Whitelabel Error Page
This application has no configured error view, so you are seeing this as a fallback.
Tue Sep 03 17:20:45 PDT 2019
There was an unexpected error (type=Internal Server Error, status=500).
block()/blockFirst()/blockLast() are blocking, which is not supported in thread reactor-http-nio-4
It seems that here, standard subscription mechanism should be used instead of manually calling .block