Protocols/MQTT

The `Protocols/MQTT` category contains nodes that are used in sending and receiving data using the MQTT standard protocol.

Client

This node connects to a configured MQTT Broker.  It allows data to be sent and received over multiple topics from the same broker.   The number of topics can be configured from settings.

Inputs

1. enable - Boolean input that enables the connection to MQTT Broker when `true` and disables the connection when `false`.
   
2. 1 | - Topic 1 input.  Any data type.
   
3. x | - x-th topic input. Any data type.  The number of topic inputs can be configured from Settings.
   

Outputs

1. connected - Boolean output value, `true` if successfully connected to MQTT Broker and `false` if connection cannot be established.
   
2. | 1 - Topic 1 output value. 
   
3. | x - x-th topic output value.  The number of topic inputs can be configured from Settings.

Settings

1. Name - Name of the node.
   
2. Enable - Toggle switch to enable or disable the node.
   
3. Don't use env settings - Toggle switch to select whether or not to use the MQTT Broker details configured in the  .env file configured from Rubix platform.   If the .env file is not configured with the MQTT Broker details then manual configuration of MQTT must be set.
   
4. When `don't use env setings` enabled:
   
1. Use authentication - Toggle switch to enable or disable the use of authentication on the MQTT broker.
   
2. Broker URL - URL/Host of the MQTT broker.
   
3. Broker port - Port number of the MQTT broker.
   
4. User name - User name of the MQTT broker if authentication is enabled.
   
5. Password - Password of the MQTT broker if authentication is enabled.
   
5. Number of Topics - Number of topics required.
   
6. Decimal Places (Numerics) - Decimal precision of numeric topics required.
   
7. Output Type - Drop-down to select output type of topics. Can be the payload delivered to the MQTT broker, or can be JSON formatted string.
   

Operation

This node connects to a configured MQTT Broker, subscribes to topics, and can publish values to topics.  Once configured (in Settings) with a valid ‘Broker URL’, ‘Broker Port’, and ‘Authentication’ (if required), this node will read and write to MQTT topics when ‘enable’ is ‘true’.  Number of topics, and the topic names can be configured from Settings.  Each topic will have a corresponding input and output.

Topic Builder

This node combines string inputs into a `/` seperated MQTT topic.  The number of string inputs can be configured from Settings

Inputs

1. string 1 - First string input value.  Start of the `output` MQTT topic.
   
2. string 2 - Second string input value.
   
3. string x - x-th string input value.  The number of string inputs can be configured from Settings.
   

Outputs

1. output - MQTT topic string output made from adding `/` between each of the string inputs.
   

Settings

1. Name - Name of the node.
   
2. Input count - Number of inputs required.
   
3. string 1 / string2 / string x / ... - Fallback for wired input string values.
   

Operation

This node takes String inputs and concatenates/joins them with `/` to produce an MQTT Topic ‘output’.  The number of inputs can be modified from Settings.

Related Articles:

1. Rubix Wires: Getting Started Guide