AWS CloudFormation
User Guide (API Version 2010-05-15)

AWS IoT Greengrass SubscriptionDefinitionVersion Subscription

Subscriptions define how MQTT messages can be exchanged between devices, functions, and connectors in the group, and with AWS IoT or the local shadow service. A subscription defines a message source, message target, and a topic (or subject) that's used to route messages from the source to the target. A subscription defines the message flow in one direction, from the source to the target. For two-way communication, you must set up two subscriptions, one for each direction.

In an AWS CloudFormation template, the Subscriptions property of the AWS::Greengrass::SubscriptionDefinitionVersion resource contains a list of Subscription property types.

Syntax

To declare this entity in your AWS CloudFormation template, use the following syntax:

JSON

{ "Target" : String, "Id" : String, "Source" : String, "Subject" : String }

YAML

Target: String Id: String Source: String Subject: String

Properties

Target

The destination of the message. The value can be a thing ARN, a Lambda function ARN, a connector ARN, cloud (which represents the AWS IoT cloud), or GGShadowService.

Required: Yes

Type: String

Update requires: Replacement

Id

A descriptive or arbitrary ID for the subscription. This value must be unique within the subscription definition version. Maximum length is 128 characters with pattern [a-zA-Z0-9:_-]+.

Required: Yes

Type: String

Update requires: Replacement

Source

The originator of the message. The value can be a thing ARN, a Lambda function ARN, a connector ARN, cloud (which represents the AWS IoT cloud), or GGShadowService.

Required: Yes

Type: String

Update requires: Replacement

Subject

The MQTT topic used to route the message.

Required: Yes

Type: String

Update requires: Replacement

See Also

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