Call for READ operations (the name READ is the arbitrarily chosen name for this call)
Input Parameter
For the READ Connector Call, you need to configure the “operationType ” and the “nodeId“(consisting of 2 mandatory parameters: “identifier” and “namespaceIndex” and one optional parameter: “identifierType”). Furthermore, you can define the “order” of the operations in the code (optional).
operationType: Defines which operation you want to execute, in this case, “READ”.
Parameter Name: operations[0]/operationType
Constant Value: READ
Data Type: String
nodeId: Defines the identification of the OPC/UA node. It is split in 3 parameters (two mandatory and one optional):
- identifier:
Parameter Name: operations[0]/nodeId/identifier
Data Type: String - namespaceIndex:
Parameter Name: operations[0]/nodeId/namespaceIndex
Data Type: String
Possible Values: All numbers from 0 to 65535. - identifierType (optional): Searches for the Identifier with a fixed Data Type.
Parameter Name: operations[0]/identifierType
Data Type: String
Constant Value: Numeric, UUID, String, Byte String
Note: In every namespace, each ID must be unique for its own identifierType (it is possible to use the String “7617” and the Numeric 7167 together in one namespace)
order (optional): Order in which the actions should be performed.
This parameter changes the execution order of the specified READ commands e.g. if we have three READ commands. Command 1 reads from node x, command 2 reads from node y and command 3 from node z, the normal execution order would be: x, y, z.
By specifying the read order with numbers starting from 0 to the last command number subtracted by one (e.g. for three commands it would be 2), the execution will be changed according to the defined number.
For example, by adding “order”:[2,1,0] to your code, you switched the operations, so the read commands would be executed the following way. z, x, y.
Batch Operations
It is possible to execute multiple different OPC/UA Operations with one connector call. In order to do that, the number in the operations[X] path must be used. Each number represents one OPC/UA Operation.
A batch call with two READ-Operations would look as follows (Only constant values are provided with bold letters)
First READ Operation
- operations[0]/nodeId/identifierType
- operations[0]/nodeId/namespaceIndex
- operations[0]/nodeId/identifier
- operations[0]/operationType READ
- operations[1]/nodeId/identifierTyp
- operations[1]/nodeId/namespaceIndex
- operations[1]/nodeId/identifier
- operations[1]/operationType READ
Note: The specific values are NOT defined here!
Output parameters
You can return all Output Parameter like this:
Parameter Name: /
Data Type: String
If you want to get only selected Output Parameter, use the following syntax:
Parameter Name: operationsResult/[0]/dataType/name (exemplary)
Data Type: depends on the Parameter you want to be returned.
For now, only the complete unformatted JSON will be returned.