7.2.5.6.2 ActionRequest
A NetworkMessage with MessageType “ua-action-request” contains a JSON array with ActionRequest messages. A ActionRequest message is a JSON object with the fields defined in Table 196.
All fields are encoded using CompactEncoding OPC UA JSON Data Encoding defined in OPC 10000-6 .
| Name | Type | Description |
| DataSetWriterId | UInt16 | An identifier for DataSetWriter in the Responder which creates the Response. This value is mandatory. It is unique within the scope of a Responder. |
| ActionTargetId | UInt16 | The numeric identifier assigned to the Action target which is unique within one ActionMetaData. This value is mandatory. It is used to address the Action target in combination with the PublisherId and the DataSetWriterId. |
| DataSetWriterName | String | The name of the DataSetWriter which created the DataSetMessage. The presence of the value depends on the setting in the JsonDataSetMessageContentMask. |
| WriterGroupName | String | The name of the WriterGroup which created the DataSetMessage. The presence of the value depends on the setting in the JsonDataSetMessageContentMask. The value shall be omitted if the WriterGroupName is contained in the NetworkMessage header. |
| MetaDataVersion | ConfigurationVersionDataType | The version of the ActionMetaData Request which describes the contents of the Payload. The presence of the value depends on the setting in the JsonDataSetMessageContentMask. |
| MinorVersion | VersionTime | The minor version of the ActionMetaData Request which describes the contents of the Payload. The presence of the value depends on the setting in the JsonDataSetMessageContentMask. The value shall be omitted if the MetaDataVersion is contained in the DataSetMessage header. |
| Timestamp | DateTime | The time the Request was created. The presence of the value depends on the setting in the JsonDataSetMessageContentMask. |
| MessageType | String | “ua-action-request” The presence of the value depends on the setting in the JsonDataSetMessageContentMask. |
| RequestId | UInt16 | Data provided by the Requestor in the Request message that is returned to the Requestor in the Response message. |
| ActionState | ActionState | Specifies the expected Action state on Responder side. The details for the use of this value and the relation to other values for a Action execution is defined in 6.2.11.2. |
| Payload | Object | A JSON object containing the name-value pairs specified by the ActionMetaData. The format of the value depends on the DataType of the field and the flags specified by the DataSetFieldContentMask. Only Variant or RawData encoding shall be allowed. If bits for DataValue encoding are set, the Variant encoding shall be used. |
The encoding rules defined in 7.2.5.4 for DataSetMessages also apply to the ActionRequest message. The DataValue encoding shall not be used in ActionRequest message. The RawData flag shall be FALSE for ActionRequest messages.