# TopicSubscriptionConfig

Subscription configuration.

Extends: TopicSubscriptionConfig
Extends: SubscriptionOptions

- Source: [`aws-sns/lib/subscriber.ts`](https://github.com/aws/aws-cdk/blob/v2.274.0/packages/aws-cdk-lib/aws-sns/lib/subscriber.ts#L8)
- Type last changed: v2.45.0 · 6 Oct 2022

## Example

```ts
// The code below shows an example of how to instantiate this type.
// The values are placeholders you should change.
import * as cdk from 'aws-cdk-lib';
import { aws_sns as sns } from 'aws-cdk-lib';
import { aws_sqs as sqs } from 'aws-cdk-lib';
import * as constructs from 'constructs';

declare const construct: constructs.Construct;
declare const dependable: constructs.IDependable;
declare const filterOrPolicy: sns.FilterOrPolicy;
declare const queue: sqs.Queue;
declare const subscriptionFilter: sns.SubscriptionFilter;
const topicSubscriptionConfig: sns.TopicSubscriptionConfig = {
  endpoint: 'endpoint',
  protocol: sns.SubscriptionProtocol.HTTP,
  subscriberId: 'subscriberId',

  // the properties below are optional
  deadLetterQueue: queue,
  deliveryPolicy: {
    healthyRetryPolicy: {
      backoffFunction: sns.BackoffFunction.ARITHMETIC,
      maxDelayTarget: cdk.Duration.minutes(30),
      minDelayTarget: cdk.Duration.minutes(30),
      numMaxDelayRetries: 123,
      numMinDelayRetries: 123,
      numNoDelayRetries: 123,
      numRetries: 123,
    },
    requestPolicy: {
      headerContentType: 'headerContentType',
    },
    throttlePolicy: {
      maxReceivesPerSecond: 123,
    },
  },
  filterPolicy: {
    filterPolicyKey: subscriptionFilter,
  },
  filterPolicyWithMessageBody: {
    filterPolicyWithMessageBodyKey: filterOrPolicy,
  },
  rawMessageDelivery: false,
  region: 'region',
  subscriberScope: construct,
  subscriptionDependency: dependable,
  subscriptionRoleArn: 'subscriptionRoleArn',
};
```

## Properties

- `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.

- `subscriberId`: string (required) — The id of the SNS subscription resource created under `scope`.

  In most
  cases, it is recommended to use the `uniqueId` of the topic you are
  subscribing to.

- `subscriberScope`: [Construct](/cdk/api/v2/docs/constructs.Construct.html) — The scope in which to create the SNS subscription resource.

  **Default:** use the topic as the scope of the subscription, in which case `subscriberId` must be defined.

  Normally you'd
  want the subscription to be created on the consuming stack because the
  topic is usually referenced by the consumer's resource policy (e.g. SQS
  queue policy). Otherwise, it will cause a cyclic reference.

  If this is undefined, the subscription will be created on the topic's stack.

- `subscriptionDependency`: [IDependable](/cdk/api/v2/docs/constructs.IDependable.html) — The resources that need to be created before the subscription can be safely created.

  **Default:** empty list

  For example for SQS subscription, the subscription needs to have a dependency on the SQS queue policy
  in order for the subscription to successfully deliver messages.

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

  **Default:** No subscription role is provided

  Required for a firehose subscription protocol.