AWS::SNS::Subscription
The AWS::SNS::Subscription
resource subscribes an endpoint to an Amazon SNS topic. For a subscription to be created, the owner of the endpoint must`
confirm the subscription.
Syntax
To declare this entity in your AWS CloudFormation template, use the following syntax:
JSON
{ "Type" : "AWS::SNS::Subscription", "Properties" : { "DeliveryPolicy" :
Json
, "Endpoint" :String
, "FilterPolicy" :Json
, "FilterPolicyScope" :String
, "Protocol" :String
, "RawMessageDelivery" :Boolean
, "RedrivePolicy" :Json
, "Region" :String
, "ReplayPolicy" :Json
, "SubscriptionRoleArn" :String
, "TopicArn" :String
} }
YAML
Type: AWS::SNS::Subscription Properties: DeliveryPolicy:
Json
Endpoint:String
FilterPolicy:Json
FilterPolicyScope:String
Protocol:String
RawMessageDelivery:Boolean
RedrivePolicy:Json
Region:String
ReplayPolicy:Json
SubscriptionRoleArn:String
TopicArn:String
Properties
DeliveryPolicy
-
The delivery policy JSON assigned to the subscription. Enables the subscriber to define the message delivery retry strategy in the case of an HTTP/S endpoint subscribed to the topic. For more information, see
GetSubscriptionAttributes
in the Amazon SNS API Reference and Message delivery retries in the Amazon SNS Developer Guide.Required: No
Type: Json
Update requires: No interruption
Endpoint
-
The subscription's endpoint. The endpoint value depends on the protocol that you specify. For more information, see the
Endpoint
parameter of theSubscribe
action in the Amazon SNS API Reference.Required: No
Type: String
Update requires: Replacement
FilterPolicy
-
The filter policy JSON assigned to the subscription. Enables the subscriber to filter out unwanted messages. For more information, see
GetSubscriptionAttributes
in the Amazon SNS API Reference and Message filtering in the Amazon SNS Developer Guide.Required: No
Type: Json
Update requires: No interruption
FilterPolicyScope
-
This attribute lets you choose the filtering scope by using one of the following string value types:
-
MessageAttributes
(default) - The filter is applied on the message attributes. -
MessageBody
- The filter is applied on the message body.
Note
Null
is not a valid value forFilterPolicyScope
. To delete a filter policy, delete theFilterPolicy
property but keepFilterPolicyScope
property as is.Required: No
Type: String
Update requires: No interruption
-
Protocol
-
The subscription's protocol. For more information, see the
Protocol
parameter of theSubscribe
action in the Amazon SNS API Reference.Required: Yes
Type: String
Update requires: Replacement
RawMessageDelivery
-
When set to
true
, enables raw message delivery. Raw messages don't contain any JSON formatting and can be sent to Amazon SQS and HTTP/S endpoints. For more information, seeGetSubscriptionAttributes
in the Amazon SNS API Reference.Required: No
Type: Boolean
Update requires: No interruption
RedrivePolicy
-
When specified, sends undeliverable messages to the specified Amazon SQS dead-letter queue. Messages that can't be delivered due to client errors (for example, when the subscribed endpoint is unreachable) or server errors (for example, when the service that powers the subscribed endpoint becomes unavailable) are held in the dead-letter queue for further analysis or reprocessing.
For more information about the redrive policy and dead-letter queues, see Amazon SQS dead-letter queues in the Amazon SQS Developer Guide.
Required: No
Type: Json
Update requires: No interruption
Region
-
For cross-region subscriptions, the region in which the topic resides.
If no region is specified, AWS CloudFormation uses the region of the caller as the default.
If you perform an update operation that only updates the
Region
property of aAWS::SNS::Subscription
resource, that operation will fail unless you are either:-
Updating the
Region
fromNULL
to the caller region. -
Updating the
Region
from the caller region toNULL
.
Required: No
Type: String
Update requires: Some interruptions
-
ReplayPolicy
-
Specifies whether Amazon SNS resends the notification to the subscription when a message's attribute changes.
Required: No
Type: Json
Update requires: No interruption
SubscriptionRoleArn
-
This property applies only to Amazon Data Firehose delivery stream subscriptions. Specify the ARN of the IAM role that has the following:
-
Permission to write to the Amazon Data Firehose delivery stream
-
Amazon SNS listed as a trusted entity
Specifying a valid ARN for this attribute is required for Firehose delivery stream subscriptions. For more information, see Fanout to Amazon Data Firehose delivery streams in the Amazon SNS Developer Guide.
Required: No
Type: String
Update requires: No interruption
-
TopicArn
-
The ARN of the topic to subscribe to.
Required: Yes
Type: String
Update requires: Replacement
Return values
Ref
When you pass the logical ID of this resource to the intrinsic Ref
function, Ref
returns the subscription's logical name. This attribute allows you to
reference the logical name of the subscription resource within the CloudFormation
template.
For example, if you have a subscription resource named 'MySubscription', you can use '!Ref MySubscription' to refer to its logical name in other parts of the CloudFormation template.
For more information about using the Ref
function, see Ref
.
Fn::GetAtt
The Fn::GetAtt
intrinsic function returns a value for a specified attribute of this type. The following are the available attributes and sample return values.
For more information about using the Fn::GetAtt
intrinsic function, see Fn::GetAtt
.
Arn
-
Returns the ARN of the subscription created by the AWS::SNS::Subscription resource.
Examples
Create a subscription with mandatory attributes
The following example creates a subscription with only an endpoint, protocol, and topic ARN.
JSON
"MySubscription" : { "Type" : "AWS::SNS::Subscription", "Properties" : { "Endpoint" : "test@example.com", "Protocol" : "email", "TopicArn" : { "Ref" : "MySNSTopic" } } }
YAML
MySubscription: Type: AWS::SNS::Subscription Properties: Endpoint: test@example.com Protocol: email TopicArn: !Ref 'MySNSTopic'
Create a subscription with optional attributes
The following example creates a subscription with a filter policy, delivery policy, and raw message delivery enabled.
Note
You can set subscription attributes only on standalone Amazon SNS subscriptions (not on subscriptions nested in topics).
YAML
AWSTemplateFormatVersion: 2010-09-09 Resources: CarSalesTopic: Type: 'AWS::SNS::Topic' ERPSubscription: Type: 'AWS::SNS::Subscription' Properties: TopicArn: !Ref CarSalesTopic Endpoint: !GetAtt - ERPIntegrationQueue - Arn Protocol: sqs RawMessageDelivery: 'true' CRMSubscription: Type: 'AWS::SNS::Subscription' Properties: TopicArn: !Ref CarSalesTopic Endpoint: !GetAtt - CRMIntegrationQueue - Arn Protocol: sqs RawMessageDelivery: 'true' FilterPolicy: buyer-class: - vip SCMSubscription: Type: 'AWS::SNS::Subscription' Properties: TopicArn: !Ref CarSalesTopic Endpoint: !Ref myHttpEndpoint Protocol: https DeliveryPolicy: healthyRetryPolicy: numRetries: 20 minDelayTarget: 10 maxDelayTarget: 30 numMinDelayRetries: 3 numMaxDelayRetries: 17 numNoDelayRetries: 0 backoffFunction: exponential ERPIntegrationQueue: Type: 'AWS::SQS::Queue' Properties: {} CRMIntegrationQueue: Type: 'AWS::SQS::Queue' Properties: {} Parameters: myHttpEndpoint: Type: String
JSON
{ "AWSTemplateFormatVersion": "2010-09-09", "Resources": { "CarSalesTopic": { "Type": "AWS::SNS::Topic" }, "ERPSubscription": { "Type": "AWS::SNS::Subscription", "Properties": { "TopicArn": { "Ref": "CarSalesTopic" }, "Endpoint": { "Fn::GetAtt": ["ERPIntegrationQueue", "Arn"] }, "Protocol": "sqs", "RawMessageDelivery": "true" } }, "CRMSubscription": { "Type": "AWS::SNS::Subscription", "Properties": { "TopicArn": { "Ref": "CarSalesTopic" }, "Endpoint": { "Fn::GetAtt": ["CRMIntegrationQueue", "Arn"] }, "Protocol": "sqs", "RawMessageDelivery": "true", "FilterPolicy": { "buyer-class": [ "vip" ] } } }, "SCMSubscription": { "Type": "AWS::SNS::Subscription", "Properties": { "TopicArn": { "Ref": "CarSalesTopic" }, "Endpoint": { "Ref": "myHttpEndpoint" }, "Protocol": "https", "DeliveryPolicy": { "healthyRetryPolicy": { "numRetries": 20, "minDelayTarget": 10, "maxDelayTarget": 30, "numMinDelayRetries": 3, "numMaxDelayRetries": 17, "numNoDelayRetries": 0, "backoffFunction": "exponential" } } } }, "ERPIntegrationQueue": { "Type": "AWS::SQS::Queue", "Properties": {} }, "CRMIntegrationQueue": { "Type": "AWS::SQS::Queue", "Properties": {} } }, "Parameters": { "myHttpEndpoint": { "Type": "String" } } }