How to configure/initialize logging using logger for multiple modules only once in Python for entire project?

2
votes

I have python project with multiple modules with logging. I perform initialization (reading log configuration file and creating root logger and enable/disable logging) in every module before start of logging the messages. Is it possible to perform this initialization only once in one place (like in one class may be called as Log) such that the same settings are reused by logging all over the project?

I am looking for a proper solution to have only once to read the configuration file and to only once get and configure a logger, in a class constructor, or perhaps in the initializer (__init__.py). I don't want to do this at client side (in __main__ ). I want to do this configuration only once in separate class and call this class in other modules when logging is required.

4
python

4 Answers

2
votes

setup using @singleton pattern

#log.py
import logging.config 
import yaml
from singleton_decorator import singleton

@singleton
class Log:

    def __init__(self):

        configFile = 'path_to_my_lof_config_file'/logging.yaml

        with open(configFile) as f:
            config_dict = yaml.load(f)     
        logging.config.dictConfig(config_dict)
        self.logger = logging.getLogger('root') 

    def info(self, message):
        self.logger.info(message)

#module1.py 
from Log import Log     

 myLog = Log()
 myLog.info('Message logged successfully)



   #module2.py 
    from Log import Log     

     myLog = Log() #config read only once and only one object is created
     myLog.info('Message logged successfully)
0
votes

You can initialize and configure logging in your main entry point. See Logging from multiple modules in this Howto (Python 2.7).

0
votes

I had the same problem and I don't have any classes or anything, so I solved it with just using global variable

utils.py:

existing_loggers = {}


def get_logger(name='my_logger', level=logging.INFO):
    if name in existing_loggers:
        return existing_loggers[name]

    # Do the rest of initialization, handlers, formatters etc...
0
votes

From the documentation,

Note that Loggers should NEVER be instantiated directly, but always through the module-level function logging.getLogger(name). Multiple calls to getLogger() with the same name will always return a reference to the same Logger object.