While accessing public WEB API endpoint https://devdata.osisoft.com/piwebapi Element value is getting returned only once.
Observed issue with https://devdata.osisoft.com/piwebapi/streamsets/<WebID>/value API, observed same issue with VLE created server also.
Another que with same issue has following comment :
Due to performance considerations, you cannot use the Cache-Control header on bulk data operations by default. However, you can change this setting by adding/setting a Runtime configuration IgnoreCacheControlForBulkRequests item and setting Value Type to Boolean and Value to true. See Configuration at runtime .
But nowhere it is mentioned how to configure this.
Following are the screenshots of the issue i.e. when trying to issue GET call for value multiple times
First time Response
Retry of same API call
Observed that GET call for element value is working only once, after that it is giving Error response.