Republish - AWS IoT Core

Republish

The republish (republish) action republishes an MQTT message to another MQTT topic.

Requirements

This rule action has the following requirements:

  • An IAM role that AWS IoT can assume to perform the iot:Publish operation. For more information, see Granting AWS IoT the required access.

    In the AWS IoT console, you can choose or create a role to allow AWS IoT to perform this rule action.

Parameters

When you create an AWS IoT rule with this action, you must specify the following information:

topic

The MQTT topic to which to republish the message.

To republish to a reserved topic, which begins with $, use $$ instead. For example, to republish to the device shadow topic $aws/things/MyThing/shadow/update, specify the topic as $$aws/things/MyThing/shadow/update.

Note

Republishing to reserved job topics is not supported.

Supports substitution templates: Yes

qos

(Optional) The Quality of Service (QoS) level to use when republishing messages. Valid values: 0, 1. The default value is 0. For more information about MQTT QoS, see MQTT.

Supports substitution templates: No

roleArn

The IAM role that allows AWS IoT to publish to the MQTT topic. For more information, see Requirements.

Supports substitution templates: No

Examples

The following JSON example defines a republish action in an AWS IoT rule.

{ "topicRulePayload": { "sql": "SELECT * FROM 'some/topic'", "ruleDisabled": false, "awsIotSqlVersion": "2016-03-23", "actions": [ { "republish": { "topic": "another/topic", "qos": 1, "roleArn": "arn:aws:iam::123456789012:role/aws_iot_republish" } } ] } }

The following JSON example defines a republish action with substitution templates in an AWS IoT rule.

{ "topicRulePayload": { "sql": "SELECT * FROM 'some/topic'", "ruleDisabled": false, "awsIotSqlVersion": "2016-03-23", "actions": [ { "republish": { "topic": "${topic()}/republish", "roleArn": "arn:aws:iam::123456789012:role/aws_iot_republish" } } ] } }