UaoForQuasar - UA Objects for quasar-based OPC UA Servers

UaoForQuasar (UA Objects) is a code generation tool that creates type-safe OPC UA client classes in C++ based on quasar server designs. It simplifies OPC UA client development by generating client code that matches your quasar server's information model.

Overview

UA Objects uses a priori information from your OPC UA server's information schema to generate client classes that are specifically tailored to your application. This approach provides several benefits:

Advantages

• No OPC UA expertise required - Create type-safe OPC UA clients without deep protocol knowledge
• Type safety - Generated code ensures type correctness at compile time
• Error handling - Built-in error handling for OPC UA operations
• Clean abstraction - Use your OPC UA server's objects directly in client code

Limitations

• Client classes are specific to your quasar application design
• Currently handles only single requests to OPC UA Read Service (not batch operations)
• Requires Unified Automation SDK (UASDK)

Requirements

• quasar Framework - UaoForQuasar must be deployed in a quasar project
  • Reference: https://github.com/quasar-team/quasar
• Unified Automation SDK - The generated client code depends on UASDK
  • Commercial: https://www.unified-automation.com/products/server-sdk/c-ua-server-sdk.html
  • Evaluation license available for testing
• Python Dependencies
  • Jinja2 (templating engine)
  • colorama (terminal coloring)
  • pyuaf (OPC UA Access Framework)

Quick Start

1. Add UaoForQuasar to your quasar project

# In your quasar project directory
git submodule add https://github.com/quasar-team/UaoForQuasar.git
git submodule update

2. Generate client classes

Generate a client class for each quasar class you want to access:

python UaoForQuasar/generateClass.py MyClass

You can specify a C++ namespace for your generated code:

python UaoForQuasar/generateClass.py --namespace MyProject MyClass

Generated files will be placed in UaoForQuasar/generated/.

3. Use the generated client

The following example shows how to use a generated client class:

#include <ClientSessionFactory.h>

// Include your generated client class
#include <MyClass.h>

#include <uaplatformlayer.h>
#include <iostream>

int main()
{
    UaPlatformLayer::init();

    UaClientSdk::UaSession* session = ClientSessionFactory::connect("opc.tcp://127.0.0.1:4841");
    if (!session)
        return -1;

    MyClass myObject(session, UaNodeId("instance1", 2));
    
    std::cout << "Value = " << myObject.readMyVariable() << std::endl;
    
    return 0;
}

Demo Application

A demo application is included to show how to use the generated client code:

1. Navigate to the demo directory
2. Adjust demo.cpp to use your generated class
3. Modify CMakeLists.txt to set the correct paths for UASDK
4. Build the demo:

cd UaoForQuasar/demo/build
cmake ../
make

Contact

For questions or issues, contact: paris.moschovakos@cern.ch