Outgoing MQTT packages

The outgoing MQTT packages are in JSON format. An MQTT package only contains data from a single attribute.

MQTT package structure

{
  "Hierarchy": "StressTest_grpc/StressTest_1/StressTest_1_3",
  "IED_Model": "IED 427 Factory 1",
  "Name": "StressTest_1_3",
  "Topic": "factory_1/motors/StressTest_grpc/StressTest_1/StressTest_1_3",
  "datapoints": [
    {
      "Measurement": "15151",
      "Quality_Code": "192",
      "Time": "2024-06-13T13:05:21.000Z"
    },
    {
      "Measurement": "15152",
      "Quality_Code": "192",
      "Time": "2024-06-13T13:05:22.000Z"
    }
  ]
}

The first four items of the JSON object belong to the header. The fifth item (datapoints) contains an array with the data points, i.e. data points in a payload, defined in the configuration file. The length of the array depends on the message publish interval, as it defines for how long the data points of an attribute will be sampled before sending out the MQTT package but at the same time it will be kept under the maximum MQTT package size.

MQTT packages will be sent out every message publish interval. If the sampled data within this time period exceeds the maximum MQTT package size, the data will be split into smaller packages that meet the sizing requirements. This outgoing MQTT package was sent out using the configuration file shown in Creating a configuration file.

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