This is using web.py with uwsgi.
When I return page data from a POST handler, the browser receives a blank page instead. GET handlers are working fine for me. The handler is being called correctly, and redirects (web.seeother) will work.
To answer my own question, you need to call web.input() otherwise the returned data will be ignore (who knows why? is it a bug?)
Page returned by POST handler ignored - get blank response (web.py)