7.2.5.5.7 ActionMetaData
A NetworkMessage with MessageType ActionMetaData is a JSON object with the fields defined in Table 193.
All fields are encoded using CompactEncoding OPC UA JSON Data Encoding defined in OPC 10000-6 .
| Name | Type | Description |
| MessageId | String | A globally unique identifier for the message. This value is mandatory. |
| MessageType | String | This value shall be “ua-action-metadata”. This value is mandatory. |
| PublisherId | String | The Publisher that sent the message. This value is mandatory. |
| DataSetWriterId | UInt16 | An identifier for DataSetWriter which published the metadata. This value is mandatory. It is unique within the scope of a Publisher. |
| DataSetWriterName | String | The name of the DataSetWriter. This value is optional. The presence of the value depends on the setting in the JsonDataSetMessageContentMask. |
| Timestamp | UtcTime | When the message was first sent to the Middleware. This value is mandatory. |
| ActionTargets | ActionTargetDataType[] | The set of Action targets that may be executed. If an Action target is mapped to a Method of an Object in an OPC UA Server, then the related Object and Method are defined by the corresponding entry in the ActionMethods array. The ActionTargetId in the ActionTargetDataType is used to address the Method referenced by the ActionMethodDataType. |
| Request | DataSetMetaDataType | The structure and content of the ActionRequest message. The name of the Action is defined by the Name field in the DataSetMetaDataType. |
| Response | DataSetMetaDataType | The structure and content of the ActionResponse message. The fields Name and ConfigurationVersion of the Request and the Response DataSetMetaDataType shall have equal values. |
| ActionMethods | ActionMethodDataType[] | The optional array of Action sources. If the source information is provided, the array shall match the size and order of the ActionTargets. |