Using ValueProvider<Long> with FixedWindows and Duration #18704
Description
Moving toward Apache Beam 2.x, I want to use templates as much as possible, and ValueProvider accordingly.
In my logic, I am using a FixedWindow, but the duration is flexible, so I rather get it from a ValueProvider.
The problem is that FixedWindows.of() only get Duration, and I failed to find a simple way to grab a ValueProvider and make a duration out of it.
According to Eugene Kirpichov "Unfortunately this question has a simple answer: this is currently not supported"
Imported from Jira BEAM-3378. Original Jira may contain additional context.
Reported by: shushu.