Easy application logging/debugging with nginx, uwsgi, flask?

Question

I\'m not looking to turn on the dangerous debugging console, but my application is getting a 500 error and doesn\'t seem to be writing any output for me to investigate more deep

Answer 1

Set config['PROPAGATE_EXCEPTIONS'] to True when running app in production and you want tracebacks to be logged into log files. (I haven't tried with SMTP handler, though..)

Answer 2

I know that this is a VERY old post, but I ran into the issue now, and it took me a bit to find the solution. Flask sends errors to the server. I was running Gunicorn with an upstart script on Ubuntu 14.04 LTS, and the place where I found the error logs was as follows:

/var/log/upstart/myapp.log

http://docs.gunicorn.org/en/stable/deploy.html#upstart

Just in case some other poor soul ends up in this situation.

Answer 3

1. The part where you create handlers, add to loggers etc. should be in the if __name__ == '__main__' clause, i.e. your main entry point. I assume that would be run.py.
2. I'm not sure I can answer this - it depends on what you want. I'd advise looking at the logging tutorial to see the various options available.
3. I don't believe you need to change anything at the nginx level.

Update: You might want to have an exception clause that covers uncaught exceptions, e.g.

if __name__ == '__main__':
    try:
        app.run(debug=True)
    except Exception:
        app.logger.exception('Failed')

which should write the traceback of any exception which occurred in app.run() to the log.