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Version: 2.6

Pervasive Services

HumanOS provides a large number of services allowing to access data and functions within the node space.

There are three types of services:

  • Server: The service provides a server infrastructure

    • OPC UA Server
    • MT Connect Agent
    • WebService (REST API)
    • ...
  • DataLogger: A DataLogger is a client that proactively sends data to a server.

    • RabbitMQ Publisher
    • MQTT publishers
    • REST API logger (http client)
    • DB Logger (Influx, MySQL, …)
    • File loggers (CSV, ...)
    • Azure IoT Client
    • ...
  • Subscriber: A subscriber is a client which can receive data from a server (broker).

    • RabbitMQ Subscriber
    • MQTT subscribers
    • Azure IoT Client

Event Driven DataLogger

The event driven data logger reports each time the data value changes (event).

  1. Data value changes in the hardware and is read by the UHAL plugin.

  2. The data node in node space is actualized. Parallel the history of the data node gets a new entry in its time series.

  3. If the node filter matches, the data node is transformed into a data set.

    NOTE

    Each field of the data set is filled with the current values and properties of the data node.

  4. The data set is passed to a payload script. Here, the logic transforms the data set into the payload.

  5. The payload is transferred to the outside system using the dedicated protocols.

    NOTE

    Not all data loggers require a payload script. For instance, CSV and Influx have fixed payloads.

Streaming Driven DataLogger

The streaming data logger uses a sampling rate to report the data values.

  1. Data value changes constantly in the hardware and is read by the UHAL plugin.

  2. The data node in node space is actualized. Parallel the history of the data node gets a new entry in its time series.

  3. If the node filter matches, the data node is transformed into a data set in the pace of the sampling rate.

  4. The data set is passed to a payload script. Here, the logic transforms the data set into the payload.

  5. The payload is transferred to the outside system using the dedicated protocols.

The sampler has two options to define how data is sent:

  • OnlyLastValue: only the last value of the sampling is sent.
  • AllData: all data value changes are sent of the sampling.