Handling External Changes in AFAttributes for PI Systems

Handling External Changes in AFAttributes for PI Systems

Working with OSIsoft's PI System, particularly with AF (Asset Framework), ensures robust data management and asset maintenance. However, scenarios arise when handling external configurations such as changes in AFAttributes, especially when AFAttributes point to different PIPoints while using an AFDataPipe. This post will guide you through managing such changes without needing to restart your processes.

Understanding the Problem

Imagine you have an AFDataPipe initialized to monitor changes in AFAttributes. You are subscribing to updates and handling events as and when they occur. But then, a configuration change is made externally — an AFAttribute that used to point to a specific PIPoint is now reconfigured to point to a different one. As a result, your current AFDataPipe signups no longer receive updates, and typically, the straightforward workaround might be to restart your system. Fortunately, there is a way to handle this more gracefully.

Solution: Update and Adapt

To manage such external changes efficiently, follow these steps:

1. Detect Configuration Changes: Use PISystem.FindChangedItems to track any configuration changes made to AFAttributes. This method retrieves the changes from the PI Server and signals necessary updates.

2. Refresh AFAttributes: After identifying the changes, invoke AFChangeInfo.Refresh(). This operation updates the loaded AFAttribute objects, ensuring they align with the recent configuration adjustments from the PI Server.

3. Apply Changes to AFDataPipe: Finally, call AFDataPipe.ProcessAppliedChanges(). This crucial step synchronizes your AFDataPipe signups with the changes, reflecting updates to the newly pointed PIPoints without requiring a restart or the hassle of re-signing.

Benefits of This Approach

By following this method, your applications will remain robust and responsive to changes. This not only minimizes downtimes but also enhances system reliability and user trust — ensuring that your data integrity and processes are never compromised by configuration changes.

In Conclusion

Managing configuration changes in an AF environment need not be fraught with disruptions. With API functionalities such as FindChangedItems, Refresh, and ProcessAppliedChanges, you can efficiently handle external alterations, keeping your data pipelines continuous and consistent. Embrace these tools to ensure your systems are both adaptable and resilient in the face of changes.

By understanding and implementing these techniques, you are ensuring your PI System remains dynamic and responsive to real-world operational changes, all while maintaining high performance and reliability.