DWIS.RigOS.Common.Worker 1.0.5-build.462

DWIS.RigOS.Common.Worker provides the base types used to build DWIS background workers that exchange data with the DWIS Blackboard (OPC-UA) and MQTT brokers. It targets .NET 8 and is packaged with its README and license.

Overview

• DWISWorker is an abstract BackgroundService that owns the DWIS client, MQTT client, query registration, and value publishing/reading loops.
• DWISData is an abstract data container that exposes topic mappings, SPARQL queries, and manifests, plus helper logic for MQTT and Blackboard serialization.
• Property helper types (ScalarProperty, GaussianProperty, GaussianValuesProperty, HistogramProperty, HistogramsProperty) model common value shapes and carry DWIS semantic metadata via SemanticInfo.

Key concepts

• MQTT mapping: DWISData builds a topic-to-property map from attributes named MQTTTopicAttribute or MQTTTopic. It can subscribe to all topics, apply incoming payloads to properties, and serialize current values for publishing.
• Blackboard integration: DWISWorker registers SPARQL queries, injects manifests when needed, subscribes to live OPC-UA values, and updates data properties with live updates.
• Value serialization: Scalars are sent as doubles; Gaussian and histogram values are serialized to JSON for MQTT and OPC-UA updates.

Primary types

• DWISWorker: base class that manages configuration, OPC-UA connection, query registration, MQTT subscription, and value exchange. It provides overridable methods for the main loop, MQTT callback, and publish/read behaviors.
• DWISData: base class for defining the data model and its mappings. Derived classes should define TopicPropertyMap, SparQLQueries, and Manifests via the provided builders.
• Configuration / ConfigurationUpdater: reads and writes a local ../home/config.json with defaults for loop duration, OPC-UA URL, and MQTT settings.
• Entry / LiveValue: internal tracking structures for registered queries and live values.

Typical flow

1. Create a DWISData-derived type with public properties decorated with MQTTTopic attributes and accompanied by DWIS manifest/query metadata (via DWIS.RigOS.Common.Model).
2. Create a DWISWorker-derived type that owns a DWISData instance and calls the provided registration and publish/read helpers.
3. On startup, ConfigurationUpdater loads ../home/config.json (or creates it) and DWISWorker connects to the OPC-UA Blackboard and MQTT broker.
4. DWISWorker registers SPARQL queries and subscribes to live OPC-UA values, then reads and publishes values to MQTT and the Blackboard as needed.

Notes

• Query registration tracks query diffs and live values so that updates arrive via OPC-UA subscriptions.
• Manifest injection occurs if no query results exist, allowing the worker to create the required Blackboard nodes before publishing values.