Ok, here\'s the code where I setup everything:
if __name__ == \'__main__\':
app.debug = False
applogger = app.logger
file_handler = FileHandler
Ok, my failure stemmed from two misconceptions:
1) Flask will apparently ignore all your custom logging unless it is running in production mode
2) debug=False is not enough to let it run in production mode. You have to wrap the app in any sort of WSGI server to do so
After i started the app from gevent's WSGI server (and moving logging initialization to a more appropriate place) everything seems to work fine