如何在Django代码中进行logging.DEBUG？

Question

In django we have settings.py that defines the DEBUG for the whole project.

Now, My have debug level is independently configured in settings.py.

How should I use logging.DEBUG ?

Way1:

if settings.DEBUG:
    logging.debug("Debug message")

Way2:

# Without checking settings.DEBUG
logging.debug("Debug message")

What is a good practice ?

I think we should use Way2 since logging level already decides - if the message will be logged or not. But, some say that Way1 is a standard practice.

Answer 1

I think it's not a good thing to rely too much on a global setting such as DEBUG, which changes the whole behavior of your app.

What if you want to audit code and log stuff in production ? You're not going to turn DEBUG to true to do this, are you ? You'd rather tone down your log filter.

On a more stylistic point of view, it makes little sense and is not very pythonistic to have 2 settings (DEBUG and log level) affect a single behavior.

Long answer short: my opinion is that method 2 is superior, technically and stylisticly speaking.

Answer 2

The second method is fine, and in fact i use it all the time.

The only reason I am putting an answer here is because we in-fact did something like (1) in a work project a few years back, it turned out that although we were not logging anything at debug level in production to a file the cost of creating the debug message was in itself quite expensive and impacting performance.

ie

• (1) In production the debug level message is not created at all, just a boolean check instead.
• (2) In production the debug messages are created and propagated but just not logged into a file (well if that is in fact how you have setup your logging).

The project was a pretty big calculation farm where every ounce of performance mattered, this hasn't been the case for me ever since and might not be the case for you, but hey... i just thought i would mention it.