uwsgi + nginx + flask: upstream prematurely closed

Question

I created an endpoint on my flask which generates a spreadsheet from a database query (remote db) and then sends it as a download in the browser. Flask doesn\'t throw any er

Answer 1

In my case, problem was nginx was sending a request with uwsgi protocol while uwsgi was listening on that port for http packets. So either I had to change the way nginx connects to uwsgi or change the uwsgi to listen using uwsgi protocol.