OPCTS - OPC UA Test Server

The opcts tool is a lightweight OPC UA server aimed to validate the IFW opcua client implementation and in general for integration tests. It reads a YAML file at startup and builds the address space (folders, variables, methods) accordingly. The server binary is ifwCoreOpcts and accepts the YAML path as its first argument (defaults to config.yaml):

ifwCoreOpcts -c protocol/open62541/test/resource/config/opcua_server.yaml

Command-line options

opcts supports a small CLI:

• -h / --help: Print usage.

• -c / --config <path>: YAML configuration file (default config.yaml).

• -e / --endpoint <uri>: Override the OPC UA endpoint URL. Default: opc.tcp://127.0.0.1:4846.

Configuration file

The YAML schema is split into four sections. Unknown keys are ignored, and most fields are mandatory unless marked optional.

server

• endpoint: OPC UA endpoint URL, e.g. opc.tcp://0.0.0.0:4840. The port is extracted from this string.

• namespaceUri: Namespace URI used for all nodes defined in the file.

folders (optional)

List of folders to create before adding nodes and methods. Each entry supports:

• name: Display/browse name.

• nodeId: String node id used when attaching children.

• parent: Optional parent folder id; defaults to Objects (the standard objects folder in namespace 0).

nodes

List of variable nodes. Supported datatypes are Double, Float, Int32, UInt32, Int16, UInt16, Boolean and String.

• name: Display/browse name.

• nodeId: String node id for the variable.

• datatype: One of the supported OPC UA scalar types.

• folder: Optional parent folder id; defaults to Objects.

• writable: Optional, default true. When false only read access is enabled.

• isArray: Optional flag; automatically set when initialValues is present.

• initialValue: Scalar initial value as a string/number.

• initialValues: Sequence of values for array nodes; array dimensions are inferred from the length.

Waveform simulation (scalar nodes only) is configured with simulation:

• type: sine or ramp.

• intervalMs: Update period in milliseconds (default 1000).

• For sine: periodMs (default 10000), amplitude (default 1.0), offset (default 0.0).

• For ramp: step (default 1.0), min (default 0.0), max (default 100.0).

methods (optional)

List of method nodes to expose under the namespace.

• name / nodeId / folder: Same meaning as variable nodes.

• inputArguments / outputArguments: Lists of argument objects with name, datatype (same set as variables) and optional description.

Simple server-side simulations can be enabled via simulation:

• type: fixed with outputs: list of values mapped to the declared output arguments.

• type: sumInt32: expects two Int32 inputs and returns their sum in the first output argument; remaining outputs are default-initialised.

Example

The integration tests ship an example configuration at protocol/open62541/test/resource/config/opcua_server.yaml showing folders, scalar and array nodes, sine/ramp simulations, and two methods (a fixed reply and an Int32 adder).

server:
  endpoint: "opc.tcp://0.0.0.0:4840"
  namespaceUri: "http://example.com/integration-test/"

  folders:
  - name: "TestScalars"
    nodeId: "TestScalars"
    parent: "Objects"
  - name: "TestArrays"
    nodeId: "TestArrays"
    parent: "Objects"

  nodes:
    - name: "TestInt32"
      nodeId: "TestInt32"
      datatype: "Int32"
      initialValue: 51
      writable: true
      folder: "TestScalars"

    - name: "TestDouble"
      nodeId: "TestDouble"
      datatype: "Double"
      initialValue: 23.5
      writable: true
      folder: "TestScalars"

    - name: "TestInts"
      nodeId: "TestInts"
      datatype: "Int32"
      isArray: true
      initialValues: [2, 3, 4]
      folder: "TestArrays"
      writable: true

    - name: "TempSine"
      nodeId: "TempSine"
      datatype: "Double"
      initialValue: 20.0
      writable: true
      folder: "TestScalars"
      simulation:
      type: "sine"
      intervalMs: 1000
      periodMs: 10000
      amplitude: 5.0
      offset: 20.0

    methods:
      - name: "ResetStatus"
        nodeId: "ResetStatus"
        folder: "TestFolder"
        inputArguments: []
        outputArguments:
      - name: "Success"
        datatype: "Boolean"
        description: "True if reset succeeded"
        simulation:
        type: "fixed"
        outputs:
       - "true"