# Subscription

A new subscription.

Prefer to use the `ITopic.addSubscription()` methods to create instances of
this class.

Extends: Construct › Resource › Subscription
Implements: IResource, IEnvironmentAware, IConstruct, IDependable

- CloudFormation: [`AWS::SNS::Subscription`](https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/aws-resource-sns-subscription.html)
- L1 type: [`CfnSubscription`](/cdk/api/v2/docs/aws-cdk-lib.aws_sns.CfnSubscription.html)
- Source: [`aws-sns/lib/subscription.ts`](https://github.com/aws/aws-cdk/blob/v2.274.0/packages/aws-cdk-lib/aws-sns/lib/subscription.ts#L99)
- Type last changed: v2.196.0 · 16 May 2025

## Example

```ts
// producerStack defines an SNS topic
declare const topic: sns.Topic;

// consumerStack subscribes to it with a weak reference,
// so the producer can be torn down without blocking on this consumer
const consumerStack = new Stack(app, 'Consumer', {
  env: { account: '123456789012', region: 'us-east-1' },
});
new sns.Subscription(consumerStack, 'Subscription', {
  topic: sns.Topic.fromTopicArn(consumerStack, 'Topic', Stack.consumeReference(topic.topicArn)),
  endpoint: 'https://example.com/webhook',
  protocol: sns.SubscriptionProtocol.HTTPS,
});
```

## Initializer

```ts
new Subscription(scope: Construct, id: string, props: SubscriptionProps)
```

## Construct Props

- `deadLetterQueue`: [IQueue](/cdk/api/v2/docs/aws-cdk-lib.aws_sqs.IQueue.html) — Queue to be used as dead letter queue.

  **Default:** No dead letter queue enabled.

  If not passed no dead letter queue is enabled.

- `deliveryPolicy`: [DeliveryPolicy](/cdk/api/v2/docs/aws-cdk-lib.aws_sns.DeliveryPolicy.html) — The delivery policy.

  **Default:** if the initial delivery of the message fails, three retries with a delay between failed attempts set at 20 seconds

- `endpoint`: string (required) — The subscription endpoint.

  The meaning of this value depends on the value for 'protocol'.

- `filterPolicy`: { [key: string]: [SubscriptionFilter](/cdk/api/v2/docs/aws-cdk-lib.aws_sns.SubscriptionFilter.html) } — The filter policy.

  **Default:** all messages are delivered

- `filterPolicyWithMessageBody`: { [key: string]: [FilterOrPolicy](/cdk/api/v2/docs/aws-cdk-lib.aws_sns.FilterOrPolicy.html) } — The filter policy that is applied on the message body.

  **Default:** all messages are delivered

  To apply a filter policy to the message attributes, use `filterPolicy`. A maximum of one of `filterPolicyWithMessageBody` and `filterPolicy` may be used.

- `protocol`: [SubscriptionProtocol](/cdk/api/v2/docs/aws-cdk-lib.aws_sns.SubscriptionProtocol.html) (required) — What type of subscription to add.

- `rawMessageDelivery`: boolean = false — true if raw message delivery is enabled for the subscription.

  Raw messages are free of JSON formatting and can be
  sent to HTTP/S and Amazon SQS endpoints. For more information, see GetSubscriptionAttributes in the Amazon Simple
  Notification Service API Reference.

- `region`: string — The region where the topic resides, in the case of cross-region subscriptions.

  **Default:** the region where the CloudFormation stack is being deployed.

- `subscriptionRoleArn`: string — Arn of role allowing access to firehose delivery stream.

  **Default:** No subscription role is provided

  Required for a firehose subscription protocol.

- `topic`: [ITopic](/cdk/api/v2/docs/aws-cdk-lib.aws_sns.ITopic.html) (required) — The topic to subscribe to.

## Properties

- `deadLetterQueue`: [IQueue](/cdk/api/v2/docs/aws-cdk-lib.aws_sqs.IQueue.html) — The DLQ associated with this subscription if present.

- `env`: [ResourceEnvironment](/cdk/api/v2/docs/aws-cdk-lib.interfaces.ResourceEnvironment.html) — The environment this resource belongs to.

  For resources that are created and managed in a Stack (those created by
  creating new class instances like `new Role()`, `new Bucket()`, etc.), this
  is always the same as the environment of the stack they belong to.

  For referenced resources (those obtained from referencing methods like
  `Role.fromRoleArn()`, `Bucket.fromBucketName()`, etc.), they might be
  different than the stack they were imported into.

- `node`: [Node](/cdk/api/v2/docs/constructs.Node.html) — The tree node.

- `PROPERTY_INJECTION_ID`: string (static) — Uniquely identifies this class.

- `stack`: [Stack](/cdk/api/v2/docs/aws-cdk-lib.Stack.html) — The stack in which this resource is defined.

## Methods

- `applyCrossStackReferenceStrength(strength: ReferenceStrength): void` — Override the cross-stack reference strength for this resource.

  When set, any cross-stack reference to this resource will use the specified
  mechanism instead of the global default determined by the
  `@aws-cdk/core:defaultCrossStackReferences` context key. This is useful for
  selectively weakening specific references to avoid the "deadly embrace" problem
  without changing the app-wide default.

  **Parameters**

  - `strength` — - The reference strength to use for this resource.

- `applyRemovalPolicy(policy: RemovalPolicy): void` — Apply the given removal policy to this resource.

  The Removal Policy controls what happens to this resource when it stops
  being managed by CloudFormation, either because you've removed it from the
  CDK application or because you've made a change that requires the resource
  to be replaced.

  The resource can be deleted (`RemovalPolicy.DESTROY`), or left in your AWS
  account for data recovery and cleanup later (`RemovalPolicy.RETAIN`).

- `isConstruct(x: any): boolean` (static) — Checks if `x` is a construct.

  Use this method instead of `instanceof` to properly detect `Construct`
  instances, even when the construct library is symlinked.

  Explanation: in JavaScript, multiple copies of the `constructs` library on
  disk are seen as independent, completely different libraries. As a
  consequence, the class `Construct` in each copy of the `constructs` library
  is seen as a different class, and an instance of one class will not test as
  `instanceof` the other class. `npm install` will not create installations
  like this, but users may manually symlink construct libraries together or
  use a monorepo tool: in those cases, multiple copies of the `constructs`
  library can be accidentally installed, and `instanceof` will behave
  unpredictably. It is safest to avoid using `instanceof`, and using
  this type-testing method instead.

  **Parameters**

  - `x` — Any object.

  **Returns:** true if `x` is an object created from a class which extends `Construct`.

- `isOwnedResource(construct: IConstruct): boolean` (static) — Returns true if the construct was created by CDK, and false otherwise.

- `isResource(construct: IConstruct): boolean` (static) — Check whether the given construct is a Resource.

- `toString(): string` — Returns a string representation of this construct.

- `with(...mixins: IMixin[]): IConstruct` — Applies one or more mixins to this construct.

  Mixins are applied in order. The list of constructs is captured at the
  start of the call, so constructs added by a mixin will not be visited.
  Use multiple `with()` calls if subsequent mixins should apply to added
  constructs.