Adapter - MQTT Client
This page describes version 2.0.9 of the adapter.
Overview
This adapter provides MQTT publish-subscribe-based messaging protocol. It is designed for connections with remote locations where a "small code footprint" is required or network bandwidth is limited. The publish-subscribe messaging pattern requires a message broker.
Properties
| Name | Display | Is Required | Comments | Type | Default Value | Maximum Value | Minimum Value | Maximum Length | Minimum Length |
|---|---|---|---|---|---|---|---|---|---|
| brokerAddress | MQTT Broker Address | True | The host address of the MQTT Broker. | string | 1024 | 1 | |||
| brokerPort | MQTT Broker Port | True | The MQTT Broker port. Default: 8883 | integer | 8883 | 65535 | 1 | ||
| usetls | Use TLS | False | Select to use a secure connection to the MQTT Broker. | boolean | true | ||||
| clientId | MQTT ClientID | False | The ClientID must be unique. The broker uses the client ID to identify the client and the current state of the client. | string | 1024 | 1 | |||
| cleanSession | Clean Session | False | Un-Check to establish a persistent connection with the broker. | boolean | true | ||||
| allowPacketFragmentation | Allow Packet Fragmentation | False | Set to allow packet fragmentation of messages. | boolean | true | ||||
| userName | Username | False | Username is required for authentication with MQTT Broker. | string | 1024 | ||||
| password | Password | False | Password is required for authentication with MQTT Broker | password | 100 | ||||
| subscribeTopicName1 | Subscribe Topic Name #1 | False | The MQTT Topic to subscribe to for messages. Requires a corresponding QoS value. | string | 1024 | ||||
| subscribeQos1 | Subscribe QoS #1 | False | The Quality of Service Level (QoS) for the message. Valid values are: (0)-At Most Once, (1)-At Least Once, (2)-Exactly Once | string | 1 | ||||
| subscribeTopicName2 | Subscribe Topic Name #2 | False | The MQTT Topic to subscribe to for messages. Requires a corresponding QoS value. | string | 1024 | ||||
| subscribeQos2 | Subscribe QoS #2 | False | The Quality of Service Level (QoS) for the message. Valid values are: (0)-At Most Once, (1)-At Least Once, (2)-Exactly Once | string | 1 | ||||
| subscribeTopicName3 | Subscribe Topic Name #3 | False | The MQTT Topic to subscribe to for messages. Requires a corresponding QoS value. | string | 1024 | ||||
| subscribeQos3 | Subscribe QoS #3 | False | The Quality of Service Level (QoS) for the message. Valid values are: (0)-At Most Once, (1)-At Least Once, (2)-Exactly Once | string | 1 |
Commands
Subscribe (subscribe)
Subscribes to an MQTT Topic for messages.
Request Properties
| Name | Display | Description | Is Required | Type |
|---|---|---|---|---|
| topic | Topic Name | The MQTT Topic to subscribe to for messages. Requires a corresponding QoS value. | True | string |
| qos | QoS | The Quality of Service Level (QoS) for the message. Valid values are: (0)-At Most Once, (1)-At Least Once, (2)-Exactly Once | True | string |
Unsubscribe (unsubscribe)
Unsubscribes from an MQTT Topic.
Request Properties
| Name | Display | Description | Is Required | Type |
|---|---|---|---|---|
| topic | Topic Name | The MQTT Topic to unsubscribe from. | True | string |
Publish (publish)
Publishes an MQTT payload to a topic.
Request Properties
| Name | Display | Description | Is Required | Type |
|---|---|---|---|---|
| topic | Topic Name | The topic of the message being sent. | True | string |
| payload | Payload | The data content of the message. | False | string |
| qos | QoS | The Quality of Service Level (QoS) for the message. Valid values are: Valid values are: (0)-At Most Once, (1)-At Least Once, (2)-Exactly Once | False | string |
| retain | Retain | Tells the broker to store the last retained message and the corresponding QoS for a topic. | False | boolean |
Events
MQTT Connected (mqttConnected)
The connection to MQTT Broker has been established.
No properties defined
messageArrived (messageArrived)
An MQTT message has arrived.
Event Properties
| Name | Display | Description | Type |
|---|---|---|---|
| data | Data | The payload data as Json. | string |
| topic | Topic Name | The topic of the message received. | string |
| payload | Message Payload | The data content of the message. | string |
| qos | Quality of Service Level | The Quality of Service Level (QoS) for the message. | string |
| retain | Retain | Indicates the last retained message and the corresponding QoS for a topic. | string |
Release History
| Version | Type | Description | Tracking # | Date |
|---|---|---|---|---|
| 2.0.1 | Initial | First release in the Adapter Type store. | ||
| 2.0.5 | Feature | Added multiple subscription fields on the adapter properties. | NAP-12579 | |
| 2.0.7 | Maintenance | Updated third-party components and improved maintainability. | NAP-11518 | |
| 2.0.8 | Maintenance | Updated third-party components and improved maintainability. | NAP-23945 | 2022-11-29 |
| 2.0.9 | Maintenance | Updated third-party components and improved maintainability. | NAP-27635 | 2024-07-31 |