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ObjectTypes

objectTypes:
  - browseName: MySensorType
    components:
    properties:
    organizes:
    methods:

browseName​

  • The browse name is a normative name for the OPCUA node it represents, and must be chosen with care. Indeed, the browseName is used by OPCUA clients to browse the tree of nodes by their access path. The path of a node in the tree is made of browseNames.

  • We will follow the naming style already used by companion standards such as Device Integration, Analyser Device Integration, Robotics etc. which are referenced to ensure a uniform style.

  • It is commonly accepted that the BrowseName should be a term expressed in 'English' to allow for internationalization of the API.

  • The use of acronyms or abbreviations should be avoided and the use of an explicit term or combination of terms should be preferred

  • The use of the naming convention called "PascalCase" is strongly recommended. The first letter of the name starts with a capital letter, in case of a compound name (e.g. Adjective+Name), the two terms are pasted without space and each term starts with a capital letter.

  • In practice, it consists of alpha numeric characters. A browse name must not start with a number.

  • For Instance

    • ❌ capteur_de_temperature (incorrect because it contains French terms, does not use PascalCase)
    • ❌ temperatureSensor (incorrect because of or spaces in the name)
    • ✅ TemperatureSensor (correct because terms in English according to convention)

subtypeOf​

  • subtypeOf specifies the ObjectType from which the new ObjectType is derived. If ommitted, the modeler assume that the object type derives from BaseObjectType in the ua namespace.
objectTypes:
  - browseName: MySensorType
    subtypeOf: di:DeviceType

Components​

Properties​

Methods​

Example:

# yaml-language-server: $schema=../../schemas/nodeset2.schema.json
namespaceUri: http://sterfive.com/UA/test/
objects:
 -  browseName: Calculator
    organizedBy: /ua:Objects
    methods:
       - browseName: AddTwoValues
         inputArguments:
          - name: Operand2
            dataType: ua:Double
            description: La valeur de l'opérande 1
          - name: Operand1
            dataType: ua:Double
         outputArguments:
           - name: Result
             dataType: ua:Double

Click here to see the generated XML File
<UAObject NodeId="ns=1;i=1000" BrowseName="1:Calculator">
        <DisplayName>Calculator</DisplayName>
        <References>
            <Reference ReferenceType="HasTypeDefinition">i=58</Reference>
            <Reference ReferenceType="Organizes" IsForward="false">i=85</Reference>
            <Reference ReferenceType="HasComponent">ns=1;i=1001</Reference>
        </References>
    </UAObject>
    <UAMethod NodeId="ns=1;i=1001" BrowseName="1:AddTwoValues" ParentNodeId="ns=1;i=1000">
        <DisplayName>AddTwoValues</DisplayName>
        <References>
            <Reference ReferenceType="HasProperty">ns=1;i=1002</Reference>
            <Reference ReferenceType="HasProperty">ns=1;i=1003</Reference>
        </References>
    </UAMethod>
    <UAVariable NodeId="ns=1;i=1002" BrowseName="InputArguments" ParentNodeId="ns=1;i=1001" ValueRank="1" ArrayDimensions="2" DataType="Argument">
        <DisplayName>InputArguments</DisplayName>
        <Description>the definition of the input argument of method 1:Calculator.1:AddTwoValues</Description>
        <References>
            <Reference ReferenceType="HasTypeDefinition">i=68</Reference>
            <Reference ReferenceType="HasModellingRule">i=78</Reference>
        </References>
        <Value>
            <ListOfExtensionObject xmlns="http://opcfoundation.org/UA/2008/02/Types.xsd">
                <ExtensionObject>
                    <TypeId>
                        <Identifier>i=297</Identifier>
                    </TypeId>
                    <Body>
                        <Argument>
                            <Name>Operand2</Name>
                            <DataType>
                                <Identifier>i=11</Identifier>
                            </DataType>
                            <ValueRank>-1</ValueRank>
                            <ArrayDimensions/>
                            <Description>
                                <Text/>
                            </Description>
                        </Argument>
                    </Body>
                </ExtensionObject>
                <ExtensionObject>
                    <TypeId>
                        <Identifier>i=297</Identifier>
                    </TypeId>
                    <Body>
                        <Argument>
                            <Name>Operand1</Name>
                            <DataType>
                                <Identifier>i=11</Identifier>
                            </DataType>
                            <ValueRank>-1</ValueRank>
                            <ArrayDimensions/>
                            <Description>
                                <Text/>
                            </Description>
                        </Argument>
                    </Body>
                </ExtensionObject>
            </ListOfExtensionObject>
        </Value>
    </UAVariable>
    <UAVariable NodeId="ns=1;i=1003" BrowseName="OutputArguments" ParentNodeId="ns=1;i=1001" ValueRank="1" ArrayDimensions="1" DataType="Argument">
        <DisplayName>OutputArguments</DisplayName>
        <Description>the definition of the output arguments of method 1:Calculator.1:AddTwoValues</Description>
        <References>
            <Reference ReferenceType="HasTypeDefinition">i=68</Reference>
            <Reference ReferenceType="HasModellingRule">i=78</Reference>
        </References>
        <Value>
            <ListOfExtensionObject xmlns="http://opcfoundation.org/UA/2008/02/Types.xsd">
                <ExtensionObject>
                    <TypeId>
                        <Identifier>i=297</Identifier>
                    </TypeId>
                    <Body>
                        <Argument>
                            <Name>Result</Name>
                            <DataType>
                                <Identifier>i=11</Identifier>
                            </DataType>
                            <ValueRank>-1</ValueRank>
                            <ArrayDimensions/>
                            <Description>
                                <Text/>
                            </Description>
                        </Argument>
                    </Body>
                </ExtensionObject>
            </ListOfExtensionObject>
        </Value>
    </UAVariable>
  • inputArguments describes the input arguments of the method.
  • name contains the name of the argument. We use the PascalCase convention and a universal name
  • dataType refers to the data type of the argument. The dataType contains the name of the data type. If this data type is not defined in this YML document, we precede the name with the namespace alias with a colon. For example:
    • ua:Double: refers to the "Double" dataType defined in the ua namespace (the standard OPCUA namespace)
    • di:DeviceHealthEnumeration refers to the DataType "DeviceHealthEnumeration" defined in the namespace whose alias is di (i.e. the namespace Device Integration whose uri is http://opcfoundation.org/UA/DI/ )

conventions​

modelingRule by défaut​

  • components and features added to an ObjectType or VariableType have a modellingRule: Mandatory by default. You must explicitly add modellingRule: Optional to make it optional.

overloading of optional components or properties​

It is sometimes necessary to make mandatory a component that is marked as optional in the base ObjectType. To do this, we redefine

For example, the ParamerSet function group defined in the DeviceType ObjectType of the di namespace is optional and needs to be made mandatory in your derived type because it will be enriched with variable parameters specific to your device.

namespaces:
  - di
objectTypes:
  - browseName: MySensorDeviceType
    subtypeOf: di:DeviceType
    components:
      # le composant ParameterSet defini dans di:DeviceType est redéfini et rendu obligatoire
      # dans MySensorDeviceType
      - browseName: di:ParameterSet 
        components:
          - browseName: Temperature
            dataType: ua:Double

Note:

  • be sure to put the overloaded property or component in the correct components:, properties: or methods: category
  • the browseName of the overloaded property or component must be expressed in the same namespace as in the Base Type. Don't forget to prefix the browseName with the corresponding namespace alias.

how to know the structure of a basic type​

We recommand that you consult the PDF documentation associated with the imported models to understand the structure of the Types you wish to use in your model.

You can also resort to exploring the types in the OPC UA tree with an OPCUA client. This technique is also very efficient but requires some practice.