6.3.8 IWoTAssetType

The IWoTAssetType is an Interface representing the WoT asset functionality. It has a component representing a File Object that can be used to upload the WoT TD file. It is defined in Table 13.

Table 13 – IWoTAssetType Definition
Attribute Value
BrowseNameIWoTAssetType
IsAbstractTrue
References NodeClass BrowseName DataType TypeDefinition Other
Subtype of the 0:BaseInterfaceType defined in OPC 10000-5.
1:HasWoTComponentVariable<WoTPropertyName>0:BaseDataType0:BaseDataVariableTypeOP
0:HasPropertyVariableAssetEndpoint0:String0:PropertyTypeO
0:HasComponentObjectWoTFileWoTAssetFileTypeM
Conformance Units
WoT Connectivity Base Functionality

When the asset configuration is complete, the Server may update the internal configuration of existing Variable Nodes or it may add new Variable Nodes to represent the asset. Each WoT property in the forms section of the TD shall have exactly one VariableNode associated with it.

The WoTAsset Object must have hierarchical HasWoTComponent references to the newly created Variable Nodes, one for each WoT property. The BrowseName of the Variable Node shall have a name equal to the WoT property name. The namespace used is server-specific.

The AssetEndpoint Property contains the endpoint where the asset can be found on the network. The syntax of the endpoint is vendor-specific.

If a mapping to a WoT property cannot be done (e.g. the data cannot be read from the connected asset), the built-in status code Bad_ConfigurationError will be returned when the Value of the Variable is read.

Each WoT property type is mapped to the corresponding OPC UA built-in DataType using the following mapping table:

Table 14 – WoT property type mapping
WoT Property Type OPC UA Data Type
BooleanBoolean
NumberDouble
IntegerInt64
ObjectNo mapping
StringString
NullNo mapping
array[Items]Array[of one of above defined types]