Data types

The OPC UA API utilizes different data types. Some of the data types are defined by the OPC UA Foundation and use the OPC UA Foundation JSON serializers. The documentation will list the data types used and show the corresponding JSON and default values. The default values are used when they are not set.

Note that the JSON is case-sensitive

SignalR and RESTFul API Data types

The following types are exposed directly in the API. They consist of smaller data types which are referenced further down in the document.

Connection

Used when creating a connection.

Members	Data type	Description	Default value
Url	String	The address of the ua server. E.g. opc.tcp://10.100.12.43:7653
AuthenticationType	UInt32	AnonymousUnsecure = 1, AnonymousSecure = 2

ReadValuesRequest

Used when reading values (i.e. value of attributes with id = 13).

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
NodeIds	Array of NodeId	Contains the node ids to read.

ReadValuesResponse

This the response when reading values of nodes.

Members	Data type	Description	Default value
Success	Boolean	False if no values were read.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
Values	Array of DataValue	An array containing the values of the node. The order is the same as in the Request

WriteValuesRequest

Used when writing values (i.e. value of attributes with id = 13).

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
WriteValues	Array of WriteNodeValue	Contains the node ids and values to be written.

WriteNodeValue

Contains a NodeId and a DataValue. Is used when writing values.

Members	Data type	Description	Default value
NodeId	NodeId	The id of the node to write to.
Value	DataValue	Contains the value to be written.

WriteValuesResponse

This the response when writing values to a node.

Members	Data type	Description	Default value
Success	Boolean	False if no values were written.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
Values	Array of StatusCode	An array status of the write operation. The order is the same as in the Request

ReadDataTypesRequest

Used when reading datatypes

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
NodeIds	Array of NodeId	Contains the node ids to read.

ReadDataTypesResponse

This the response when reading data types of nodes.

Members	Data type	Description	Default value
Success	Boolean	False if no values were read.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
Values	Array of DataTypeInfo	An array containing the values of the node. The order is the same as in the Request

DataTypeInfo

Members	Data type	Description
StatusCode	StatusCode	Status code of the read.
DataTypeId	NodeId	Only present if StatusCode is good, and contains the node id of the data type.
BrowseName	QualifiedName	Only present if StatusCode is good, and contains the browse name of the data type.

ReadAttributesRequest

Used when reading attributes. The ReadValueIds is an array of node ids and the attribute id it will read.

See Attributes.

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
ReadValueIds	Array of ReadValueId	Contains the node ids and the attributes to read.

ReadAttributesResponse

This the response when reading attributes.

Members	Data type	Description	Default value
Success	Boolean	False if no attributes were read.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
Values	Array of DataValue	An array containing the values of the attributes. The order is the same as in the Request

WriteAttributesRequest

Used when writing attributes.

See Attributes.

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
WriteValues	Array of WriteValue	Contains the node id, the attributes and the values to be written.

WriteAttributesResponse

This the response when writing attributes.

Members	Data type	Description	Default value
Success	Boolean	False if no values were written.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
Values	Array of StatusCode	An array status of the write operation. The order is the same as in the Request

ReadHistoryRawValuesRequest

Used when reading raw history data.

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
IsReadModified	Boolean		false
StartTime	DateTime	The start time of the query
EndTime	DateTime	The end time of the query
ReturnBounds	Boolean	Return bounds if true	false
TimestampsToReturn	Int32	See TimestampsToReturn
ReadValueIds	Array of HistoryReadValueId	The nodes to read history for
Limit	Limit	Limit the number of vales returned from the request

ReadHistoryRawValuesResponse

Response when reading raw history.

Members	Data type	Description	Default value
Success	Boolean	False if no values were read.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
HistoryReadResults	Array of HistoryDataValueResult	An array of historical values. The array is in the same order as the Request

HistoryReadValueId

Members	Data type	Description	Default value
NodeId	NodeId	The node id of the node to read history from.
IndexRange	String	The index reange.	null
DataEncoding	QualifiedName	The data encoding.	null

HistoryDataValueResult

Represents a historical read result for one node id.

Members	Data type	Description
NodeId	NodeId	The id of the node which was read.
StatusCode	StatusCode	Contains the status code of the historical read operations.
DataValues	Array of DataValue	The historical values.

ReadHistoryProcessedValuesRequest

Used when reading processed history data.

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
StartTime	DateTime	The start time of the query
EndTime	DateTime	The end time of the query
ProcessingInterval	double	Interval between returned Aggregate values. The value 0 indicates that there is no ProcessingInterval defined. The value is given in milliseconds.
AggregateType	NodeId	The NodeId of the HistoryAggregate object that is to be used when retrieving the processed history.
AggregateName	String	The name of the aggregate. Only one of AggregateName and AggregateType should be set simultaneously. AttributeType has precedence
TimestampsToReturn	Int32	See TimestampsToReturn
ReadValueIds	Array of HistoryAggregateReadValueId	The nodes to read history for

HistoryAggregateReadValueId

Members	Data type	Description	Default value
NodeId	NodeId	The node id of the node to read history from.
IndexRange	String	The index reange.	null
DataEncoding	QualifiedName	The data encoding.	null
AggregateType	NodeId	The NodeId of the HistoryAggregate object that is to be used when retrieving the processed history.
AggregateName	String	The name of the aggregate. Only one of AggregateName and AggregateType should be set simultaneously. AttributeType has precedence

ReadHistoryProcessedValuesResponse

Response when reading processed history.

Members	Data type	Description	Default value
Success	Boolean	False if no values were read.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
HistoryReadResults	Array of HistoryDataValueResult	An array of historical values. The array is in the same order as the Request

HistoryAggregateRequest

Used when getting aggregates from a server.

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.

HistoryAggregateResponse

Response when reading history aggregates.

Members	Data type	Description	Default value
Success	Boolean	False if aggregates could not be read.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
Aggregates	Array of HistoryAggregate	An array of aggregates available in the server.

HistoryAggregate

Represents one aggregate option.

Members	Data type	Description	Default value
NodeId	NodeId	The id of the node representing the aggregate.
Name	String	The name of the aggregate.

HistoryWriteRequest

Used when writing historical data to an OPC UA Server.

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
UpdateDataDetails	Array of UpdateDataDetails	The connection info.

UpdateDataDetails

Members	Data type	Description	Default value
PerformInsertReplace	PerformUpdateType	Decides whether the data shall be inserted, updated or replaced.	null
UpdateValues	Array of DataValue	The values to be written.

HistoryWriteResponse

Response when writing historical data.

Members	Data type	Description	Default value
Success	Boolean	False if aggregates could not be read.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
HistoryUpdateResults	Array of HistoryUpdateResult	The result of the write operation.

HistoryUpdateResult

Members	Data type	Description
StatusCode	StatusCode	The result of the operation.
OperationResults	array of StatusCode
DiagnosticInfos	Array of DiagnosticInfo

ReadEventHistoryRequest

Used when reading event history.

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
StartTime	DateTime	The start time of the query
EndTime	DateTime	The end time of the query
Fields	Array of String	The event fields to include in the response
WhereClause	SimpleWhereClause	The where clause used in the query
ReadValueIds	Array of HistoryReadValueId	The nodes to read events history for
Limit	Limit	Limit the number of events returned from the request

SimpleWhereClause

Represents a where clause in an event history query.

Members	Data type	Description	Default value
EventTypeNodedId	NodeId	The node id of the event type of the events which shall be returned in the response. If null BaseEventType (i.e. all events) is used.	null
AndWhere	Array of SimpleExpression	A list of expressions which must all be true for the event to be returned.

SimpleExpression

Represents a logical expression used in an event history query.

Members	Data type	Description	Default value
Field	String	The node id of the event type of the events which shall be returned in the response. If null BaseEventType (i.e. all events) is used.	null
Op	Int32	The operator in the expression. See FilterOperator for options
Value	Variant	The value which the field is compared against.

ReadEventHistoryResponse

Response when reading event history.

Members	Data type	Description	Default value
Success	Boolean	False if no values were read.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
EventsResult	Array of HistoryEventResult	An array of events

HistoryEventResult

Members	Data type	Description	Default value
NodeId	NodeId	The node id of the Request .
StatusCode	StatusCode	The status of the query for this node.
HistoryEvents	Array of EventMessage	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null

EventMessage

Represents a single event. The fields may not be present if the Request does not include the field.

Members	Data type	Description	Default value
Time	DateTime	The time of the event.	null
Message	String	The message of the event.	null
SourceName	String	The name of the source where the event occurred.	null
EventType	NodeId	The node id of the event type of the event.	null
Severity	Int32	The severity of the event. The higher the value the more severe the event.	null
SourceNode	NodeId	The node id of the source where the event occurred.	null
ReceiveTime	DateTime		null
ActiveTime	DateTime		null
BranchId	NodeId		null
ClientUserId	String	The id of the user attached with the event for instance through an acknowledge	null
Active	Boolean	Indicates whether the event was active.	null
Acknowledged	Boolean	Indicates whether the event was acknowleged.	null
Enabled	Boolean	Indicates whether the event was enabled.	null
Confirmed	Boolean	Indicates whether the event was confirmed.	null
ConditionClassId	NodeId		null
ConditionClassName	String		null
ConditionName	String	The name of the condition if the event is of ConditionType	null
ConditionSubClassId	NodeId		null
ConditionSubClassName	String		null
Comment	String	Comment attached to the event	null
Quality	StatusCode		null
EventTypeName	String	The name of the event type this event belongs to	null
QualityText	String	The quality represented as text	null

WriteEventHistoryRequest

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
Updates	Array of EventHistoryUpdate	The connection info.

EventHistoryUpdate

Members	Data type	Description	Default value
NodeId	NodeId	TODO	null
PerformInsertReplace	PerformUpdateType	TODO	null
Fields	Array of String	The fields to write	null
WhereClause	SimpleWhereClause	The where clause	null
Events	Array of EventMessage	The events to write	null

WriteEventHistoryResponse

Members	Data type	Description	Default value
Success	Boolean	False if no values were read.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
HistoryUpdateResults	Array of HistoryUpdateResult	The results of the write operation.

ReadEventHistoryExtendedRequest

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
StartTime	DateTime	The start time of the query
EndTime	DateTime	The end time of the query
Filter	EventFilter	The filter of the query. Decides which fields are returned, and the condition for returning an event.
ReadValueIds	Array of HistoryReadValueId	The nodes to read events history for
Limit	Limit	Limit the number of events returned from the request

ReadEventHistoryExtendedResponse

Members	Data type	Description	Default value
Success	Boolean	False if no values were read.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
EventsResult	Array of HistoryEventExtendedResult	The result of the read operation

HistoryEventExtendedResult

Members	Data type	Description
NodeId	NodeId	The node id of the Request .
StatusCode	StatusCode	The status of the query for this node.
HistoryEvents	Array of HistoryEventFieldList	An array of events

HistoryEventFieldList

Members	Data type	Description	Default value
EventFields	Array of Variant	The values of the event. The index of the collection corresponds to the index of the select clause in the query.

WriteEventHistoryExtendedRequest

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
UpdateEventDetails	Array of UpdateEventDetails	The events to write

WriteEventHistoryExtendedResponse

Members	Data type	Description	Default value
Success	Boolean	False if no values were read.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
HistoryUpdateResults	Array of HistoryUpdateResult	The results of the write operation.

EventFieldDefinition

Represents a predefined event field.

Members	Data type	Description
Name	String	The name of the event field.
EventTypeId	NodeId	The node id of the event type this field belongs to.
BrowsePath	String	The browse path of the field.
AttributeId	UInt32	The attribute id of the event field.

GetEventTypesRequest

Used when getting event types.

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
BaseEventType	NodeId	The event type to get the inherited event types from.	null means the BaseEventType (Node Id: 2041).
Recursive	Boolean	Gets all inherited event types recursively.	True.
IncludeBaseEventTypeInResponse	Boolean	Gets event type information of BaseEventType.	True.

GetEventTypesResponse

The response when getting event types.

Members	Data type	Description	Default value
Success	Boolean	False if no values were read.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
EventTypes	Array of EventType	Contains the event types

EventType

Members	Data type	Description
BrowseName	QualifiedName	The qualified name of the event type.
DisplayName	String	The display name of the event type.
NodeId	NodeId	The node id of the event type.

AddCommentRequest

This is used when adding a comment to an event.

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
ObjectId	NodeId		null
EventId	String	The id of the event. See EventMessage	null
Message	LocalizedText	The comment	null

AddCommentResponse

The response when adding a comment.

Members	Data type	Description	Default value
Success	Boolean	True if operation was successful.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
StatusCode	StatusCode	Contains status code of the add comment operation.

ConfirmRequest

This is used when confirming an event.

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
ObjectId	NodeId		null
EventId	String	The id of the event. See EventMessage	null
Message	LocalizedText	The comment	null

ConfirmResponse

The response when confirming an event.

Members	Data type	Description	Default value
Success	Boolean	True if operation was successful.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
StatusCode	StatusCode	Contains status code of the confirm operation.

AcknowledgeRequest

This is used when acknowledging an event.

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
ObjectId	NodeId		null
EventId	String	The id of the event. See EventMessage	null
Message	LocalizedText	The comment	null

AcknowledgeResponse

The response when acknowledging an event.

Members	Data type	Description	Default value
Success	Boolean	True if operation was successful.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
StatusCode	StatusCode	Contains status code of the acknowledge operation.

CreateEventSubscriptionRequest

This is used when creating a subscription for events.

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
SourceNodeId	NodeId	The id of the node from where the events must occur. This includes nodes "below" this node in the hierarchy.
DisplayName	String		null
PublishingInterval	Int32	This interval defines the cyclic rate that the Subscription is being requested to return Notifications to the Client. This interval is expressed in milliseconds.	100
KeepAliveCount	UInt32	Requested lifetime count. The lifetime count shall be a minimum of three times the keep keep-alive count. When the publishing timer has expired this number of times without a Publish request being available to send a NotificationMessage, then the Subscription shall be deleted by the Server.	100
LifetimeCount	UInt32	Requested maximum keep-alive count. When the publishing timer has expired this number of times without requiring any NotificationMessage to be sent, the Subscription sends a keep-alive Message to the Client.	100
MaxNotificationsPerPublish	UInt32	The maximum number of notifications that the Client wishes to receive in a single Publish response. A value of zero indicates that there is no limit.	1000
Fields	Array of String	The fields to be returned when an event occurs
WhereClause	SimpleWhereClause	The condition that must be met for an event to be returned.

CreateEventSubscriptionResponse

The response when creating an event.

Members	Data type	Description	Default value
Success	Boolean	True if subscription was created.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
SubscriptionId	String	If success this string contains the subscription id.

EventsChangedResponse

The response when an event occurs.

Members	Data type	Description	Default value
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
SubscriptionId	String	The id of the subscription.
Events	Array of EventMessage	The events.

CloseEventSubscriptionRequest

This is used when closing a subscription for events.

Members	Data type	Description	Default value
Connection	Connection	The connection info.
SubscriptionId	String	The id of the subscription to close.

CloseEventSubscriptionResponse

The response when closing an event subscription.

Members	Data type	Description
Success	Boolean	True if subscription was closed successfully.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
SubscriptionId	String	The id of the subscription.

CreateDataValueSubscriptionRequest

This is used when creating a data value subscription

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
DisplayName	String
PublishingInterval	Int32	This interval defines the cyclic rate that the Subscription is being requested to return Notifications to the Client. This interval is expressed in milliseconds.
KeepAliveCount	UInt32	Requested lifetime count. The lifetime count shall be a minimum of three times the keep keep-alive count. When the publishing timer has expired this number of times without a Publish request being available to send a NotificationMessage, then the Subscription shall be deleted by the Server.
LifetimeCount	UInt32	Requested maximum keep-alive count. When the publishing timer has expired this number of times without requiring any NotificationMessage to be sent, the Subscription sends a keep-alive Message to the Client.
MaxNotificationsPerPublish	UInt32	The maximum number of notifications that the Client wishes to receive in a single Publish response. A value of zero indicates that there is no limit.
Nodes	Array of DataValueMonitoredItem	The nodes to subscribe to

DataValueMonitoredItem

This data type contains information regarding subscription of an item. The ClientHandle must set to a unique string for each node.

Members	Data type	Description	Default value
NodeId	NodeId	The id of the node to subscribe to.
IndexRange	string		null
SamplingInterval	Int32		null
QueueSize	UInt32		null
DiscardOldest	Boolean		null
RelativePath	String		null
DataChangeFilter	DataChangeFilter		null
ClientHandle	string		Id representing this node.

DataChangeFilter

This filter decides when a data value is deemed to have changed.

Members	Data type	Description
Trigger	Int32	Decides when to trigger an data value changed event. See DataChangeTrigger
DeadbandType	UInt32	Decides which kind of dead band check to use. See DeadbandType
DeadbandValue	Double	The dead band value.

CreateDataValueSubscriptionResponse

The response when querying for namespaces.

Members	Data type	Description	Default value
Success	Boolean	True if subscription was created successfully.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
SubscriptionId	String	If success: the subscription id.

DataValuesChangedResponse

When data values have changed this is sent to the subscriber.

Members	Data type	Description
ServerNamespaces	Array of String	Contains the namespaces on the server.
SubscriptionId	String	The subscription id.
Values	Array of NodeIdDataValue	The subscribed values which have changed.

NodeIdDataValue

Represents a change value. The ClientHandle corresponds to the ClientHandle in DataValueMonitoredItem.

Members	Data type	Description	Default value
ClientHandle	string	The handle given in DataValueMonitoredItem.
Value	Variant	The actual data value
StatusCode	StatusCode	The status code
SourceTimestamp	DateTime
SourcePicoseconds	Numeric		0
ServerTimestamp	DateTime
ServerPicoseconds	Numeric		0

CloseDataValueSubscriptionRequest

This is used when a data value subscription shall be closed.

Members	Data type	Description	Default value
Connection	Connection	The connection info.
SubscriptionId	String	The subscription id.

CloseDataValueSubscriptionResponse

Returend when data value subscription has been called.

Members	Data type	Description
Success	Boolean	True if closed successfully.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.
SubscriptionId	String	The subscription id.

StartDataValueSubscriptionResponse

Returned when data value subscription has been started.

Members	Data type	Description
Success	Boolean	True if closed successfully.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.

NamespacesRequest

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.

NamespaceResponse

The response when querying for namespaces.

Members	Data type	Description
Success	Boolean	True if namespaces were read successfully.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
Namespaces	Array of String	The namespaces in the OPC UA server.

BrowseRequest

This is used when browsing for nodes.

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
View	ViewDescription	The view to browse. Is usually null.	null
NodeToBrowse	NodeId	The id of the node to browse.
BrowseDirection	Int32	The direction to browse. See BrowseDirection
ReferenceTypeId	NodeId	The reference types to follow.
IncludeSubtypes	Boolean	Include sub types of the specified ReferenceTypeId.
NodeClassMask	UInt32	A mask indicating what kind of nodes to browse for. The node classes can be OR'ed'

BrowseMultiRequest

This is used when browsing for nodes.

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
View	ViewDescription	The view to browse. Is usually null.	null
Nodes	Array of BrowseNodes	The nodes to browse.

BrowseNodes

Members	Data type	Description
NodeToBrowse	NodeId	The id of the node to browse.
BrowseDirection	Int32	The direction to browse. See BrowseDirection
ReferenceTypeId	NodeId	The reference types to follow.
IncludeSubtypes	Boolean	Include sub types of the specified ReferenceTypeId.
NodeClassMask	UInt32	A mask indicating what kind of nodes to browse for. The node classes can be OR'ed'

BrowseResponse

The response after a Browse, BrowseNext or GetChildren call.

Members	Data type	Description	Default value
Success	Boolean	False if browse was unsuccesful.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
BrowseResult	BrowseResult	The result of a browse call

BrowseResult

Members	Data type	Description	Default value
References	Array of ReferenceDescription	The references found.
StatusCode	StatusCode	The status code of the browse.

MultiBrowseResponse

The response after a BrowseMulti, BrowsePropertiesMulti call.

Members	Data type	Description	Default value
Success	Boolean	False if browse was unsuccesful.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
BrowseResults	Array of BrowseResult	The result of a browse call

ChildrenRequest

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
Parent	NodeId	The parent for which we want to browse for children.

BrowsePropertiesRequest

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
NodeId	NodeId	The node for which we want to browse for properties.

BrowsePropertiesMultiRequest

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
NodeIds	Array of NodeId	The nodes for which we want to browse for properties.

TranslateBrowsePathsRequest

Members	Data type	Description	Default value
ClientNamespaces	Array of String	Contains the namespaces the client uses.	null
Connection	Connection	The connection info.
BrowsePaths	Array of QualifiedNamePath	The browse paths to find node ids for.

QualifiedNamePath

Members	Data type	Description	Default value
StartingNode	NodeId	The node id of the starting node of the relative path.	null
RelativePath	Array of QualifiedName	The relative path described by browse names.

TranslateBrowsePathsResponse

Members	Data type	Description	Default value
Success	Boolean	False if browse was unsuccesful.
ErrorMessage	String	Only present if Success is false, and contains error message.
ErrorCode	Int32	Only present if Success is false, and contains the error code.
ServerNamespaces	Array of String	Contains the namespaces on the server.	null if the corresponding request's' ClientNamespaces was null
BrowsePathResults	Array of BrowsePathResult	Contains the node ids of the browse path request

BrowsePathResult

Members	Data type	Description	Default value
StatusCode	StatusCode	Indicating whether the request was successful
Targets	Array of BrowsePathTarget	The targets of the browse paths.

BrowsePathTarget

Members	Data type	Description	Default value
TargetId	ExpandedNodeId	The node id of the target
RemainingPathIndex	UInt32	The index of the first unprocessed element in the RelativePath. This value shall be equal to the maximum value of Index data type if all elements were processed .

EventFilter

Members	Data type	Description	Default value
SelectClauses	Array of SimpleAttributeOperand	Fields to be selected
WhereClause	ContentFilter	The condition an event must meet to be returned in a query.

SimpleAttributeOperand

Members	Data type	Description	Default value
TypeDefinitionId	NodeId	The event type id.
BrowsePath	Array of QualifiedName	The browsepath for the field.
AttributeId	UInt32	The attribute id of value of the field.
IndexRange	string	The index range of the value.	null

ContentFilter

From the OPC Foundation's OPC UA specification:

The ContentFilter structure defines a collection of elements that define filtering criteria. Each element in the collection describes an operator and an array of operands to be used by the operator. The operators that can be used in a ContentFilter are described in FilterOperator. The filter is evaluated by evaluating the first entry in the element array starting with the first operand in the operand array. The operands of an element may contain References to sub-elements resulting in the evaluation continuing to the referenced elements in the element array. The evaluation shall not introduce loops. For example evaluation starting from element A shall never be able to return to element A. However there may be more than one path leading to another element B.If an element cannot be traced back to the starting element it is ignored. Extra operands for any operator will result in an error.

Members	Data type	Description	Default value
Elements	Array of ContentFilterElement	An array of content filter elements making up the where clause.

ContentFilterElement

Members	Data type	Description	Default value
FilterOperator	FilterOperator	The filter operator.
FilterOperands	Array of ExtensionObject	The operands in the filter expression.

OPC UA Data types

ByteString

ByteString is a sequence of bytes.
A ByteString is represented by a base64 encoded string in JavaScript.

XmlElement

Represents an XML element.
Not supported

NodeId

The NodeId data type represents an OPC UA Node.

Members	Data type	Description	Default value
Id	Numeric, String, Guid, Opaque	The id of the node
IdType	UInt16	The id type of the node. Numeric = 0, String = 1, Guid = 2, Opaque = 3	0
Namespace	UInt16	The namspace index of the namespace the node id belongs to	0

JSON Examples

Below are listed some JSON examples and the corresponding values.

IdType	Id	Namespace	Json
0	45345	0	{"Id":45345}
1	"idxyz"	0	{"IdType":1,"Id":"idxyz"}
2	"f114f6cf-31e0-43c8-9c22-399570312496"	0	{"IdType":2,"Id":"f114f6cf-31e0-43c8-9c22-399570312496"}
3	"IB8eHRwbGhkYFxYVFBMSERAPDg0MCwoJCAcGBQQDAgE="	0	{"IdType":3,"Id":"IB8eHRwbGhkYFxYVFBMSERAPDg0MCwoJCAcGBQQDAgE="}
1	"ixyz"	3	{"IdType":1,"Id":"idxyz","Namespace":3}

ExpandedNodeId

A node id that stores the namespace URI instead of the namespace index.
TODO: Add

StatusCode

A StatusCode in OPC UA is numerical value that is used to report the outcome of an operation performed by an OPC UA Server. The StatusCode is a 32-bit unsigned integer. The top 16 bits represent the numeric value of the code that shall be used for detecting specific errors or conditions. The bottom 16 bits are bit flags that contain additional information but do not affect the meaning of the StatusCode.

See Status codes for possible status codes.

Members	Data type	Description	Default value
Code	UInt32	The status code
Symbol	String	The textual representation

JSON Examples

Code	Json
0	{}
2147483648	{"Code":2147483648,"Symbol":"Bad"}

QualifiedName

A string qualified with a namespace.

Members	Data type	Description	Default value
Name	String	The text portion of the QualifiedName
Uri	UInt16	Index that identifies the namespace that defines the name.	0

JSON Examples

Name	Uri	Json
"Valve1"	0	{"Name":"Valve1"}
"Valve2"	4	{"Name":"Valve2","Uri":4}

LocalizedText

A localized text string with a locale identifier

Members	Data type	Description	Default value
Text	String	The text
Locale	String	The locale for the localized text.	""

JSON Examples

Text	Locale	Json
"mytext"		{"Text":"mytext"}
"Valve2"	"nb-NO"	{"Text":"mytext","Locale":"nb-NO"}

ExtensionObject

An opaque object with a syntax that may be unknown to the receiver Not supported

DiagnosticInfo

A diagnostic information associated with a result code

Members	Data type	Description	Default value
SymbolicId	Int32	The index of the symbolic id in the string table.
NamespaceUri	Int32	The index of the namespace uri in the string table.	""
Locale	Int32	The index of the locale associated with the localized text.	""
LocalizedText	Int32	The index of the localized text in the string table.	""
AdditionalInfo	String	The additional debugging or trace information.	""
InnerStatusCode	StatusCode	The status code returned from an underlying system.	""
InnerDiagnosticInfo	DiagnosticInfo	The diagnostic info returned from a underlying system.	""

Limit

The Limit data type defines the structure to limit the request to a certain number of values.

Members	Data type	Description	Default value
StartIndex	Int32	The index from where to return elements
NumRecords	UInt16	THe number of elements to return

ReadValueId

The ReadValueId data type is used when reading attributes.

Members	Data type	Description	Default value
NodeId	NodeId	The node id to read
AttributeId	UInt32	The id of the attribute to read
IndexRange	String		null

JSON Examples

{"NodeId":{"IdType":1,"Id":"idxyz","Namespace":3},"AttributeId":13}

Variant

The variant represents a value. The value can be of a number of data types. The variant will be serialized differently depending on the actual data type it represents.
The different data types which can be represented by a variant is listed below.

Id	Name	Description
0	Null	An invalid or unspecified value.
1	Boolean	A boolean logic value (true or false)
2	SByte	An 8 bit signed integer value.
3	Byte	An 8 bit unsigned integer value.
4	Int16	A 16 bit signed integer value
5	UInt16	A 16 bit unsigned integer value
6	Int32	A 32 bit signed integer value
7	UInt32	A 32 bit unsigned integer value
8	Int64	A 64 bit signed integer value
9	UInt64	A 64 bit unsigned integer value
10	Float	An IEEE single precision (32 bit) floating point value
11	Double	An IEEE double precision (64 bit) floating point value
12	String	A sequence of Unicode characters
13	DateTime	An instance in time
14	Guid	A 128-bit globally unique identifier
15	ByteString	A sequence of bytes
16	XmlElement	An XML element
17	NodeId	An identifier for a node in the address space of a UA server
18	ExpandedNodeId	A node id that stores the namespace URI instead of the namespace index
19	StatusCode	A structured result code
20	QualifiedName	A string qualified with a namespace
21	LocalizedText	A localized text string with an locale identifier
22	ExtensionObject	An opaque object with a syntax that may be unknown to the receiver
23	DataValue	A data value with an associated quality and timestamp
24	Variant	Any of the other built-in types
25	DiagnosticInfo	A diagnostic information associated with a result code

The JavaScript data structure will look like this:

Members	Data type	Description	Default value
Type	Byte	The Variant type (Id)
Body	Any	Depends on the Type

JSON Examples

Type	Value	Json
Float (10)	87.34	{"Type":10,"Body":87.34}
Guid (14)	f114f6cf-31e0-43c8-9c22-399570312496	{"Type":14,"Body":"f114f6cf-31e0-43c8-9c22-399570312496"}

DataValue

The data value is returned when reading an attribute.

Members	Data type	Description	Default value
Value	Variant	The actual data value
StatusCode	StatusCode	The status code
SourceTimestamp	DateTime
SourcePicoseconds	Numeric		0
ServerTimestamp	DateTime
ServerPicoseconds	Numeric		0

WriteValue

The write value is used when writing an attribute.

Members	Data type	Description
NodeId	NodeId	The node id
AttributeId	Int32	The attribute id
Value	DataValue	The value to be written

JSON Examples

{"NodeId":{"IdType":1,"Id":"V|Worker.Write","Namespace":2},"AttributeId":13,"Value":{"Value":{"Type":8,"Body":"637709221331900544"}}}

ReferenceDescription

Members	Data type	Description
NodeId	NodeId	The node id of the reference
IsForward	Boolean	True if forward reference
Value	DataValue	The value to be written
ReferenceTypeId	NodeId	The node id of the reference type
BrowseName	QualifiedName	The browse name of the referenced node
DisplayName	LocalizedText	The display name of the referenced node
NodeClass	NodeClass	The node class of the referenced node
TypeDefinition	NodeId	The node id of the type definition of the reference node

FilterOperator

The list below contains all the available filter operators used in SimpleExpression.

Note that not all of the operators make sense in a SimpleExpression.

Description	Value
Equals	0
IsNull	1
GreaterThan	2
LessThan	3
GreaterThanOrEqual	4
LessThanOrEqual	5
Like	6
Not	7
Between	8
InList	9
And	10
Or	11
Cast	12
InView	13
OfType	14
RelatedTo	15
BitwiseAnd	16
BitwiseOr	17

TimestampsToReturn

This int can be 4 values:

Description	Value
Return the source timestamp	0
Return the Server timestamp	1
Return both the source and Server timestamps	2
Return neither timestamp	3

BrowseDirection

This int can be 3 values:

Description	Value
Forward	0
Inverse	1
Both	2

NodeClass

A node class is represented by an int:

Description	Value
Object	1
Variable	2
Method	4
ObjectType	8
VariableType	16
ReferenceType	32
DataType	64
View	128

DataChangeTrigger

Description	Value
Status	0
StatusValue	1
StatusValueTimestamp	2

DeadbandType

Description	Value
None	0
Absolute	1
Percent	2

PerformUpdateType

Description	Value
Insert	1
Replace	2
Update	3
Remove	4

2021-11-11T16:00:00Z

OPC UA Values REST API