WebUI: Investigate and fix issue of streaming endpoints not terminating properly

Currently we are using HTTP standard AbortController to terminate gRPC streaming endpoints. It doesn’t seem like it is working. It is noticeable when viewing hp visualizations. When clicking around the various graphs in hp-viz, multiple streaming endpoints are called, but after about 4th click, the page will show a spinner. If we look at the Network tab on the browser, we’ll observe that the latest streaming endpoint call ends up in a Pending state because there were about 8~12 gRPC streaming endpoints that are still open and have not terminated yet.

[hkang1]

https://github.com/hamidzr/determined/tree/stream-abort

I see, thanks, this was REALLY helpful. Looking again at the hp-viz section, it’s possible the cleanup portion in the useEffects are not calling the cleanup callback properly. I’ll take a look.

[hamidzr]

a separate issue but we can probably get these two streaming request to be closed by the server in terminal states

curl 'http://xyz/api/v1/trials/2692/logs/fields?follow=true' \
  --compressed \
  --insecure

curl 'http://MYSERVER/api/v1/experiments/1828/hyperparameter-importance' \
  --compressed \
  --insecure