I am using spring-boot 2.1.7.RELEASE, and packaged it as war deployed in a Tomcat 8.5.45.
I have a async rest controller, when it take long time to process and throw a AsyncRequestTimeoutException, The client get a response with status == 200 and empty body.
When packaged as jar and run with embedded tomcat, I can get 503 error.
I debugged in and found ErrorPageFilter suppressed the status, and doesn't send any body to client.