AWS::Greengrass::SubscriptionDefinition Subscription
Subscriptions define how MQTT messages can be exchanged between devices, functions, and connectors in the group, and with Amazon 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
Amazon CloudFormation template, the Subscriptions
property of the SubscriptionDefinitionVersion
property type contains a list of Subscription
property types.
Syntax
To declare this entity in your Amazon CloudFormation template, use the following syntax:
Properties
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, the ARN of a Lambda function alias (recommended) or version, a connector ARN,
cloud
(which represents the Amazon IoT cloud), orGGShadowService
.Required: Yes
Type: String
Update requires: Replacement
Subject
-
The MQTT topic used to route the message.
Required: Yes
Type: String
Update requires: Replacement
Target
-
The destination of the message. The value can be a thing ARN, the ARN of a Lambda function alias (recommended) or version, a connector ARN,
cloud
(which represents the Amazon IoT cloud), orGGShadowService
.Required: Yes
Type: String
Update requires: Replacement
See also
-
Subscription in the Amazon IoT Greengrass Version 1 API Reference