles del bucket, haz clic en la pestaña Permisos.

La política de IAM que se aplica al bucket aparece en la sección Permisos.
Haz clic en el ícono Editar del principal asociado con la condición.
En la superposición Editar acceso que aparece, haz clic en el nombre de la condición que deseas borrar.
En la superposición Editar condición que aparece, haz clic en Borrar y, luego, en Confirmar.
Haz clic en Guardar.

Para obtener información sobre cómo ver detalles de errores acerca de operaciones fallidas de Cloud Storage en la consola de Google Cloud, consulta Solución de problemas.

Línea de comandos

Usa el comando buckets get-iam-policy para guardar la política de IAM del bucket en un archivo JSON temporal.
```
gcloud storage buckets get-iam-policy gs://BUCKET_NAME > tmp-policy.json
```
Edita el archivo tmp-policy.json en un editor de texto para quitar las condiciones de la política de IAM.
Usa buckets set-iam-policy para establecer la política de IAM modificada en el bucket.
```
gcloud storage buckets set-iam-policy gs://BUCKET_NAME tmp-policy.json
```

Muestras de código

C++

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage C++.

namespace gcs = ::google::cloud::storage;
using ::google::cloud::StatusOr;
[](gcs::Client client, std::string const& bucket_name,
   std::string const& role, std::string const& condition_title,
   std::string const& condition_description,
   std::string const& condition_expression) {
  auto policy = client.GetNativeBucketIamPolicy(
      bucket_name, gcs::RequestedPolicyVersion(3));
  if (!policy) throw std::move(policy).status();

  policy->set_version(3);
  auto& bindings = policy->bindings();
  auto e = std::remove_if(
      bindings.begin(), bindings.end(),
      [role, condition_title, condition_description,
       condition_expression](gcs::NativeIamBinding b) {
        return (b.role() == role && b.has_condition() &&
                b.condition().title() == condition_title &&
                b.condition().description() == condition_description &&
                b.condition().expression() == condition_expression);
      });
  if (e == bindings.end()) {
    std::cout << "No matching binding group found.\n";
    return;
  }
  bindings.erase(e);
  auto updated = client.SetNativeBucketIamPolicy(bucket_name, *policy);
  if (!updated) throw std::move(updated).status();

  std::cout << "Conditional binding was removed.\n";
}

C#

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage C#.


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

public class RemoveBucketConditionalIamBindingSample
{
    public Policy RemoveBucketConditionalIamBinding(
        string bucketName = "your-unique-bucket-name",
        string role = "roles/storage.objectViewer",
        string title = "title",
        string description = "description",
        string expression = "resource.name.startsWith(\"projects/_/buckets/bucket-name/objects/prefix-a-\")")
    {
        var storage = StorageClient.Create();
        var policy = storage.GetBucketIamPolicy(bucketName, new GetBucketIamPolicyOptions
        {
            RequestedPolicyVersion = 3
        });
        // Set the policy schema version. For more information, please refer to https://cloud.google.com/iam/docs/policies#versions.
        policy.Version = 3;

        var bindingsToRemove = policy.Bindings.Where(binding => binding.Role == role
              && binding.Condition != null
              && binding.Condition.Title == title
              && binding.Condition.Description == description
              && binding.Condition.Expression == expression).ToList();
        if (bindingsToRemove.Count() > 0)
        {
            foreach (var binding in bindingsToRemove)
            {
                policy.Bindings.Remove(binding);
            }
            // Set the modified IAM policy to be the current IAM policy.
            policy = storage.SetBucketIamPolicy(bucketName, policy);
            Console.WriteLine("Conditional Binding was removed.");
        }
        else
        {
            Console.WriteLine("No matching conditional binding found.");
        }
        return policy;
    }
}

Go

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Go.

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

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

// removeBucketConditionalIAMBinding removes bucket conditional IAM binding.
func removeBucketConditionalIAMBinding(w io.Writer, bucketName, role, title, description, expression string) error {
	// bucketName := "bucket-name"
	// role := "bucket-level IAM role"
	// title := "condition title"
	// description := "condition description"
	// expression := "condition expression"
	ctx := context.Background()
	client, err := storage.NewClient(ctx)
	if err != nil {
		return fmt.Errorf("storage.NewClient: %w", err)
	}
	defer client.Close()

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

	bucket := client.Bucket(bucketName)
	policy, err := bucket.IAM().V3().Policy(ctx)
	if err != nil {
		return fmt.Errorf("Bucket(%q).IAM().V3().Policy: %w", bucketName, err)
	}

	// Find the index of the binding matching inputs.
	i := -1
	for j, binding := range policy.Bindings {
		if binding.Role == role && binding.Condition != nil {
			condition := binding.Condition
			if condition.Title == title &&
				condition.Description == description &&
				condition.Expression == expression {
				i = j
			}
		}
	}

	if i == -1 {
		return fmt.Errorf("no matching binding group found")
	}

	// Get a slice of the bindings, removing the binding at index i.
	policy.Bindings = append(policy.Bindings[:i], policy.Bindings[i+1:]...)

	if err := bucket.IAM().V3().SetPolicy(ctx, policy); err != nil {
		return fmt.Errorf("Bucket(%q).IAM().V3().SetPolicy: %w", bucketName, err)
	}
	// NOTE: It may be necessary to retry this operation if IAM policies are
	// being modified concurrently. SetPolicy will return an error if the policy
	// was modified since it was retrieved.
	fmt.Fprintln(w, "Conditional binding was removed")
	return nil
}

Java

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Java.


import com.google.cloud.Binding;
import com.google.cloud.Condition;
import com.google.cloud.Policy;
import com.google.cloud.storage.Storage;
import com.google.cloud.storage.StorageOptions;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

public class RemoveBucketIamConditionalBinding {
  /** Example of removing a conditional binding to the Bucket-level IAM */
  public static void removeBucketIamConditionalBinding(String projectId, String bucketName) {
    // The ID of your GCP project
    // String projectId = "your-project-id";

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

    // For more information please read:
    // https://cloud.google.com/storage/docs/access-control/iam
    Storage storage = StorageOptions.newBuilder().setProjectId(projectId).build().getService();

    Policy originalPolicy =
        storage.getIamPolicy(bucketName, Storage.BucketSourceOption.requestedPolicyVersion(3));

    String role = "roles/storage.objectViewer";

    // getBindingsList() returns an ImmutableList and copying over to an ArrayList so it's mutable.
    List<Binding> bindings = new ArrayList(originalPolicy.getBindingsList());

    // Create a condition to compare against
    Condition.Builder conditionBuilder = Condition.newBuilder();
    conditionBuilder.setTitle("Title");
    conditionBuilder.setDescription("Description");
    conditionBuilder.setExpression(
        "resource.name.startsWith(\"projects/_/buckets/bucket-name/objects/prefix-a-\")");

    Iterator iterator = bindings.iterator();
    while (iterator.hasNext()) {
      Binding binding = (Binding) iterator.next();
      boolean foundRole = binding.getRole().equals(role);
      boolean conditionsEqual = conditionBuilder.build().equals(binding.getCondition());

      // Remove condition when the role and condition are equal
      if (foundRole && conditionsEqual) {
        iterator.remove();
        break;
      }
    }

    // Update policy to remove conditional binding
    Policy.Builder updatedPolicyBuilder = originalPolicy.toBuilder();
    updatedPolicyBuilder.setBindings(bindings).setVersion(3);
    Policy updatedPolicy = storage.setIamPolicy(bucketName, updatedPolicyBuilder.build());

    System.out.println("Conditional Binding was removed.");
  }
}

Node.js

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Node.js.

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

// The role to grant
// const roleName = 'roles/storage.objectViewer';

// The members to grant the new role to
// const members = [
//   'user:jdoe@example.com',
//   'group:admins@example.com',
// ];

// Create a condition
// const title = 'Title';
// const description = 'Description';
// const expression = 'resource.name.startsWith(\"projects/_/buckets/bucket-name/objects/prefix-a-\")';

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

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

async function removeBucketConditionalBinding() {
  // Get a reference to a Google Cloud Storage bucket
  const bucket = storage.bucket(bucketName);

  // Gets and updates the bucket's IAM policy
  const [policy] = await bucket.iam.getPolicy({requestedPolicyVersion: 3});

  // Set the policy's version to 3 to use condition in bindings.
  policy.version = 3;

  // Finds and removes the appropriate role-member group with specific condition.
  const index = policy.bindings.findIndex(
    binding =>
      binding.role === roleName &&
      binding.condition &&
      binding.condition.title === title &&
      binding.condition.description === description &&
      binding.condition.expression === expression
  );

  const binding = policy.bindings[index];
  if (binding) {
    policy.bindings.splice(index, 1);

    // Updates the bucket's IAM policy
    await bucket.iam.setPolicy(policy);

    console.log('Conditional Binding was removed.');
  } else {
    // No matching role-member group with specific condition were found
    throw new Error('No matching binding group found.');
  }
}

removeBucketConditionalBinding().catch(console.error);

PHP

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage PHP.

use Google\Cloud\Storage\StorageClient;

/**
 * Removes a conditional IAM binding from a bucket's IAM policy.
 *
 * To see how to express a condition in CEL, visit:
 * @see https://cloud.google.com/storage/docs/access-control/iam#conditions.
 *
 * @param string $bucketName The name of your Cloud Storage bucket.
 *        (e.g. 'my-bucket')
 * @param string $role the role that will be given to members in this binding.
 *        (e.g. 'roles/storage.objectViewer')
 * @param string $title The title of the condition. (e.g. 'Title')
 * @param string $description The description of the condition.
 *        (e.g. 'Condition Description')
 * @param string $expression Te condition specified in CEL expression language.
 *        (e.g. 'resource.name.startsWith("projects/_/buckets/bucket-name/objects/prefix-a-")')
 */
function remove_bucket_conditional_iam_binding(string $bucketName, string $role, string $title, string $description, string $expression): void
{
    $storage = new StorageClient();
    $bucket = $storage->bucket($bucketName);

    $policy = $bucket->iam()->policy(['requestedPolicyVersion' => 3]);

    $policy['version'] = 3;

    $key_of_conditional_binding = null;
    foreach ($policy['bindings'] as $key => $binding) {
        if ($binding['role'] == $role && isset($binding['condition'])) {
            $condition = $binding['condition'];
            if ($condition['title'] == $title
                 && $condition['description'] == $description
                 && $condition['expression'] == $expression) {
                $key_of_conditional_binding = $key;
                break;
            }
        }
    }

    if ($key_of_conditional_binding != null) {
        unset($policy['bindings'][$key_of_conditional_binding]);
        // Ensure array keys are sequential, otherwise JSON encodes
        // the array as an object, which fails when calling the API.
        $policy['bindings'] = array_values($policy['bindings']);
        $bucket->iam()->setPolicy($policy);
        print('Conditional Binding was removed.' . PHP_EOL);
    } else {
        print('No matching conditional binding found.' . PHP_EOL);
    }
}

Python

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Python.

from google.cloud import storage


def remove_bucket_conditional_iam_binding(
    bucket_name, role, title, description, expression
):
    """Remove a conditional IAM binding from a bucket's IAM policy."""
    # bucket_name = "your-bucket-name"
    # role = "IAM role, e.g. roles/storage.objectViewer"
    # title = "Condition title."
    # description = "Condition description."
    # expression = "Condition expression."

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

    policy = bucket.get_iam_policy(requested_policy_version=3)

    # Set the policy's version to 3 to use condition in bindings.
    policy.version = 3

    condition = {
        "title": title,
        "description": description,
        "expression": expression,
    }
    policy.bindings = [
        binding
        for binding in policy.bindings
        if not (binding["role"] == role and binding.get("condition") == condition)
    ]

    bucket.set_iam_policy(policy)

    print("Conditional Binding was removed.")

Ruby

Si deseas obtener más información, consulta la documentación de referencia de la API de Cloud Storage Ruby.

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

  require "google/cloud/storage"

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

  role        = "roles/storage.objectViewer"
  title       = "Title"
  description = "Description"
  expression  = "resource.name.startsWith(\"projects/_/buckets/bucket-name/objects/prefix-a-\")"

  bucket.policy requested_policy_version: 3 do |policy|
    policy.version = 3

    binding_to_remove = nil
    policy.bindings.each do |b|
      condition = {
        title:       title,
        description: description,
        expression:  expression
      }
      if (b.role == role) && (b.condition &&
        b.condition.title == title &&
        b.condition.description == description &&
        b.condition.expression == expression)
        binding_to_remove = b
      end
    end
    if binding_to_remove
      policy.bindings.remove binding_to_remove
      puts "Conditional Binding was removed."
    else
      puts "No matching conditional binding found."
    end
  end
end

API de REST

JSON

Tener la gcloud CLI instalada e inicializada a fin de generar un token de acceso para el encabezado Authorization.

Como alternativa, puedes crear un token de acceso con OAuth 2.0 Playground y, luego, incluirlo en el encabezado Authorization.
Usa una solicitud GET getIamPolicy para guardar la política de IAM del bucket en un archivo JSON temporal:
```
curl \
'https://storage.googleapis.com/storage/v1/b/BUCKET_NAME/iam' \
--header 'Authorization: Bearer $(gcloud auth print-access-token)' > tmp-policy.json
```
En el que BUCKET_NAME es el nombre del bucket al que le otorgas acceso. Por ejemplo, my-bucket.
Edita el archivo tmp-policy.json en un editor de texto para quitar las condiciones de la política de IAM.

Usa una solicitud PUT setIamPolicy para establecer la política de IAM modificada en el bucket:

curl -X PUT --data-binary @tmp-policy.json \
-H "Authorization: Bearer $(gcloud auth print-access-token)" \
-H "Content-Type: application/json" \
"https://storage.googleapis.com/storage/v1/b/BUCKET_NAME/iam"

En el ejemplo anterior, BUCKET_NAME es el nombre del bucket cuya política de IAM deseas ver. Por ejemplo, my-bucket.

Prácticas recomendadas

Debes establecer el rol mínimo necesario para otorgar al principal el acceso requerido. Por ejemplo, si un miembro del equipo solo necesita leer los objetos almacenados en un bucket, otórgale la función de visualizador de objetos de almacenamiento (roles/storage.objectViewer) en lugar de la función de administrador de objetos de almacenamiento (roles/storage.objectAdmin). ). Del mismo modo, si el miembro del equipo necesita el control total de los objetos en el bucket, pero no del bucket en sí, otórgale el Administrador de objetos de almacenamiento (roles/storage.objectAdmin ) en lugar de la función de administrador de almacenamiento (roles/storage.admin ).

¿Qué sigue?

Aprende cómo compartir tus datos de forma pública.
Consulta Ejemplos de colaboración y uso compartido específicos.
Obtén información de las prácticas recomendadas para usar IAM.
Obtén más información acerca de cómo usar las recomendaciones de roles para los buckets.
Para solucionar problemas de operaciones fallidas relacionadas con los roles y los permisos de IAM, consulta Solución de problemas.