# ArnComponents

- Source: [`core/lib/arn.ts`](https://github.com/aws/aws-cdk/blob/v2.275.0/packages/aws-cdk-lib/core/lib/arn.ts#L56)
- Type last changed: v2.273.0 · 8 Oct 2026

## Example

```ts
import { WebSocketIamAuthorizer } from 'aws-cdk-lib/aws-apigatewayv2-authorizers';
import { WebSocketLambdaIntegration } from 'aws-cdk-lib/aws-apigatewayv2-integrations';

// This function handles your connect route
declare const connectHandler: lambda.Function;

const webSocketApi = new apigwv2.WebSocketApi(this, 'WebSocketApi');

webSocketApi.addRoute('$connect', {
  integration: new WebSocketLambdaIntegration('Integration', connectHandler),
  authorizer: new WebSocketIamAuthorizer()
});

// Create an IAM user (identity)
const user = new iam.User(this, 'User');

const webSocketArn = Stack.of(this).formatArn({
  service: 'execute-api',
  resource: webSocketApi.apiId,
});

// Grant access to the IAM user
user.attachInlinePolicy(new iam.Policy(this, 'AllowInvoke', {
  statements: [
    new iam.PolicyStatement({
      actions: ['execute-api:Invoke'],
      effect: iam.Effect.ALLOW,
      resources: [webSocketArn],
    }),
  ],
}));
```

## Properties

- `account`: string — The ID of the AWS account that owns the resource, without the hyphens.

  **Default:** The account the stack is deployed to.

  For example, 123456789012. Note that the ARNs for some resources don't
  require an account number, so this component might be omitted.

- `arnFormat`: [ArnFormat](/cdk/api/v2/docs/aws-cdk-lib.ArnFormat.html) — The specific ARN format to use for this ARN value.

  **Default:** ':' when `arnFormat` is `COLON_RESOURCE_NAME`, '/' otherwise. The deprecated `sep` property takes precedence when specified.

- `partition`: string — The partition that the resource is in.

  **Default:** The AWS partition the stack is deployed to.

  For standard AWS regions, the
  partition is aws. If you have resources in other partitions, the
  partition is aws-partitionname. For example, the partition for resources
  in the China (Beijing) region is aws-cn.

- `region`: string — The region the resource resides in.

  **Default:** The region the stack is deployed to.

  Note that the ARNs for some resources
  do not require a region, so this component might be omitted.

- `resource`: string (required) — Resource type (e.g. "table", "autoScalingGroup", "certificate"). For some resource types, e.g. S3 buckets, this field defines the bucket name.

- `resourceName`: string — Resource name or path within the resource (i.e. S3 bucket object key) or a wildcard such as ``"*"``. This is service-dependent.

- `service`: string (required) — The service namespace that identifies the AWS product (for example, 's3', 'iam', 'codepipeline').