Django logging to console

I am writing this for easy understanding dummies like me.

In settings.py

LOGGING = {
    'version': 1,
    'disable_existing_loggers': False,
    'handlers': {
        'console': {
            'class': 'logging.StreamHandler',
        },
    },
    'loggers': {
        'app_api': {
            'handlers': ['console'],
            'level': 'INFO',
        },
    },
    }

Somewhere in your application views

import logging
logger = logging.getLogger('app_api') #from LOGGING.loggers in settings.py

try:
    one = 1/0
except Exception as e:
    logger.error(e)

The following script:

import logging, logging.config
import sys

LOGGING = {
    'version': 1,
    'handlers': {
        'console': {
            'class': 'logging.StreamHandler',
            'stream': sys.stdout,
        }
    },
    'root': {
        'handlers': ['console'],
        'level': 'INFO'
    }
}

logging.config.dictConfig(LOGGING)
logging.info('Hello')

writes Hello to sys.stdout, as can be verified by piping its output to a file. So your problem is likely to be somewhere else (or possibly that sys.stdout isn't what you expect). You could try with sys.__stdout__ to see if that makes a difference.


I finally got it. Here's what was happening.

When you define a logger using getLogger, you give a logger a name, in this case

logger = logging.getLogger(__name__)

and you then have to define how a logger with that name behaves in the LOGGING configuration. In this case, since that file is inside a module, the logger's name becomes myApp.page_processors, not page_processors, so the logger named 'page_processors' in the LOGGING dict is never called. So why was the logging to the file working? Because in the (...) that I show in the code there is another logger named 'myApp' that apparently gets called instead, and that one writes to the file.

So the solution to this question is just to properly name the logger:

LOGGING = {
    # (...)
    'loggers': {
        # (...)
        'myApp.page_processors': {
            'handlers': ['console','file'],
            'level': 'DEBUG',
        }
    }
    # (...)
}