WebID

Resources in PI Web API are addressed by WebIDs, which are persistent, URL-safe identifiers that encode the GUIDs and/or paths associated with objects in the PI System. WebIDs are often used in links, and can also be found inside JSON responses. Client applications can use WebIDs as opaque identifiers in other URLs or query parameters. Because WebIDs are persistent, clients can cache URLs containing WebIDs for future use, even in newer versions of PI Web API.

WebID version 2.0, introduced in PI Web API 2017 R2, provides different types of WebIDs, such as Full, IDOnly, PathOnly, LocalIDOnly, and DefaultIDOnly. The data type is string, and the default value is Full. Refer to PI Web API online help for full descriptions.

By specifying the WebID type, you can reduce WebID sizes (for URL length limitations), identify ambiguous paths and names of PI AF event frames and notifications, as well as accommodate path and name changes.

Note: WebIDs that were created by PI Web API 2017 and earlier and then persisted can be interpreted by PI Web API 2017 R2 and later.

Training video

To better understand how to use WebIDs, check out our video on YouTube:

https://www.youtube.com/embed/UbEfC_VqSBo