UA Part 14: PubSub - 9.1.4.2.1 PublishedDataSetType

This ObjectType is the base type for PublishedDataSets. It defines the metadata and the configuration version of the DataSets sent as DataSetMessages through DataSetWriters.

The PublishedDataSetType is the base type for configurable DataSets. Derived types like PublishedDataItemsType and PublishedEventsType defines how to collect the DataSet to be published. For PublishedDataItemsType this is a list of monitored Variables. For PublishedEventsType this is an Event selection. The list of monitored Variables or the list of selected EventFields defines the content and metadata of the PublishedDataSetType Object.

If the content of the DataSet is defined by a product specific configuration and the source of the DataSet is not known, the PublishedDataSetType can be used directly to expose the PublishedDataSet in the AddressSpace of the Publisher.

The PublishedDataSetType is formally defined in Table 105.

Table 105 – PublishedDataSetType Definition

Attribute	Value
BrowseName	PublishedDataSetType
IsAbstract	False
References	Node Class	BrowseName	DataType	TypeDefinition	Modelling Rule
Subtype of BaseObjectType defined in OPC 10000-5.
DataSetToWriter	Object	<DataSetWriterName>		DataSetWriterType	Optional‌Placeholder
HasProperty	Variable	ConfigurationVersion	Configuration‌VersionDataType	PropertyType	Mandatory
HasProperty	Variable	DataSetMetaData	DataSetMeta‌DataType	PropertyType	Mandatory
HasProperty	Variable	DataSetClassId	Guid	PropertyType	Optional
HasComponent	Object	ExtensionFields		ExtensionFieldsType	Optional

The PublishedDataSetType ObjectType is a concrete type and can be used directly. It can be used to expose a PublishedDataSet where the data collection is not visible in the AddressSpace.

The Object has a list of DataSetWriters. A DataSetWriter sends DataSetMessages created from DataSets through a Message Oriented Middleware. The link between the PublishedDataSet Object and a DataSetWriter shall be created when an instance of the DataSetWriterType is created. The DataSetWriterType is defined in 9.1.7.2. If a DataSetWriter is created for the PublishedDataSet, it is added to the list using the ReferenceType DataSetToWriter. The DataSetToWriter ReferenceType is defined in 9.1.4.2.5. If a DataSetWriter for the PublishedDataSet is removed from a group, the Reference to this DataSetWriter shall also be removed from this list. The group model is defined in 9.1.6.

The Property ConfigurationVersion is related to configuration of the DataSet produced by the PublishedDataSet Object. The PublishedDataSet parameters affecting the version are defined in the concrete types derived from this base type. The ConfigurationVersionDataType and the rules for setting the version are defined in 6.2.2.1.5.

The Property DataSetMetaData provides the information necessary to decode DataSetMessages on the Subscriber side if the DataSetMessages are not self-describing. The information in this Property is automatically updated if the ConfigurationVersion is changed based on DataSet configuration change. The DataSetMetaDataType is defined in 6.2.2.1.2. The Name field in the DataSetMetaDataType shall match the name of the PublishedDataSetType Object if the DataSetMetaData is not based on a DataSetClass.

The DataSetClassId is the globally unique identifier for a DataSetClass. The optional Property shall be present if the DataSetClassId of the DataSetMetaData is not null. If the DataSetClassId is set, the Publisher shall reject any configuration changes that change the DataSetMetaData.

The ExtensionFields Object allows the configuration of fields with values to be included in the DataSet in case the existing AddressSpace of the Publisher does not provide the necessary information. The extension fields are added as Properties to the ExtensionFields Object. For PublishedDataItemsType base PublishedDataSets, an extension field is included as a Variable in the published DataSet. For PublishedEventsType base PublishedDataSets, an extension field is included into the SelectedFields for the DataSet.