UA Part 4: Services - 5.7.3 AddReferences

This Serviceis used to add one or more Referencesto one or more Nodes. The NodeClassis an input parameter that is used to validate that the Referenceto be added matches the NodeClassof the TargetNode. This parameter is not validated if the Referencerefers to a TargetNodein a remote Server.

In certain cases, adding new Referencesto the AddressSpaceshall require that the Serveradd new Serverids to the Server’s ServerArray Variable. For this reason, remote Serversare identified by their URI and not by their ServerArrayindex. This allows the Serverto add the remote ServerURIs to its ServerArray.

5.7.3.2 Parameters

Table 25defines the parameters for the Service.

Table 25– AddReferences Service Parameters

Name	Type	Description
Request
requestHeader	Request Header	Common request parameters (see 7.33for RequestHeaderdefinition).
referencesToAdd []	AddReferences Item	List of Referenceinstances to add to the SourceNode. The targetNodeClassof each Referencein the list shall match the NodeClassof the TargetNode. This structure is defined in-line with the following indented items.
sourceNodeId	NodeId	NodeIdof the Nodeto which the Referenceis to be added. The source Nodeshall always exist in the Serverto add the Reference. The isForward parameter can be set to FALSE if the target Nodeis on the local Serverand the source Nodeon the remote Server.
referenceTypeId	NodeId	NodeIdof the ReferenceTypethat defines the Reference.
isForward	Boolean	If the value is TRUE, the Servercreates a forward Reference. If the value is FALSE, the Servercreates an inverse Reference.
targetServerUri	String	URI of the remote Server. If this parameter is not null or empty, it overrides the serverIndexin the targetNodeId.
targetNodeId	Expanded NodeId	Expanded NodeIdof the TargetNode. The ExpandedNodeIdtype is defined in 7.16.
targetNodeClass	NodeClass	NodeClassof the TargetNode. The Clientshall specify this since the TargetNodemight not be accessible directly by the Server.

Response
responseHeader	Response Header	Common response parameters (see 7.34for ResponseHeaderdefinition).
results []	StatusCode	List of StatusCodesfor the Referencesto add (see 7.39for StatusCodedefinition). The size and order of the list matches the size and order of the referencesToAddrequest parameter.
diagnosticInfos []	Diagnostic Info	List of diagnostic information for the Referencesto add (see 7.12for DiagnosticInfo definition). The size and order of the list matches the size and order of the referencesToAddrequest parameter. This list is empty if diagnostics information was not requested in the request header or if no diagnostic information was encountered in processing of the request.

5.7.3.3 Service results

Table 26defines the Serviceresults specific to this Service. Common StatusCodesare defined in Table 182.

Table 26– AddReferences Service Result Codes

Symbolic Id	Description
Bad_NothingToDo	See Table 182for the description of this result code.
Bad_TooManyOperations	See Table 182for the description of this result code.

5.7.3.4 StatusCodes

Table 27defines values for the resultsparameter that are specific to this Service. Common StatusCodesare defined in Table 183.

Table 27– AddReferences Operation Level Result Codes

Symbolic Id	Description
Bad_SourceNodeIdInvalid	See Table 183for the description of this result code.
Bad_ReferenceTypeIdInvalid	See Table 183for the description of this result code.
Bad_ServerUriInvalid	See Table 182for the description of this result code.
Bad_TargetNodeIdInvalid	See Table 183for the description of this result code.
Bad_NodeClassInvalid	See Table 183for the description of this result code.
Bad_ReferenceNotAllowed	The reference could not be created because it violates constraints imposed by the data model on this Server.
Bad_ReferenceLocalOnly	The reference type is not valid for a reference to a remote Server.
Bad_UserAccessDenied	See Table 182for the description of this result code.
Bad_DuplicateReferenceNotAllowed	The reference type between the nodes is already defined.
Bad_InvalidSelfReference	The Serverdoes not allow this type of self reference on this node.