Update a policy

Demonstrates updating a policy.

Explore further

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

• Manage access to projects, folders, and organizations

Code sample

C++

To learn how to install and use the client library for IAM, see IAM client libraries. For more information, see the IAM C++ API reference documentation.

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

namespace iam = ::google::cloud::iam_admin_v1;
[](std::string const& name) {
  iam::IAMClient client(iam::MakeIAMConnection());
  auto response =
      client.SetIamPolicy(name, [](google::iam::v1::Policy policy) {
        // change the policy, e.g., add/remove/edit a binding
        return policy;
      });
  if (!response) throw std::move(response).status();
  std::cout << "Policy successfully set: " << response->DebugString() << "\n";
}

C#

To learn how to install and use the client library for IAM, see IAM client libraries. For more information, see the IAM C# API reference documentation.

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

using Google.Apis.Auth.OAuth2;
using Google.Apis.CloudResourceManager.v1;
using Google.Apis.CloudResourceManager.v1.Data;

public partial class AccessManager
{
    public static Policy SetPolicy(string projectId, Policy policy)
    {
        var credential = GoogleCredential.GetApplicationDefault()
            .CreateScoped(CloudResourceManagerService.Scope.CloudPlatform);
        var service = new CloudResourceManagerService(
            new CloudResourceManagerService.Initializer
            {
                HttpClientInitializer = credential
            });

        return service.Projects.SetIamPolicy(new SetIamPolicyRequest
        {
            Policy = policy
        }, projectId).Execute();
    }
}

Java

To learn how to install and use the client library for IAM, see IAM client libraries. For more information, see the IAM Java API reference documentation.

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

import com.google.cloud.resourcemanager.v3.ProjectsClient;
import com.google.iam.admin.v1.ProjectName;
import com.google.iam.v1.Policy;
import com.google.iam.v1.SetIamPolicyRequest;
import com.google.protobuf.FieldMask;
import java.io.IOException;
import java.util.Arrays;
import java.util.List;

public class SetProjectPolicy {
  public static void main(String[] args) throws IOException {
    // TODO(developer): Replace the variables before running the sample.
    // TODO: Replace with your project ID.
    String projectId = "your-project-id";
    // TODO: Replace with your policy, GetPolicy.getPolicy(projectId, serviceAccount).
    Policy policy = Policy.newBuilder().build();

    setProjectPolicy(policy, projectId);
  }

  // Sets a project's policy.
  public static Policy setProjectPolicy(Policy policy, String projectId)
          throws IOException {

    // Initialize client that will be used to send requests.
    // This client only needs to be created once, and can be reused for multiple requests.
    try (ProjectsClient projectsClient = ProjectsClient.create()) {
      List<String> paths = Arrays.asList("bindings", "etag");
      SetIamPolicyRequest request = SetIamPolicyRequest.newBuilder()
              .setResource(ProjectName.of(projectId).toString())
              .setPolicy(policy)
              // A FieldMask specifying which fields of the policy to modify. Only
              // the fields in the mask will be modified. If no mask is provided, the
              // following default mask is used:
              // `paths: "bindings, etag"`
              .setUpdateMask(FieldMask.newBuilder().addAllPaths(paths).build())
              .build();

      return projectsClient.setIamPolicy(request);
    }
  }
}

Python

To learn how to install and use the client library for IAM, see IAM client libraries. For more information, see the IAM Python API reference documentation.

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

def set_policy(project_id: str, policy: dict) -> dict:
    """Sets IAM policy for a project."""

    credentials = service_account.Credentials.from_service_account_file(
        filename=os.environ["GOOGLE_APPLICATION_CREDENTIALS"],
        scopes=["https://www.googleapis.com/auth/cloud-platform"],
    )
    service = googleapiclient.discovery.build(
        "cloudresourcemanager", "v1", credentials=credentials
    )

    policy = (
        service.projects()
        .setIamPolicy(resource=project_id, body={"policy": policy})
        .execute()
    )
    print(policy)
    return policy

What's next

To search and filter code samples for other Google Cloud products, see the Google Cloud sample browser.