Rifiutare l'accesso alle risorse

data "google_project" "default" {
}

# Create a service account
resource "google_service_account" "default" {
  display_name = "IAM Deny Example - Service Account"
  account_id   = "example-sa"
  project      = data.google_project.default.project_id
}

# Create an IAM deny policy that denies a permission for the service account
resource "google_iam_deny_policy" "default" {
  provider     = google-beta
  parent       = urlencode("cloudresourcemanager.googleapis.com/projects/${data.google_project.default.project_id}")
  name         = "my-deny-policy"
  display_name = "My deny policy."
  rules {
    deny_rule {
      denied_principals  = ["principal://iam.googleapis.com/projects/-/serviceAccounts/${google_service_account.default.email}"]
      denied_permissions = ["iam.googleapis.com/roles.create"]
    }
  }
}

import (
	"context"
	"fmt"
	"io"

	iam "cloud.google.com/go/iam/apiv2"
	"cloud.google.com/go/iam/apiv2/iampb"

	"google.golang.org/genproto/googleapis/type/expr"
)

// createDenyPolicy creates a deny policy.
func createDenyPolicy(w io.Writer, projectID, policyID string) error {
	// You can add deny policies to organizations, folders, and projects.
	// Each of these resources can have up to 5 deny policies.
	// Deny policies contain deny rules, which specify the following:
	// 1. The permissions to deny and/or exempt.
	// 2. The principals that are denied, or exempted from denial.
	// 3. An optional condition on when to enforce the deny rules.

	// projectID := "your_project_id"
	// policyID := "your_policy_id"

	ctx := context.Background()
	policiesClient, err := iam.NewPoliciesClient(ctx)
	if err != nil {
		return fmt.Errorf("NewPoliciesClient: %w", err)
	}
	defer policiesClient.Close()

	// Each deny policy is attached to an organization, folder, or project.
	// To work with deny policies, specify the attachment point.
	//
	// Its format can be one of the following:
	// 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
	// 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
	// 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
	//
	// The attachment point is identified by its URL-encoded resource name. Hence, replace
	// the "/" with "%%2F".
	attachmentPoint := fmt.Sprintf(
		"cloudresourcemanager.googleapis.com%%2Fprojects%%2F%s",
		projectID,
	)

	denyRule := &iampb.DenyRule{
		// Add one or more principals who should be denied the permissions specified in this rule.
		// For more information on allowed values,
		// see: https://cloud.google.com/iam/help/deny/principal-identifiers
		DeniedPrincipals: []string{"principalSet://goog/public:all"},
		// Optionally, set the principals who should be exempted from the
		// list of denied principals. For example, if you want to deny certain permissions
		// to a group but exempt a few principals, then add those here.
		// ExceptionPrincipals: []string{"principalSet://goog/group/project-admins@example.com"},
		//
		// Set the permissions to deny.
		// The permission value is of the format: service_fqdn/resource.action
		// For the list of supported permissions,
		// see: https://cloud.google.com/iam/help/deny/supported-permissions
		DeniedPermissions: []string{"cloudresourcemanager.googleapis.com/projects.delete"},
		// Optionally, add the permissions to be exempted from this rule.
		// Meaning, the deny rule will not be applicable to these permissions.
		// ExceptionPermissions: []string{"cloudresourcemanager.googleapis.com/projects.create"},
		//
		// Set the condition which will enforce the deny rule.
		// If this condition is true, the deny rule will be applicable.
		// Else, the rule will not be enforced.
		// The expression uses Common Expression Language syntax (CEL).
		// Here we block access based on tags.
		//
		// Here, we create a deny rule that denies the
		// cloudresourcemanager.googleapis.com/projects.delete permission
		// to everyone except project-admins@example.com for resources that are tagged test.
		// A tag is a key-value pair that can be attached to an organization, folder, or project.
		// For more info, see: https://cloud.google.com/iam/docs/deny-access#create-deny-policy
		DenialCondition: &expr.Expr{
			Expression: "!resource.matchTag('12345678/env', 'test')",
		},
	}

	// Add the deny rule and a description for it.
	policyRule := &iampb.PolicyRule{
		Description: "block all principals from deleting projects, unless the principal is a member of project-admins@example.com and the project being deleted has a tag with the value test",
		Kind: &iampb.PolicyRule_DenyRule{
			DenyRule: denyRule,
		},
	}

	policy := &iampb.Policy{
		DisplayName: "Restrict project deletion access",
		Rules:       [](*iampb.PolicyRule){policyRule},
	}

	req := &iampb.CreatePolicyRequest{
		// Construct the full path of the resource's deny policies.
		// Its format is: "policies/ATTACHMENT_POINT/denypolicies"
		Parent:   fmt.Sprintf("policies/%s/denypolicies", attachmentPoint),
		Policy:   policy,
		PolicyId: policyID,
	}
	op, err := policiesClient.CreatePolicy(ctx, req)
	if err != nil {
		return fmt.Errorf("unable to create policy: %w", err)
	}

	policy, err = op.Wait(ctx)
	if err != nil {
		return fmt.Errorf("unable to wait for the operation: %w", err)
	}

	fmt.Fprintf(w, "Policy %s created\n", policy.GetName())

	return nil
}

import com.google.iam.v2.CreatePolicyRequest;
import com.google.iam.v2.DenyRule;
import com.google.iam.v2.PoliciesClient;
import com.google.iam.v2.Policy;
import com.google.iam.v2.PolicyRule;
import com.google.longrunning.Operation;
import com.google.type.Expr;
import java.io.IOException;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

public class CreateDenyPolicy {

  public static void main(String[] args)
      throws IOException, ExecutionException, InterruptedException, TimeoutException {
    // TODO(developer): Replace these variables before running the sample.
    // ID or number of the Google Cloud project you want to use.
    String projectId = "your-google-cloud-project-id";

    // Specify the id of the Deny policy you want to create.
    String policyId = "deny-policy-id";

    createDenyPolicy(projectId, policyId);
  }

  // Create a deny policy.
  // You can add deny policies to organizations, folders, and projects.
  // Each of these resources can have up to 5 deny policies.
  //
  // Deny policies contain deny rules, which specify the following:
  // 1. The permissions to deny and/or exempt.
  // 2. The principals that are denied, or exempted from denial.
  // 3. An optional condition on when to enforce the deny rules.
  public static void createDenyPolicy(String projectId, String policyId)
      throws IOException, ExecutionException, InterruptedException, TimeoutException {

    try (PoliciesClient policiesClient = PoliciesClient.create()) {
      // Each deny policy is attached to an organization, folder, or project.
      // To work with deny policies, specify the attachment point.
      //
      // Its format can be one of the following:
      // 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
      // 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
      // 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
      //
      // The attachment point is identified by its URL-encoded resource name.
      String urlEncodedResource =
          URLEncoder.encode(
              "cloudresourcemanager.googleapis.com/projects/", StandardCharsets.UTF_8);
      String attachmentPoint = String.format("%s%s", urlEncodedResource, projectId);

      // Construct the full path of the resource to which the policy is attached.
      // Its format is: "policies/{attachmentPoint}/denypolicies/{policyId}"
      String policyParent = String.format("policies/%s/denypolicies", attachmentPoint);

      DenyRule denyRule =
          DenyRule.newBuilder()
              // Add one or more principals who should be denied the permissions specified in this
              // rule.
              // For more information on allowed values, see:
              // https://cloud.google.com/iam/docs/principal-identifiers
              .addDeniedPrincipals("principalSet://goog/public:all")

              // Optionally, set the principals who should be exempted from the
              // list of denied principals. For example, if you want to deny certain permissions
              // to a group but exempt a few principals, then add those here.
              // .addExceptionPrincipals(
              //     "principalSet://goog/group/project-admins@example.com")

              // Set the permissions to deny.
              // The permission value is of the format: service_fqdn/resource.action
              // For the list of supported permissions, see:
              // https://cloud.google.com/iam/help/deny/supported-permissions
              .addDeniedPermissions("cloudresourcemanager.googleapis.com/projects.delete")

              // Optionally, add the permissions to be exempted from this rule.
              // Meaning, the deny rule will not be applicable to these permissions.
              // .addExceptionPermissions("cloudresourcemanager.googleapis.com/projects.create")

              // Set the condition which will enforce the deny rule. If this condition is true,
              // the deny rule will be applicable. Else, the rule will not be enforced.
              .setDenialCondition(
                  Expr.newBuilder()
                      // The expression uses Common Expression Language syntax (CEL).
                      // Here we block access based on tags.
                      //
                      // A tag is a key-value pair that can be attached to an organization, folder,
                      // or project. You can use deny policies to deny permissions based on tags
                      // without adding an IAM Condition to every role grant.
                      // For example, imagine that you tag all of your projects as dev, test, or
                      // prod. You want only members of project-admins@example.com to be able to
                      // perform operations on projects that are tagged prod.
                      // To solve this problem, you create a deny rule that denies the
                      // cloudresourcemanager.googleapis.com/projects.delete permission to everyone
                      // except project-admins@example.com for resources that are tagged test.
                      .setExpression("!resource.matchTag('12345678/env', 'test')")
                      .setTitle("Only for test projects")
                      .build())
              .build();

      // Add the deny rule and a description for it.
      Policy policy =
          Policy.newBuilder()
              // Set the deny rule.
              .addRules(
                  PolicyRule.newBuilder()
                      // Set a description for the rule.
                      .setDescription(
                          "block all principals from deleting projects, unless the principal"
                              + " is a member of project-admins@example.com and the project"
                              + " being deleted has a tag with the value test")
                      .setDenyRule(denyRule)
                      .build())
              .build();

      // Set the policy resource path, policy rules and a unique ID for the policy.
      CreatePolicyRequest createPolicyRequest =
          CreatePolicyRequest.newBuilder()
              .setParent(policyParent)
              .setPolicy(policy)
              .setPolicyId(policyId)
              .build();

      // Build the create policy request.
      Operation operation =
          policiesClient
              .createPolicyCallable()
              .futureCall(createPolicyRequest)
              .get(3, TimeUnit.MINUTES);

      // Wait for the operation to complete.
      if (operation.hasError()) {
        System.out.println("Error in creating the policy " + operation.getError());
        return;
      }

      // Retrieve the policy name.
      Policy response = policiesClient.getPolicy(String.format("%s/%s", policyParent, policyId));
      String policyName = response.getName();
      System.out.println(
          "Created the deny policy: " + policyName.substring(policyName.lastIndexOf("/") + 1));
    }
  }
}

/**
 * TODO(developer): Uncomment and replace these variables before running the sample.
 */
// const projectId = 'YOUR_PROJECT_ID';
// const policyID = 'YOUR_POLICY_ID';

const {PoliciesClient} = require('@google-cloud/iam').v2;

const iamClient = new PoliciesClient();

// Each deny policy is attached to an organization, folder, or project.
// To work with deny policies, specify the attachment point.
//
// Its format can be one of the following:
// 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
// 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
// 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
//
// The attachment point is identified by its URL-encoded resource name. Hence, replace
// the "/" with "%2F".
const attachmentPoint = `cloudresourcemanager.googleapis.com%2Fprojects%2F${projectId}`;

const denyRule = {
  // Add one or more principals who should be denied the permissions specified in this rule.
  // For more information on allowed values, see: https://cloud.google.com/iam/help/deny/principal-identifiers
  deniedPrincipals: ['principalSet://goog/public:all'],
  // Optionally, set the principals who should be exempted from the
  // list of denied principals. For example, if you want to deny certain permissions
  // to a group but exempt a few principals, then add those here.
  // exceptionPrincipals: ['principalSet://goog/group/project-admins@example.com'],
  // Set the permissions to deny.
  // The permission value is of the format: service_fqdn/resource.action
  // For the list of supported permissions, see: https://cloud.google.com/iam/help/deny/supported-permissions
  deniedPermissions: ['cloudresourcemanager.googleapis.com/projects.delete'],
  // Optionally, add the permissions to be exempted from this rule.
  // Meaning, the deny rule will not be applicable to these permissions.
  // exceptionPermissions: ['cloudresourcemanager.googleapis.com/projects.create']
  //
  // Set the condition which will enforce the deny rule.
  // If this condition is true, the deny rule will be applicable. Else, the rule will not be enforced.
  // The expression uses Common Expression Language syntax (CEL).
  // Here we block access based on tags.
  //
  // Here, we create a deny rule that denies the cloudresourcemanager.googleapis.com/projects.delete permission to everyone except project-admins@example.com for resources that are tagged test.
  // A tag is a key-value pair that can be attached to an organization, folder, or project.
  // For more info, see: https://cloud.google.com/iam/docs/deny-access#create-deny-policy
  denialCondition: {
    expression: '!resource.matchTag("12345678/env", "test")',
  },
};

async function createDenyPolicy() {
  const request = {
    parent: `policies/${attachmentPoint}/denypolicies`,
    policy: {
      displayName: 'Restrict project deletion access',
      rules: [
        {
          description:
            'block all principals from deleting projects, unless the principal is a member of project-admins@example.com and the project being deleted has a tag with the value test',
          denyRule,
        },
      ],
    },
    policyId,
  };

  const [operation] = await iamClient.createPolicy(request);
  const [policy] = await operation.promise();

  console.log(`Created the deny policy: ${policy.name}`);
}

createDenyPolicy();

def create_deny_policy(project_id: str, policy_id: str) -> None:
    """Create a deny policy.

    You can add deny policies to organizations, folders, and projects.
    Each of these resources can have up to 5 deny policies.

    Deny policies contain deny rules, which specify the following:
    1. The permissions to deny and/or exempt.
    2. The principals that are denied, or exempted from denial.
    3. An optional condition on when to enforce the deny rules.

    Params:
    project_id: ID or number of the Google Cloud project you want to use.
    policy_id: Specify the ID of the deny policy you want to create.
    """

    from google.cloud import iam_v2
    from google.cloud.iam_v2 import types

    policies_client = iam_v2.PoliciesClient()

    # Each deny policy is attached to an organization, folder, or project.
    # To work with deny policies, specify the attachment point.
    #
    # Its format can be one of the following:
    # 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
    # 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
    # 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
    #
    # The attachment point is identified by its URL-encoded resource name. Hence, replace
    # the "/" with "%2F".
    attachment_point = f"cloudresourcemanager.googleapis.com%2Fprojects%2F{project_id}"

    deny_rule = types.DenyRule()
    # Add one or more principals who should be denied the permissions specified in this rule.
    # For more information on allowed values, see: https://cloud.google.com/iam/help/deny/principal-identifiers
    deny_rule.denied_principals = ["principalSet://goog/public:all"]

    # Optionally, set the principals who should be exempted from the
    # list of denied principals. For example, if you want to deny certain permissions
    # to a group but exempt a few principals, then add those here.
    # deny_rule.exception_principals = ["principalSet://goog/group/project-admins@example.com"]

    # Set the permissions to deny.
    # The permission value is of the format: service_fqdn/resource.action
    # For the list of supported permissions, see: https://cloud.google.com/iam/help/deny/supported-permissions
    deny_rule.denied_permissions = [
        "cloudresourcemanager.googleapis.com/projects.delete"
    ]

    # Optionally, add the permissions to be exempted from this rule.
    # Meaning, the deny rule will not be applicable to these permissions.
    # deny_rule.exception_permissions = ["cloudresourcemanager.googleapis.com/projects.create"]

    # Set the condition which will enforce the deny rule.
    # If this condition is true, the deny rule will be applicable. Else, the rule will not be enforced.
    # The expression uses Common Expression Language syntax (CEL).
    # Here we block access based on tags.
    #
    # Here, we create a deny rule that denies the cloudresourcemanager.googleapis.com/projects.delete permission to everyone except project-admins@example.com for resources that are tagged test.
    # A tag is a key-value pair that can be attached to an organization, folder, or project.
    # For more info, see: https://cloud.google.com/iam/docs/deny-access#create-deny-policy
    deny_rule.denial_condition = {
        "expression": "!resource.matchTag('12345678/env', 'test')"
    }

    # Add the deny rule and a description for it.
    policy_rule = types.PolicyRule()
    policy_rule.description = "block all principals from deleting projects, unless the principal is a member of project-admins@example.com and the project being deleted has a tag with the value test"
    policy_rule.deny_rule = deny_rule

    policy = types.Policy()
    policy.display_name = "Restrict project deletion access"
    policy.rules = [policy_rule]

    # Set the policy resource path, policy rules and a unique ID for the policy.
    request = types.CreatePolicyRequest()
    # Construct the full path of the resource's deny policies.
    # Its format is: "policies/{attachmentPoint}/denypolicies"
    request.parent = f"policies/{attachment_point}/denypolicies"
    request.policy = policy
    request.policy_id = policy_id

    # Build the create policy request and wait for the operation to complete.
    result = policies_client.create_policy(request=request).result()
    print(f"Created the deny policy: {result.name.rsplit('/')[-1]}")


if __name__ == "__main__":
    import uuid

    # Your Google Cloud project ID.
    PROJECT_ID = os.getenv("GOOGLE_CLOUD_PROJECT", "your-google-cloud-project-id")

    # Any unique ID (0 to 63 chars) starting with a lowercase letter.
    policy_id = f"deny-{uuid.uuid4()}"

    # Test the policy lifecycle.
    create_deny_policy(PROJECT_ID, policy_id)

import (
	"context"
	"fmt"
	"io"

	iam "cloud.google.com/go/iam/apiv2"
	"cloud.google.com/go/iam/apiv2/iampb"
	"google.golang.org/api/iterator"
)

// listDenyPolicies lists all the deny policies that are attached to a resource.
// A resource can have up to 5 deny policies.
func listDenyPolicies(w io.Writer, projectID string) error {
	// projectID := "your_project_id"

	ctx := context.Background()
	policiesClient, err := iam.NewPoliciesClient(ctx)
	if err != nil {
		return fmt.Errorf("NewPoliciesClient: %w", err)
	}
	defer policiesClient.Close()

	// Each deny policy is attached to an organization, folder, or project.
	// To work with deny policies, specify the attachment point.
	//
	// Its format can be one of the following:
	// 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
	// 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
	// 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
	//
	// The attachment point is identified by its URL-encoded resource name. Hence, replace
	// the "/" with "%%2F".
	attachmentPoint := fmt.Sprintf(
		"cloudresourcemanager.googleapis.com%%2Fprojects%%2F%s",
		projectID,
	)

	req := &iampb.ListPoliciesRequest{
		// Construct the full path of the resource's deny policies.
		// Its format is: "policies/ATTACHMENT_POINT/denypolicies"
		Parent: fmt.Sprintf("policies/%s/denypolicies", attachmentPoint),
	}
	it := policiesClient.ListPolicies(ctx, req)
	fmt.Fprintf(w, "Policies found in project %s:\n", projectID)

	for {
		policy, err := it.Next()
		if err == iterator.Done {
			break
		}
		if err != nil {
			return err
		}
		fmt.Fprintf(w, "- %s\n", policy.GetName())
	}
	return nil
}

import com.google.iam.v2.PoliciesClient;
import com.google.iam.v2.Policy;
import java.io.IOException;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;

public class ListDenyPolicies {

  public static void main(String[] args) throws IOException {
    // TODO(developer): Replace these variables before running the sample.
    // ID or number of the Google Cloud project you want to use.
    String projectId = "your-google-cloud-project-id";

    listDenyPolicies(projectId);
  }

  // List all the deny policies that are attached to a resource.
  // A resource can have up to 5 deny policies.
  public static void listDenyPolicies(String projectId) throws IOException {
    // Initialize the Policies client.
    try (PoliciesClient policiesClient = PoliciesClient.create()) {

      // Each deny policy is attached to an organization, folder, or project.
      // To work with deny policies, specify the attachment point.
      //
      // Its format can be one of the following:
      // 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
      // 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
      // 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
      //
      // The attachment point is identified by its URL-encoded resource name.
      String urlEncodedResource =
          URLEncoder.encode(
              "cloudresourcemanager.googleapis.com/projects/", StandardCharsets.UTF_8);
      String attachmentPoint = String.format("%s%s", urlEncodedResource, projectId);

      // Construct the full path of the resource to which the policy is attached.
      // Its format is: "policies/{attachmentPoint}/denypolicies"
      String policyParent = String.format("policies/%s/denypolicies", attachmentPoint);

      // Create a list request and iterate over the returned policies.
      for (Policy policy : policiesClient.listPolicies(policyParent).iterateAll()) {
        System.out.println(policy.getName());
      }
      System.out.println("Listed all deny policies");
    }
  }
}

/**
 * TODO(developer): Uncomment and replace these variables before running the sample.
 */
// const projectId = 'YOUR_PROJECT_ID';

const {PoliciesClient} = require('@google-cloud/iam').v2;

const iamClient = new PoliciesClient();

// Each deny policy is attached to an organization, folder, or project.
// To work with deny policies, specify the attachment point.
//
// Its format can be one of the following:
// 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
// 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
// 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
//
// The attachment point is identified by its URL-encoded resource name. Hence, replace
// the "/" with "%2F".
const attachmentPoint = `cloudresourcemanager.googleapis.com%2Fprojects%2F${projectId}`;

async function listDenyPolicies() {
  const request = {
    parent: `policies/${attachmentPoint}/denypolicies`,
  };

  const policies = await iamClient.listPoliciesAsync(request);
  for await (const policy of policies) {
    console.log(`- ${policy.name}`);
  }
}

listDenyPolicies();

def list_deny_policy(project_id: str) -> None:
    """List all the deny policies that are attached to a resource.

    A resource can have up to 5 deny policies.

    project_id: ID or number of the Google Cloud project you want to use.
    """

    from google.cloud import iam_v2
    from google.cloud.iam_v2 import types

    policies_client = iam_v2.PoliciesClient()

    # Each deny policy is attached to an organization, folder, or project.
    # To work with deny policies, specify the attachment point.
    #
    # Its format can be one of the following:
    # 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
    # 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
    # 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
    #
    # The attachment point is identified by its URL-encoded resource name. Hence, replace
    # the "/" with "%2F".
    attachment_point = f"cloudresourcemanager.googleapis.com%2Fprojects%2F{project_id}"

    request = types.ListPoliciesRequest()
    # Construct the full path of the resource's deny policies.
    # Its format is: "policies/{attachmentPoint}/denypolicies"
    request.parent = f"policies/{attachment_point}/denypolicies"

    # Create a list request and iterate over the returned policies.
    policies = policies_client.list_policies(request=request)

    for policy in policies:
        print(policy.name)
    print("Listed all deny policies")


if __name__ == "__main__":
    # Your Google Cloud project ID.
    PROJECT_ID = os.getenv("GOOGLE_CLOUD_PROJECT", "your-google-cloud-project-id")

    # Any unique ID (0 to 63 chars) starting with a lowercase letter.
    policy_id = f"deny-{uuid.uuid4()}"

    list_deny_policy(PROJECT_ID)

import (
	"context"
	"fmt"
	"io"

	iam "cloud.google.com/go/iam/apiv2"
	"cloud.google.com/go/iam/apiv2/iampb"
)

// getDenyPolicy retrieves the deny policy given the project ID and policy ID.
func getDenyPolicy(w io.Writer, projectID, policyID string) error {
	// projectID := "your_project_id"
	// policyID := "your_policy_id"

	ctx := context.Background()
	policiesClient, err := iam.NewPoliciesClient(ctx)
	if err != nil {
		return fmt.Errorf("NewPoliciesClient: %w", err)
	}
	defer policiesClient.Close()

	// Each deny policy is attached to an organization, folder, or project.
	// To work with deny policies, specify the attachment point.
	//
	// Its format can be one of the following:
	// 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
	// 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
	// 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
	//
	// The attachment point is identified by its URL-encoded resource name. Hence, replace
	// the "/" with "%%2F".
	attachmentPoint := fmt.Sprintf(
		"cloudresourcemanager.googleapis.com%%2Fprojects%%2F%s",
		projectID,
	)

	req := &iampb.GetPolicyRequest{
		// Construct the full path of the policy.
		// Its format is: "policies/ATTACHMENT_POINT/denypolicies/POLICY_ID"
		Name: fmt.Sprintf("policies/%s/denypolicies/%s", attachmentPoint, policyID),
	}
	policy, err := policiesClient.GetPolicy(ctx, req)
	if err != nil {
		return fmt.Errorf("unable to get policy: %w", err)
	}

	fmt.Fprintf(w, "Policy %s retrieved\n", policy.GetName())

	return nil
}

import com.google.iam.v2.GetPolicyRequest;
import com.google.iam.v2.PoliciesClient;
import com.google.iam.v2.Policy;
import java.io.IOException;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;

public class GetDenyPolicy {

  public static void main(String[] args) throws IOException {
    // TODO(developer): Replace these variables before running the sample.

    // ID or number of the Google Cloud project you want to use.
    String projectId = "your-google-cloud-project-id";

    // Specify the ID of the deny policy you want to retrieve.
    String policyId = "deny-policy-id";

    getDenyPolicy(projectId, policyId);
  }

  // Retrieve the deny policy given the project ID and policy ID.
  public static void getDenyPolicy(String projectId, String policyId) throws IOException {
    // Create the IAM Policies client.
    try (PoliciesClient policiesClient = PoliciesClient.create()) {

      // Each deny policy is attached to an organization, folder, or project.
      // To work with deny policies, specify the attachment point.
      //
      // Its format can be one of the following:
      // 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
      // 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
      // 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
      //
      // The attachment point is identified by its URL-encoded resource name.
      String urlEncodedResource =
          URLEncoder.encode(
              "cloudresourcemanager.googleapis.com/projects/", StandardCharsets.UTF_8);
      String attachmentPoint = String.format("%s%s", urlEncodedResource, projectId);

      // Construct the full path of the resource to which the policy is attached.
      // Its format is: "policies/{attachmentPoint}/denypolicies/{policyId}"
      String policyParent = String.format("policies/%s/denypolicies/%s", attachmentPoint, policyId);

      // Specify the policyParent and execute the GetPolicy request.
      GetPolicyRequest getPolicyRequest =
          GetPolicyRequest.newBuilder().setName(policyParent).build();

      Policy policy = policiesClient.getPolicy(getPolicyRequest);
      System.out.printf("Retrieved the deny policy: %s : %s%n", policyId, policy);
    }
  }
}

/**
 * TODO(developer): Uncomment and replace these variables before running the sample.
 */
// const projectId = 'YOUR_PROJECT_ID';
// const policyID = 'YOUR_POLICY_ID';

const {PoliciesClient} = require('@google-cloud/iam').v2;

const iamClient = new PoliciesClient();

// Each deny policy is attached to an organization, folder, or project.
// To work with deny policies, specify the attachment point.
//
// Its format can be one of the following:
// 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
// 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
// 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
//
// The attachment point is identified by its URL-encoded resource name. Hence, replace
// the "/" with "%2F".
const attachmentPoint = `cloudresourcemanager.googleapis.com%2Fprojects%2F${projectId}`;

async function getDenyPolicy() {
  const request = {
    name: `policies/${attachmentPoint}/denypolicies/${policyId}`,
  };

  const [policy] = await iamClient.getPolicy(request);

  console.log(`Retrieved the deny policy: ${policy.name}`);
}

getDenyPolicy();

from google.cloud import iam_v2
from google.cloud.iam_v2 import Policy, types


def get_deny_policy(project_id: str, policy_id: str) -> Policy:
    """Retrieve the deny policy given the project ID and policy ID.

    project_id: ID or number of the Google Cloud project you want to use.
    policy_id: The ID of the deny policy you want to retrieve.
    """
    policies_client = iam_v2.PoliciesClient()

    # Each deny policy is attached to an organization, folder, or project.
    # To work with deny policies, specify the attachment point.
    #
    # Its format can be one of the following:
    # 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
    # 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
    # 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
    #
    # The attachment point is identified by its URL-encoded resource name. Hence, replace
    # the "/" with "%2F".
    attachment_point = f"cloudresourcemanager.googleapis.com%2Fprojects%2F{project_id}"

    request = types.GetPolicyRequest()
    # Construct the full path of the policy.
    # Its format is: "policies/{attachmentPoint}/denypolicies/{policyId}"
    request.name = f"policies/{attachment_point}/denypolicies/{policy_id}"

    # Execute the GetPolicy request.
    policy = policies_client.get_policy(request=request)
    print(f"Retrieved the deny policy: {policy_id} : {policy}")
    return policy


if __name__ == "__main__":
    # Your Google Cloud project ID.
    PROJECT_ID = os.getenv("GOOGLE_CLOUD_PROJECT", "your-google-cloud-project-id")

    # Any unique ID (0 to 63 chars) starting with a lowercase letter.
    policy_id = f"deny-{uuid.uuid4()}"

    policy = get_deny_policy(PROJECT_ID, policy_id)

import (
	"context"
	"fmt"
	"io"

	iam "cloud.google.com/go/iam/apiv2"
	"cloud.google.com/go/iam/apiv2/iampb"
)

// getDenyPolicy retrieves the deny policy given the project ID and policy ID.
func getDenyPolicy(w io.Writer, projectID, policyID string) error {
	// projectID := "your_project_id"
	// policyID := "your_policy_id"

	ctx := context.Background()
	policiesClient, err := iam.NewPoliciesClient(ctx)
	if err != nil {
		return fmt.Errorf("NewPoliciesClient: %w", err)
	}
	defer policiesClient.Close()

	// Each deny policy is attached to an organization, folder, or project.
	// To work with deny policies, specify the attachment point.
	//
	// Its format can be one of the following:
	// 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
	// 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
	// 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
	//
	// The attachment point is identified by its URL-encoded resource name. Hence, replace
	// the "/" with "%%2F".
	attachmentPoint := fmt.Sprintf(
		"cloudresourcemanager.googleapis.com%%2Fprojects%%2F%s",
		projectID,
	)

	req := &iampb.GetPolicyRequest{
		// Construct the full path of the policy.
		// Its format is: "policies/ATTACHMENT_POINT/denypolicies/POLICY_ID"
		Name: fmt.Sprintf("policies/%s/denypolicies/%s", attachmentPoint, policyID),
	}
	policy, err := policiesClient.GetPolicy(ctx, req)
	if err != nil {
		return fmt.Errorf("unable to get policy: %w", err)
	}

	fmt.Fprintf(w, "Policy %s retrieved\n", policy.GetName())

	return nil
}

import com.google.iam.v2.GetPolicyRequest;
import com.google.iam.v2.PoliciesClient;
import com.google.iam.v2.Policy;
import java.io.IOException;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;

public class GetDenyPolicy {

  public static void main(String[] args) throws IOException {
    // TODO(developer): Replace these variables before running the sample.

    // ID or number of the Google Cloud project you want to use.
    String projectId = "your-google-cloud-project-id";

    // Specify the ID of the deny policy you want to retrieve.
    String policyId = "deny-policy-id";

    getDenyPolicy(projectId, policyId);
  }

  // Retrieve the deny policy given the project ID and policy ID.
  public static void getDenyPolicy(String projectId, String policyId) throws IOException {
    // Create the IAM Policies client.
    try (PoliciesClient policiesClient = PoliciesClient.create()) {

      // Each deny policy is attached to an organization, folder, or project.
      // To work with deny policies, specify the attachment point.
      //
      // Its format can be one of the following:
      // 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
      // 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
      // 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
      //
      // The attachment point is identified by its URL-encoded resource name.
      String urlEncodedResource =
          URLEncoder.encode(
              "cloudresourcemanager.googleapis.com/projects/", StandardCharsets.UTF_8);
      String attachmentPoint = String.format("%s%s", urlEncodedResource, projectId);

      // Construct the full path of the resource to which the policy is attached.
      // Its format is: "policies/{attachmentPoint}/denypolicies/{policyId}"
      String policyParent = String.format("policies/%s/denypolicies/%s", attachmentPoint, policyId);

      // Specify the policyParent and execute the GetPolicy request.
      GetPolicyRequest getPolicyRequest =
          GetPolicyRequest.newBuilder().setName(policyParent).build();

      Policy policy = policiesClient.getPolicy(getPolicyRequest);
      System.out.printf("Retrieved the deny policy: %s : %s%n", policyId, policy);
    }
  }
}

/**
 * TODO(developer): Uncomment and replace these variables before running the sample.
 */
// const projectId = 'YOUR_PROJECT_ID';
// const policyID = 'YOUR_POLICY_ID';

const {PoliciesClient} = require('@google-cloud/iam').v2;

const iamClient = new PoliciesClient();

// Each deny policy is attached to an organization, folder, or project.
// To work with deny policies, specify the attachment point.
//
// Its format can be one of the following:
// 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
// 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
// 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
//
// The attachment point is identified by its URL-encoded resource name. Hence, replace
// the "/" with "%2F".
const attachmentPoint = `cloudresourcemanager.googleapis.com%2Fprojects%2F${projectId}`;

async function getDenyPolicy() {
  const request = {
    name: `policies/${attachmentPoint}/denypolicies/${policyId}`,
  };

  const [policy] = await iamClient.getPolicy(request);

  console.log(`Retrieved the deny policy: ${policy.name}`);
}

getDenyPolicy();

from google.cloud import iam_v2
from google.cloud.iam_v2 import Policy, types


def get_deny_policy(project_id: str, policy_id: str) -> Policy:
    """Retrieve the deny policy given the project ID and policy ID.

    project_id: ID or number of the Google Cloud project you want to use.
    policy_id: The ID of the deny policy you want to retrieve.
    """
    policies_client = iam_v2.PoliciesClient()

    # Each deny policy is attached to an organization, folder, or project.
    # To work with deny policies, specify the attachment point.
    #
    # Its format can be one of the following:
    # 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
    # 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
    # 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
    #
    # The attachment point is identified by its URL-encoded resource name. Hence, replace
    # the "/" with "%2F".
    attachment_point = f"cloudresourcemanager.googleapis.com%2Fprojects%2F{project_id}"

    request = types.GetPolicyRequest()
    # Construct the full path of the policy.
    # Its format is: "policies/{attachmentPoint}/denypolicies/{policyId}"
    request.name = f"policies/{attachment_point}/denypolicies/{policy_id}"

    # Execute the GetPolicy request.
    policy = policies_client.get_policy(request=request)
    print(f"Retrieved the deny policy: {policy_id} : {policy}")
    return policy


if __name__ == "__main__":
    # Your Google Cloud project ID.
    PROJECT_ID = os.getenv("GOOGLE_CLOUD_PROJECT", "your-google-cloud-project-id")

    # Any unique ID (0 to 63 chars) starting with a lowercase letter.
    policy_id = f"deny-{uuid.uuid4()}"

    policy = get_deny_policy(PROJECT_ID, policy_id)

import (
	"context"
	"fmt"
	"io"

	iam "cloud.google.com/go/iam/apiv2"

	"cloud.google.com/go/iam/apiv2/iampb"
	"google.golang.org/genproto/googleapis/type/expr"
)

// updateDenyPolicy updates the deny rules and/ or its display name after policy creation.
func updateDenyPolicy(w io.Writer, projectID, policyID, etag string) error {
	// projectID := "your_project_id"
	// policyID := "your_policy_id"
	// etag := "your_etag"

	ctx := context.Background()
	policiesClient, err := iam.NewPoliciesClient(ctx)
	if err != nil {
		return fmt.Errorf("NewPoliciesClient: %w", err)
	}
	defer policiesClient.Close()

	// Each deny policy is attached to an organization, folder, or project.
	// To work with deny policies, specify the attachment point.
	//
	// Its format can be one of the following:
	// 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
	// 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
	// 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
	//
	// The attachment point is identified by its URL-encoded resource name. Hence, replace
	// the "/" with "%%2F".
	attachmentPoint := fmt.Sprintf(
		"cloudresourcemanager.googleapis.com%%2Fprojects%%2F%s",
		projectID,
	)

	denyRule := &iampb.DenyRule{
		// Add one or more principals who should be denied the permissions specified in this rule.
		// For more information on allowed values,
		// see: https://cloud.google.com/iam/help/deny/principal-identifiers
		DeniedPrincipals: []string{"principalSet://goog/public:all"},
		// Optionally, set the principals who should be exempted from the
		// list of denied principals. For example, if you want to deny certain permissions
		// to a group but exempt a few principals, then add those here.
		// ExceptionPrincipals: []string{"principalSet://goog/group/project-admins@example.com"},
		//
		// Set the permissions to deny.
		// The permission value is of the format: service_fqdn/resource.action
		// For the list of supported permissions,
		// see: https://cloud.google.com/iam/help/deny/supported-permissions
		DeniedPermissions: []string{"cloudresourcemanager.googleapis.com/projects.delete"},
		// Optionally, add the permissions to be exempted from this rule.
		// Meaning, the deny rule will not be applicable to these permissions.
		// ExceptionPermissions: []string{"cloudresourcemanager.googleapis.com/projects.create"},
		//
		// Set the condition which will enforce the deny rule.
		// If this condition is true, the deny rule will be applicable.
		// Else, the rule will not be enforced.
		// The expression uses Common Expression Language syntax (CEL).
		// Here we block access based on tags.
		//
		// Here, we create a deny rule that denies the
		// cloudresourcemanager.googleapis.com/projects.delete permission
		// to everyone except project-admins@example.com for resources that are tagged prod.
		// A tag is a key-value pair that can be attached to an organization, folder, or project.
		// For more info, see: https://cloud.google.com/iam/docs/deny-access#create-deny-policy
		DenialCondition: &expr.Expr{
			Expression: "!resource.matchTag('12345678/env', 'prod')",
		},
	}

	// Set the rule description and deny rule to update.
	policyRule := &iampb.PolicyRule{
		Description: "block all principals from deleting projects, unless the principal is a member of project-admins@example.com and the project being deleted has a tag with the value prod",
		Kind: &iampb.PolicyRule_DenyRule{
			DenyRule: denyRule,
		},
	}

	// Set the policy resource path, version (etag) and the updated deny rules.
	policy := &iampb.Policy{
		// Construct the full path of the policy.
		// Its format is: "policies/ATTACHMENT_POINT/denypolicies/POLICY_ID"
		Name:  fmt.Sprintf("policies/%s/denypolicies/%s", attachmentPoint, policyID),
		Etag:  etag,
		Rules: [](*iampb.PolicyRule){policyRule},
	}

	// Create the update policy request.
	req := &iampb.UpdatePolicyRequest{
		Policy: policy,
	}
	op, err := policiesClient.UpdatePolicy(ctx, req)
	if err != nil {
		return fmt.Errorf("unable to update policy: %w", err)
	}

	policy, err = op.Wait(ctx)
	if err != nil {
		return fmt.Errorf("unable to wait for the operation: %w", err)
	}

	fmt.Fprintf(w, "Policy %s updated\n", policy.GetName())

	return nil
}

import com.google.iam.v2.DenyRule;
import com.google.iam.v2.PoliciesClient;
import com.google.iam.v2.Policy;
import com.google.iam.v2.PolicyRule;
import com.google.iam.v2.UpdatePolicyRequest;
import com.google.longrunning.Operation;
import com.google.type.Expr;
import java.io.IOException;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

public class UpdateDenyPolicy {

  public static void main(String[] args)
      throws IOException, ExecutionException, InterruptedException, TimeoutException {
    // TODO(developer): Replace these variables before running the sample.

    // ID or number of the Google Cloud project you want to use.
    String projectId = "your-google-cloud-project-id";

    // Specify the ID of the Deny policy you want to retrieve.
    String policyId = "deny-policy-id";

    // Etag field that identifies the policy version. The etag changes each time
    // you update the policy. Get the etag of an existing policy by performing a GetPolicy request.
    String etag = "policy_etag";

    updateDenyPolicy(projectId, policyId, etag);
  }

  // Update the deny rules and/ or its display name after policy creation.
  public static void updateDenyPolicy(String projectId, String policyId, String etag)
      throws IOException, ExecutionException, InterruptedException, TimeoutException {

    try (PoliciesClient policiesClient = PoliciesClient.create()) {

      // Each deny policy is attached to an organization, folder, or project.
      // To work with deny policies, specify the attachment point.
      //
      // Its format can be one of the following:
      // 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
      // 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
      // 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
      //
      // The attachment point is identified by its URL-encoded resource name.
      String urlEncodedResource =
          URLEncoder.encode(
              "cloudresourcemanager.googleapis.com/projects/", StandardCharsets.UTF_8);
      String attachmentPoint = String.format("%s%s", urlEncodedResource, projectId);

      // Construct the full path of the resource to which the policy is attached to.
      // Its format is: "policies/{attachmentPoint}/denypolicies/{policyId}"
      String policyParent = String.format("policies/%s/denypolicies/%s", attachmentPoint, policyId);

      DenyRule denyRule =
          DenyRule.newBuilder()
              // Add one or more principals who should be denied the permissions specified in this
              // rule.
              // For more information on allowed values, see:
              // https://cloud.google.com/iam/docs/principal-identifiers
              .addDeniedPrincipals("principalSet://goog/public:all")

              // Optionally, set the principals who should be exempted from the list of principals
              // added in "DeniedPrincipals".
              // Example, if you want to deny certain permissions to a group but exempt a few
              // principals, then add those here.
              // .addExceptionPrincipals(
              //     "principalSet://goog/group/project-admins@example.com")

              // Set the permissions to deny.
              // The permission value is of the format: service_fqdn/resource.action
              // For the list of supported permissions, see:
              // https://cloud.google.com/iam/help/deny/supported-permissions
              .addDeniedPermissions("cloudresourcemanager.googleapis.com/projects.delete")

              // Add the permissions to be exempted from this rule.
              // Meaning, the deny rule will not be applicable to these permissions.
              // .addExceptionPermissions("cloudresourcemanager.googleapis.com/projects.get")

              // Set the condition which will enforce the deny rule.
              // If this condition is true, the deny rule will be applicable. Else, the rule will
              // not be enforced.
              .setDenialCondition(
                  Expr.newBuilder()
                      // The expression uses Common Expression Language syntax (CEL). Here we block
                      // access based on tags.
                      //
                      // A tag is a key-value pair that can be attached to an organization, folder,
                      // or project. You can use deny policies to deny permissions based on tags
                      // without adding an IAM Condition to every role grant.
                      // For example, imagine that you tag all of your projects as dev, test, or
                      // prod. You want only members of project-admins@example.com to be able to
                      // perform operations on projects that are tagged prod.
                      // To solve this problem, you create a deny rule that denies the
                      // cloudresourcemanager.googleapis.com/projects.delete permission to everyone
                      // except project-admins@example.com for resources that are tagged prod.
                      .setExpression("!resource.matchTag('12345678/env', 'prod')")
                      .setTitle("Only for prod projects")
                      .build())
              .build();

      // Set the policy resource path, version (etag) and the updated deny rules.
      Policy policy =
          Policy.newBuilder()
              .setName(policyParent)
              .setEtag(etag)
              .addRules(
                  PolicyRule.newBuilder()
                      // Set the rule description to update.
                      .setDescription(
                          "Block all principals from deleting projects, unless the principal"
                              + " is a member of project-admins@example.com and the project"
                              + "being deleted has a tag with the value prod")
                      // Set the deny rule to update.
                      .setDenyRule(denyRule)
                      .build())
              .build();

      // Create the update policy request.
      UpdatePolicyRequest updatePolicyRequest =
          UpdatePolicyRequest.newBuilder().setPolicy(policy).build();

      // Wait for the operation to complete.
      Operation operation =
          policiesClient
              .updatePolicyCallable()
              .futureCall(updatePolicyRequest)
              .get(3, TimeUnit.MINUTES);

      if (operation.hasError()) {
        System.out.println("Error in updating the policy " + operation.getError());
        return;
      }

      System.out.println("Updated the deny policy: " + policyId);
    }
  }
}

/**
 * TODO(developer): Uncomment and replace these variables before running the sample.
 */
// const projectId = 'YOUR_PROJECT_ID';
// const policyID = 'YOUR_POLICY_ID';
// const etag = 'YOUR_ETAG';

const {PoliciesClient} = require('@google-cloud/iam').v2;

const iamClient = new PoliciesClient();

// Each deny policy is attached to an organization, folder, or project.
// To work with deny policies, specify the attachment point.
//
// Its format can be one of the following:
// 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
// 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
// 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
//
// The attachment point is identified by its URL-encoded resource name. Hence, replace
// the "/" with "%2F".
const attachmentPoint = `cloudresourcemanager.googleapis.com%2Fprojects%2F${projectId}`;

const denyRule = {
  // Add one or more principals who should be denied the permissions specified in this rule.
  // For more information on allowed values, see: https://cloud.google.com/iam/help/deny/principal-identifiers
  deniedPrincipals: ['principalSet://goog/public:all'],
  // Optionally, set the principals who should be exempted from the
  // list of denied principals. For example, if you want to deny certain permissions
  // to a group but exempt a few principals, then add those here.
  // exceptionPrincipals: ['principalSet://goog/group/project-admins@example.com'],
  // Set the permissions to deny.
  // The permission value is of the format: service_fqdn/resource.action
  // For the list of supported permissions, see: https://cloud.google.com/iam/help/deny/supported-permissions
  deniedPermissions: ['cloudresourcemanager.googleapis.com/projects.delete'],
  // Optionally, add the permissions to be exempted from this rule.
  // Meaning, the deny rule will not be applicable to these permissions.
  // exceptionPermissions: ['cloudresourcemanager.googleapis.com/projects.create']
  //
  // Set the condition which will enforce the deny rule.
  // If this condition is true, the deny rule will be applicable. Else, the rule will not be enforced.
  // The expression uses Common Expression Language syntax (CEL).
  // Here we block access based on tags.
  //
  // Here, we create a deny rule that denies the cloudresourcemanager.googleapis.com/projects.delete permission to everyone except project-admins@example.com for resources that are tagged test.
  // A tag is a key-value pair that can be attached to an organization, folder, or project.
  // For more info, see: https://cloud.google.com/iam/docs/deny-access#create-deny-policy
  denialCondition: {
    expression: '!resource.matchTag("12345678/env", "prod")',
  },
};

async function updateDenyPolicy() {
  const request = {
    policy: {
      name: `policies/${attachmentPoint}/denypolicies/${policyId}`,
      etag,
      rules: [
        {
          description:
            'block all principals from deleting projects, unless the principal is a member of project-admins@example.com and the project being deleted has a tag with the value prod',
          denyRule,
        },
      ],
    },
    policyId,
  };

  const [operation] = await iamClient.updatePolicy(request);
  const [policy] = await operation.promise();

  console.log(`Updated the deny policy: ${policy.name}`);
}

updateDenyPolicy();

def update_deny_policy(project_id: str, policy_id: str, etag: str) -> None:
    """Update the deny rules and/ or its display name after policy creation.

    project_id: ID or number of the Google Cloud project you want to use.

    policy_id: The ID of the deny policy you want to retrieve.

    etag: Etag field that identifies the policy version. The etag changes each time
    you update the policy. Get the etag of an existing policy by performing a GetPolicy request.
    """

    from google.cloud import iam_v2
    from google.cloud.iam_v2 import types

    policies_client = iam_v2.PoliciesClient()

    # Each deny policy is attached to an organization, folder, or project.
    # To work with deny policies, specify the attachment point.
    #
    # Its format can be one of the following:
    # 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
    # 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
    # 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
    #
    # The attachment point is identified by its URL-encoded resource name.
    # Hence, replace the "/" with "%2F".
    attachment_point = f"cloudresourcemanager.googleapis.com%2Fprojects%2F{project_id}"

    deny_rule = types.DenyRule()

    # Add one or more principals who should be denied the permissions
    # specified in this rule.
    # For more information on allowed values, see:
    # https://cloud.google.com/iam/help/deny/principal-identifiers
    deny_rule.denied_principals = ["principalSet://goog/public:all"]

    # Optionally, set the principals who should be exempted
    # from the list of principals added in "DeniedPrincipals".
    # Example, if you want to deny certain permissions to a group
    # but exempt a few principals, then add those here.
    # deny_rule.exception_principals = ["principalSet://goog/group/project-admins@example.com"]

    # Set the permissions to deny.
    # The permission value is of the format: service_fqdn/resource.action
    # For the list of supported permissions, see:
    # https://cloud.google.com/iam/help/deny/supported-permissions
    deny_rule.denied_permissions = [
        "cloudresourcemanager.googleapis.com/projects.delete"
    ]

    # Add the permissions to be exempted from this rule.
    # Meaning, the deny rule will not be applicable to these permissions.
    # deny_rule.exception_permissions = ["cloudresourcemanager.googleapis.com/projects.get"]

    # Set the condition which will enforce the deny rule.
    # If this condition is true, the deny rule will be applicable.
    # Else, the rule will not be enforced.
    #
    # The expression uses Common Expression Language syntax (CEL).
    # Here we block access based on tags.
    #
    # Here, we create a deny rule that denies the
    # cloudresourcemanager.googleapis.com/projects.delete permission to everyone
    # except project-admins@example.com for resources that are tagged prod.
    # A tag is a key-value pair that can be attached
    # to an organization, folder, or project.
    # For more info, see:
    # https://cloud.google.com/iam/docs/deny-access#create-deny-policy
    deny_rule.denial_condition = {
        "expression": "!resource.matchTag('12345678/env', 'prod')"
    }

    # Set the rule description and deny rule to update.
    policy_rule = types.PolicyRule()
    policy_rule.description = "block all principals from deleting projects, unless the principal is a member of project-admins@example.com and the project being deleted has a tag with the value prod"
    policy_rule.deny_rule = deny_rule

    # Set the policy resource path, version (etag) and the updated deny rules.
    policy = types.Policy()
    # Construct the full path of the policy.
    # Its format is: "policies/{attachmentPoint}/denypolicies/{policyId}"
    policy.name = f"policies/{attachment_point}/denypolicies/{policy_id}"
    policy.etag = etag
    policy.rules = [policy_rule]

    # Create the update policy request.
    request = types.UpdatePolicyRequest()
    request.policy = policy

    result = policies_client.update_policy(request=request).result()
    print(f"Updated the deny policy: {result.name.rsplit('/')[-1]}")


if __name__ == "__main__":
    # Your Google Cloud project ID.
    PROJECT_ID = os.getenv("GOOGLE_CLOUD_PROJECT", "your-google-cloud-project-id")

    # Any unique ID (0 to 63 chars) starting with a lowercase letter.
    policy_id = f"deny-{uuid.uuid4()}"
    # Get the etag by performing a Get policy request.
    etag = "etag"

    update_deny_policy(PROJECT_ID, policy_id, etag)

import (
	"context"
	"fmt"
	"io"

	iam "cloud.google.com/go/iam/apiv2"

	"cloud.google.com/go/iam/apiv2/iampb"
)

// deleteDenyPolicy deletes the policy if you no longer want to enforce the rules in a deny policy.
func deleteDenyPolicy(w io.Writer, projectID, policyID string) error {
	// projectID := "your_project_id"
	// policyID := "your_policy_id"

	ctx := context.Background()
	policiesClient, err := iam.NewPoliciesClient(ctx)
	if err != nil {
		return fmt.Errorf("NewPoliciesClient: %w", err)
	}
	defer policiesClient.Close()

	// Each deny policy is attached to an organization, folder, or project.
	// To work with deny policies, specify the attachment point.
	//
	// Its format can be one of the following:
	// 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
	// 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
	// 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
	//
	// The attachment point is identified by its URL-encoded resource name. Hence, replace
	// the "/" with "%%2F".
	attachmentPoint := fmt.Sprintf(
		"cloudresourcemanager.googleapis.com%%2Fprojects%%2F%s",
		projectID,
	)

	req := &iampb.DeletePolicyRequest{
		// Construct the full path of the policy.
		// Its format is: "policies/ATTACHMENT_POINT/denypolicies/POLICY_ID"
		Name: fmt.Sprintf("policies/%s/denypolicies/%s", attachmentPoint, policyID),
	}
	op, err := policiesClient.DeletePolicy(ctx, req)
	if err != nil {
		return fmt.Errorf("unable to delete policy: %w", err)
	}

	policy, err := op.Wait(ctx)
	if err != nil {
		return fmt.Errorf("unable to wait for the operation: %w", err)
	}

	fmt.Fprintf(w, "Policy %s deleted\n", policy.GetName())

	return nil
}

import com.google.iam.v2.DeletePolicyRequest;
import com.google.iam.v2.PoliciesClient;
import com.google.longrunning.Operation;
import java.io.IOException;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

public class DeleteDenyPolicy {

  public static void main(String[] args)
      throws IOException, InterruptedException, ExecutionException, TimeoutException {
    // TODO(developer): Replace these variables before running the sample.

    // ID or number of the Google Cloud project you want to use.
    String projectId = "your-google-cloud-project-id";

    // Specify the ID of the deny policy you want to retrieve.
    String policyId = "deny-policy-id";

    deleteDenyPolicy(projectId, policyId);
  }

  // Delete the policy if you no longer want to enforce the rules in a deny policy.
  public static void deleteDenyPolicy(String projectId, String policyId)
      throws IOException, InterruptedException, ExecutionException, TimeoutException {
    try (PoliciesClient policiesClient = PoliciesClient.create()) {

      // Each deny policy is attached to an organization, folder, or project.
      // To work with deny policies, specify the attachment point.
      //
      // Its format can be one of the following:
      // 1. cloudresourcemanager.googleapis.com/organizations/ORG_ID
      // 2. cloudresourcemanager.googleapis.com/folders/FOLDER_ID
      // 3. cloudresourcemanager.googleapis.com/projects/PROJECT_ID
      //
      // The attachment point is identified by its URL-encoded resource name.
      String urlEncodedResource =
          URLEncoder.encode(
              "cloudresourcemanager.googleapis.com/projects/", StandardCharsets.UTF_8);
      String attachmentPoint = String.format("%s%s", urlEncodedResource, projectId);

      // Construct the full path of the resource to which the policy is attached.
      // Its format is: "policies/{attachmentPoint}/denypolicies/{policyId}"
      String policyParent = String.format("policies/%s/denypolicies/%s", attachmentPoint, policyId);

      // Create the DeletePolicy request.
      DeletePolicyRequest deletePolicyRequest =
          DeletePolicyRequest.newBuilder().setName(policyParent).build();

      // Delete the policy and wait for the operation to complete.
      Operation operation =
          policiesClient
              .deletePolicyCallable()
              .futureCall(deletePolicyRequest)
              .get(3, TimeUnit.MINUTES);

      if (operation.hasError()) {
        System.out.println("Error in deleting the policy " + operation.getError());
        return;
      }

      System.out.println("Deleted the deny policy: " + policyId);
    }
  }
}