Metadata

Metadata for data streams

Certain metadata are sent with each stream created. Metadata is only sent for streams created by the ingress components. The endpoints that persist sent metadata are CONNECT data services and Edge Data Store.

The following metadata, created by any AVEVA adapter, is available for streams:

• datasource: This specifies the data source and corresponds to componentId in the adapter configuration. The componentID for this adapter is set by the customer.

• AdapterType: This specifies the type of adapter and corresponds to the componentType in the adapter configuration. The componentType for this adapter is MQTT.

To add and configure a new adapter component, see Configure System components.

Note: All supported endpoints (Edge Data Store, CONNECT data services and PI Server) use datasource. However, any other metadata is only supported on Edge Data Store and CONNECT data services. If you use PI Server as the data endpoint, the Point Source field on a PI point reflects the metadata value.

The following metadata is specific to this adapter:

Generic

• topic: Specifies the MQTT topic string.

• valueField: Specifies the JSONPath expression used to extract the data value from a property within the payload supplied by the MQTT server.

SparkPlug B component

• topicNamespace: Specifies the topic namespace.

• groupId: Specifies the element of the topic namespace that logically groups MQTT Edge of Network (EoN) nodes into the MQTT server and the consuming MQTT clients.

• edgeNodeId: Specifies the element of the topic namespace that uniquely identifies the MQTT EoN node within the infrastructure.

• deviceId: Specifies the element of the topic namespace that identifies a device attached to the MQTT EoN node.

  The metadata level in the System/General facet controls the amount of metadata written to an adapter stream and defines the amount of metadata sent to the OMF endpoints. It can be set in Manage adapter-wide settings to one of the following values:

  Metadata Level	Description	Metadata for Generic	Metadata for SparkPlug B
  None	No metadata	None	None
  Low	Includes only framework related information	AdapterType and datasource	AdapterType and datasource
  Medium	Includes adapter specific information that is considered not sensitive	AdapterType, datasource, topic, and valueField	AdapterType, datasource, topicNamespace, groupId, edgeNodeId, deviceId
  High	All metadata (including potentially sensitive information and control addresses)	AdapterType, datasource, topic, and valueField	AdapterType, datasource, topicNamespace, groupId, edgeNodeId, deviceId

Each stream created for the selected measurement has a unique identifier (stream Id). If you specify a custom stream Id for the measurement in the data selection configuration, the adapter uses that stream Id to create the stream. Otherwise, the adapter constructs the stream Id using the following format:

<AdapterComponentId>.<BaseTopic>.<MetricName>

Note: StreamIdPrefix and DefaultStreamIdPattern settings in the data source configuration affect the naming convention. For more information, see Data source (Sparkplug B).

Metadata for health and diagnostics streams

If you configure a health endpoint, the adapter sends both health and diagnostics streams by default with the following metadata:

• datasource

• AdapterType

For more information around Health and Diagnostics, including the list of streams, see Manage the MQTT adapter.

To manage your diagnostics and metadata settings, see Manage adapter-wide settings.

The adapter may also send its own stream metadata not including health and diagnostics streams. For more information about what custom metadata is included in each stream, see the user guide for your adapter.