Question

I’m trying to implement websockets using Tornado webserver.

My setup looks as follows:

from tornado.options import options, define, parse_command_line
import django.core.handlers.wsgi
import logging
import tornado.httpserver
import tornado.ioloop
import tornado.web
import tornado.wsgi

from pogows.tornado_sockets import GetSocketHandler, UpdateSocketHandler
from mobile.cleaner import start_cleaning

define('port', type=int, default=8080)
tornado.options.options['log_file_prefix'].set('/var/www/pogo_django/logs/tornado_server.log')
tornado.options.parse_command_line()

<snip>

def main():

    logger = logging.getLogger(__name__)
    wsgi_app = tornado.wsgi.WSGIContainer(
        django.core.handlers.wsgi.WSGIHandler())
    tornado_app = tornado.web.Application(
        [
            ('/hello-tornado', HelloHandler),
            ('/socket/get', GetSocketHandler),
            ('/socket/update', UpdateSocketHandler),
            ('.*', tornado.web.FallbackHandler, dict(fallback=wsgi_app)),
        ], debug=True)
    logger.info("Tornado POGO server starting...")
    server = tornado.httpserver.HTTPServer(tornado_app)
    server.listen(options.port)
    start_cleaning()
    tornado.ioloop.IOLoop.instance().start()

So far everything looks fine, tornado logs, I see the info message.
Now, I’m trying to log some stuff from websocket handler classes.

class GetSocketHandler(tornado.websocket.WebSocketHandler):

    def open(self):
        print "opening"

    def on_closed(self):
        print "closing"

    def on_message(self, message):
        last_update=datetime.datetime.utcnow().replace(tzinfo=utc)
        try:
            print "getting_user"
    ...

Tornado is governed by supervisord, with the following configuration:

[program:pogo_tornado] command=/var/www/pogo_django/tornado_server.py
user=www-data stdout_logfile=/var/www/pogo_django/logs/pogo_stdout.log
stderr_logfile=/var/www/pogo_django/logs/pogo_stderr.log
environment=PYTHONPATH=”/var/www/pogo_django/”,DJANGO_SETTINGS_MODULE=”pogo.settings”

I tried a few things.

1. Just use print statements, as you see from the above snippet, hoping for supervisord to catch it and send to stdout/stderr logs.
2. Create a separate logging.getLogger() instance inside the websocket class and use that.

None of it produces desired results.

When I run tornado from commandline by hand, I do see the print version printed to console, but logging doesn’t work anyway.

Where do I go wrong?

Answer 1

Bah, I got it. I was using getLogger() without setting logging level and just blindly logging to DEBUG.

Explicitly using logger.setLevel(logging.DEBUG) showed me my messages in the logs.

Apparently Tornado sets some other level by defaults.. Stupid me.