This Method provides the capability to persistently add a link to an externally managed resource by adding a Variable according to the input arguments with a HasComponent Reference to the Object the Method is called on. The server shall manage the added link persistently, i.e., if the Method was executed successful, the Variable representing the link shall be persistent and available after restart of the Server. It might disappear after resetting or reconfiguring the Server or after calling the RemoveLink Method. The Value Attribute of the created Node should be writable, so the end-user can change the URI. In addition, the BrowseName, DisplayName, and Description might be writable. Servers might restrict the execution of this Method as well as writing the Attributes to specific users / roles.

The signature of this Method is specified below. Table 31 and Table 32 specify the Arguments and AddressSpace representation, respectively.

Signature

AddLink (

[in] 0:UriString LinkToExternalSource,

[in] 0:QualifiedName BrowseName,

[in] 0:LocalizedText DisplayName,

[in] 0:LocalizedText Description,

[out] 0:NodeId LinkVariable);

Table 31 – AddLink Method Arguments

Argument

Description

LinkToExternalSource

Link to an external source. The server might or might not check if a correct URI is provided, or if the URI is available/reachable.

BrowseName

The BrowseName of the new created Node. Method fails if a Variable with the same BrowseName already exists.

DisplayName

The DisplayName of the new created Node. If the server supports multiple locales, and the Client wants to provide more than one locale, the Write operation on the Variable shall be used.

Description

The Description of the new created Node. If the server supports multiple locales, and the Client wants to provide more than one locale, the Write operation on the Variable shall be used.

LinkVariable

The NodeId of the newly created Variable.

Method Result Codes (defined in Call Service)

Result Code

Description

Bad_UserAccessDenied

See OPC 10000-4 for a general description.

Bad_InvalidArgument

See OPC 10000-4 for a general description.

Table 32 – AddLink Method AddressSpace definition

Attribute

Value

BrowseName

AddLink

References

NodeClass

BrowseName

DataType

TypeDefinition

ModellingRule

0:HasProperty

Variable

0:InputArguments

0:Argument[]

0:PropertyType

0:Mandatory

0:HasProperty

Variable

0:OutputArguments

0:Argument[]

0:PropertyType

0:Mandatory

Conformance Units

AMB DocumentationLinks Base