mqtt.json

The mqtt.json file is used by LiveRig Collector to organize the Topic configurations to be read from the sources configured at sources.xml.

The LiveRig Collector depends on the Topic values, among other information, to subscribe to an MQTT Topic properly. These values are mapped in the following JSON format, as below:

{
  "rigs": {
    "MQTT-Rig": [
      {
        "name": "pump",
        "topic": "test/+/pump",
        "qos": 0,
        "timestampChannel": "Time",
        "units": [
          {
            "channel": "MotorSpeed",
            "unit": "rpm"
          },
          {
            "channel": "ChemicalRate",
            "unit": "gpm"
          },
          {
            "channel": "MotorCurrent",
            "unit": "A"
          },
          {
            "channel": "MotorSpeed",
            "unit": "rpm"
          },
          {
            "channel": "MotorTorque",
            "unit": "ft-lbs"
          },
          {
            "channel": "MotorVoltage",
            "unit": "V"
          },
          {
            "channel": "Time"
          }
        ]
      },
      {
        "name": "wildcard",
        "topic": "test/temperature",
        "qos": 1,
        "units": [
          {
            "channel": "*"
          }
        ]
      }
    ]
  }
}

The object array under rigs is related to an MQTT source, linking the mqtt.json and sources.xml files through their Rig Name.

Each object from the object array is a Topic configuration, and it follows the format bellow:

Name	Description	Required	Default value
name	An identifier for this Topic configuration.	no
topic	The topic name to subscribe.	yes
qos	The QoS for the subscription.	yes	0
timestampChannel	A channel to use its value as the data's timestamp.	no
units	A list of unit configurations.	yes

The units object array follows the format bellow:

Name	Description	Required
channel	The channel generated from the received MQTT message.	yes
unit	The UoM to associate with the channel value.	no

Note: The unit mapping works as a filter. Only channels declared in the mqtt.json file will have its data transmitted to Live.

As shown in the json example above, one viable configuration for a channel is the wildcard symbol (*). This will output all channels generated from the MQTT message received.

Instead of manually configuring this file, is also possible to use the remote control page MQTT Topics to change the settings easily.