Java: Anyone using Websockets or other reactive programming in Java

[glparker]

We are dabbling with using Websockets to enable 2-way communication between one of our webapplications and the teachers browser.   Ideally we'll use the KState Java library callback  function to send data along the WebSocket pipe to the browser.   But, there's a lot of tech in this stack and we're stuck figuring out what we don't know.

Does anyone have an example of a Java server application using the KState callback features to provide a more reactive customer experience, using Websokcets or something else?   

[matthew_buckett]

We're in the process of writing an application and are using Server Sent Events (SSE) to push updates back to the client in real time. They aren't supported by IE 11 and old Edge versions, but Canvas is dropping support for  IE 11 and Edge will become less of a problem over time (and you can always polyfill it).

Server-side it's a Spring Boot application which uses LTI 1.3 through our LTI 1.3 library, along with this Spring SSE Library. We have a static React/Redux frontend build using Instructure UI.