Global variables lost in Bottle route

Question

I'm using Bottle as Python web framework.

Basically, here is what I am doing :

auth.py :

from bottle import get

logger = None
webserver = None

def load(server):
    global logger, webserver

    logger = server.getLogger('auth')
    webserver = server

@get('/auth')
def auth():
    logger.debug('Entering route')

webserver.py :

import bottle
import imp

class WebServer(object):
    # ...

    def getLogger(self, name):
        # ...

    def start_wsgi(self):
        # ...

        app = bottle.default_app()

        mod = imp.load_source('auth', 'auth.py')
        mod.load(self)

        # ...

        return app

    # ...

ws = WebServer()
app = ws.start_wsgi()

NB: no error handling or extra code here, I just exposed what is interesting to the issue (in my opinion)

It seems that the global scope is not shared between the main process (which runs the WebServer code) and the thread handling the request (logger is still None when I hit the /auth URL).

By printing id(logger) in function load() and route auth() (with a global logger added, just to be sure), I get two different ids.

How can I share my loggers to the threads handling the request ?

PS: I tried adding a field to the default Bottle application, like this :

app = default_app()
app.logger = # mylogger

And then in the route :

app = default_app()
app.logger.debug('Message')

But it seems that even the default_app() is different.

score 1 · Answer 1 · edited May 23 '17 at 12:27

1

How can I share my loggers to the threads handling the request ?

...

By printing id(logger) in function load() and route auth() (with a global logger added, just to be sure), I get two different ids.

That's okay--your logger variables need not reference the same logger object for things to work properly across threads.

Each thread should just acquire its logger:

logger = logging.getLogger('foo.bar.baz')

That will work just fine. (Across threads, mind you, not across processes.)

Btw, I'm not sure what your Webserver.getLogger function returns, but in any case this function seems unnecessary.

P.S., Just curious--Are you actually seeing a problem with your logging output, or were you just surprised when you observed that the ids of the different logger variables were not identical?

edited May 23 '17 at 12:27

Community

1
1

answered Jun 10 '14 at 18:35

ron rothman

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The function ``Webserver.getLogger`` initialize the logger to the same logging level used in the ``Webserver`` class. And I still need the global reference to ``webserver`` (same issue as ``logger``) – linkdd Jun 10 '14 at 20:23
Then I'm afraid I'm not clear exactly what you're asking. What's stopping you from referencing `webserver`? – ron rothman Jun 10 '14 at 21:02
That's the point of the question, in the route ``/auth``, ``webserver`` and ``logger`` are ``None`` even if the ``load()`` function was called by the webserver. – linkdd Jun 11 '14 at 07:37
ANy solutions to this? – felipeclopes Jun 11 '14 at 20:34
Need to see what `getLogger` returns. Can't run this code (to reproduce) otherwise. – ron rothman Jun 11 '14 at 20:57
``getLogger`` is not the problem since both ``logger`` and ``webserver`` are ``None`` in ``/auth``. But it just perform a ``logging.getLogger`` followed by a ``logger.setLevel(self.loglevel)`` – linkdd Jun 12 '14 at 15:12

Global variables lost in Bottle route

1 Answers1