Create Profiling JobManager/TaskManager Instance failed

I'm test the "async-profiler" feature in version 1.19, but when I submit a task in yarn per-job mode, I get an error  when I click Create Profiling Instance on the flink Web UI page.

The error message obviously means that the yarn proxy server does not support POST calls. I checked the code of WebAppProxyServlet.java and found that the POST method is indeed not supported, so I changed it to PUT method and the call was successful.