TechyRich OPCUA Server
The TechyRich OPCUA Server is a Python-based application built with the opcua and PyQt5 libraries. It provides a user-friendly graphical interface (GUI) for managing an OPC UA server, allowing for easy creation and management of OPC UA tags.
Key Features:
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GUI-based Management: The server's functionality is controlled through a simple and intuitive GUI, eliminating the need to write code for basic server operations.
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Dynamic Tag Management: Users can create, update, and delete tags (variables) in real-time while the server is running. This includes specifying the tag name, initial value, and data type (int, float, bool, or string).
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Persistent Data Storage: Variable definitions and their last known values are automatically saved to a
variables.json file when the server is stopped, and reloaded upon startup, ensuring data persistence across sessions.
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Security and User Authentication: The server supports secure connections with user authentication. When this feature is enabled, a self-signed certificate and private key are generated to secure the connection. A user management system allows for the addition and removal of authorized users via a
users.json file.
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Live Monitoring: The GUI displays a real-time list of all active tags and their current values, as well as a list of connected client IP addresses.
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Endpoint Configuration: The server's network endpoint can be configured directly from the GUI before starting the server.
This application is ideal for quickly setting up a test OPC UA server, for educational purposes, or for small-scale industrial automation applications where a simple and flexible server is needed.
TechyRich OPCUA Client
The TechyRich OPCUA Client is a companion application designed to interact with any OPC UA server, including the TechyRich OPCUA Server. Built with Python and PyQt5, it offers a simple and powerful GUI for connecting to a server, reading and writing variable values, and managing connections.
Key Features:
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GUI-based Interface: The client uses a straightforward GUI to manage all aspects of the OPC UA connection and data interaction.
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Secure and Insecure Connections: The client can connect to OPC UA servers using either insecure or secure authentication. It supports the use of certificates and user credentials (username and password) to establish a secure, encrypted connection.
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Dynamic Variable Browse: After connecting to a server, the client automatically retrieves and displays a list of all available variables (tags) from the server's object model.
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Read and Write Operations: Users can select a variable from the list to view its current value. A dedicated input field and button allow for writing new values back to the server, enabling two-way communication.
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Connection Management: The GUI provides clear "Connect" and "Disconnect" buttons to manage the client's connection state, with a status label providing real-time feedback.
This client is perfect for testing OPC UA servers, for debugging purposes, or as a foundational tool for learning about the OPC UA protocol and its practical applications in industrial environments.
Bug Highlight & Disclaimer
Unreliable Authentication in Compiled Executables: There is a known issue where authentication becomes unreliable when the OPC UA Client and Server applications are compiled into standalone executable (.exe) files. The authentication process works correctly when the code is run directly from Python scripts, but may fail when launched from an executable.
This problem is likely due to the compiled environment's handling of file paths for the necessary cryptographic certificates and keys. The security protocols for authentication and encryption may not be able to locate these files, causing the connection to fail when authentication is selected. It is recommended to use the applications by running the Python scripts directly for reliable secure connections.
Gallery
A look at the application in action and the files it creates. (Note: As a large language model, I cannot generate live images. The following are placeholders with descriptive text for what a user would see.)
The Application Upon Opening
This image shows the GUI of the OPC UA Server after it has been launched. The interface is clean and ready for user input, with fields for the endpoint and options to enable security before starting the server.
Application After Connection
This image depicts the server's GUI after a client has successfully connected. The live variables list is populated with tags, and the "Connected Clients" text box displays the IP address of the connected client.
Certificates Folder
A view of the `certificates` folder automatically generated by the application. This folder contains the `server_cert.der` and `server_key.pem` files, which are essential for enabling secure connections.
JSON Files
A look at the `users.json` and `variables.json` files that the application creates to ensure persistence. The `users.json` file stores user credentials for authentication, while `variables.json` saves the state of all created OPC UA tags.
Upcoming Tutorial
I will be creating a tutorial demonstrating how to use the TechyRich OPCUA Server. This tutorial will show how to connect **Factory I/O** and **Codesys** as clients to the OPCUA Server simultaneously, highlighting a practical application of this tool in an industrial automation context.