kender kender - 3 months ago 14
Python Question

How do you log server errors on django sites

So, when playing with the development I can just set

settings.DEBUG
to
True
and if an error occures I can see it nicely formatted, with good stack trace and request information.

But on kind of production site I'd rather use
DEBUG=False
and show visitors some standard error 500 page with information that I'm working on fixing this bug at this moment ;)

At the same time I'd like to have some way of logging all those information (stack trace and request info) to a file on my server - so I can just output it to my console and watch errors scroll, email the log to me every hour or something like this.

What logging solutions would you recomend for a django-site, that would meet those simple requirements? I have the application running as
fcgi
server and I'm using apache web server as frontend (although thinking of going to lighttpd).

Answer

Well, when DEBUG = False, Django will automatically mail a full traceback of any error to each person listed in the ADMINS setting, which gets you notifications pretty much for free. If you'd like more fine-grained control, you can write and add to your settings a middleware class which defines a method named process_exception(), which will have access to the exception that was raised:

http://docs.djangoproject.com/en/dev/topics/http/middleware/#process-exception

Your process_exception() method can then perform whatever type of logging you'd like: writing to console, writing to a file, etc., etc.

Edit: though it's a bit less useful, you can also listen for the got_request_exception signal, which will be sent whenever an exception is encountered during request processing:

http://docs.djangoproject.com/en/dev/ref/signals/#got-request-exception

This does not give you access to the exception object, however, so the middleware method is much easier to work with.