[PYTHON] Output user information etc. to Django log

If you try to output information that is not in the LogRecord attribute such as request user information to the Django log,

logger.info(message, extra={'username' : request.user.username})

You can find something like this, but it's a little different. There was a solution when I thought that there were development members who did not follow the rules and that it only worked for the logs I wrote.

Overview

-Use Middleware to set user information to threading.local () when requesting -Add user information of threading.local () to LogRecord with logging.filter --LOGGING settings in settings.py

Middleware --Get username from request. (If it's an API, you can pharse JWT to get user information ...) --Set the username obtained above to threading.local (). (For reference from the filter below) --Set None to clear after self.get_response (request)

python

import logging
import threading

local = threading.local()

class CustomAttrMiddleware:
    """
Middleware to get the custom item to output to log
    """
    def __init__(self, get_response):
        self.get_response = get_response

    def __call__(self, request):
        """
Get the username of the request when requesting from the client
        threading.local()Temporarily save to
        """
        if request.user:
            setattr(local, 'user', request.user.username)
        else:
            setattr(local, 'user', None)

        response = self.get_response(request)

        #Clear when responding
        setattr(local, 'user', None)

        return response

filter --Set the username set in threading.local () in Middleware to LogRecord. --Be sure to return True.

python

class CustomAttrFilter(logging.Filter):
    """
filter for outputting custom items to log
    """
    def filter(self, record):
        record.user = getattr(local, 'user', None)
        return True

settings.py --Add the Middleware created above. --Added user output format (user =% (user) s) to LOGGING formatters --Add the filter created above to the filters of LOGGING --Set the added filter to be used by LOGGING handlers

python

MIDDLEWARE = [
     ...
    'middleware.custom_logging.CustomAttrMiddleware',
]

LOGGING = {
     ...
    'formatters': {
        'verbose': {
            'format': '%(levelname)s %(asctime)s %(module)s '
                      '%(process)d %(thread)d user=%(user)s %(message)s'
        },
    },
    'filters' : {
        'custom': {
            '()': 'middleware.custom_logging.CustomAttrFilter'
        },
    },
    'handlers': {
        'console': {
            'level': 'DEBUG',
            'class': 'logging.StreamHandler',
            'formatter': 'verbose',
            'filters': ['custom']
        },
    },
     ...
}

views (for operation check)

python

class LoggingExceptListView(generics.ListAPIView):
    """
ListView to see exception output in the log
    """
    def list(self, request, *args, **kwargs):
        """
Just raise an Exception
        """
        raise Exception('For checking logs')

log output result

--Execute the above operation check views --The "user = CustomAttrUser" part of the log below

python

ERROR 2020-05-06 17:12:02,703 log 13516 10376 user=CustomAttrUser Internal Server Error: /sample_api/logging-exp/
Traceback (most recent call last):
  File "C:\ProgramData　...
　...  raise Exception('For checking logs')

Source

https://github.com/ping2shi2/DRF-sample

References

• Django: Adding a Custom Attribute to All Log Lines