Update a deny policy

Update the deny rules and/ or its display name after policy creation.

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

Code sample

Go

To learn how to install and use the client library for IAM, see IAM client libraries. For more information, see the IAM Go 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 (
	"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
}

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.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);
    }
  }
}

Node.js

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

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

/**
 * 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();

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 update_deny_policy(project_id: str, policy_id: str, etag: str) -> None:
    from google.cloud import iam_v2
    from google.cloud.iam_v2 import types

    """
    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.
    """
    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__":
    import uuid

    # Your Google Cloud project ID.
    project_id = "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)

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