如何在Python日志格式字符串中添加自定义字段？

formatter = logging.Formatter('%(asctime)s : %(message)s')

import logging
formatter = logging.Formatter('%(asctime)s %(app_name)s : %(message)s')
syslog.setFormatter(formatter)
logger.addHandler(syslog)

logging.info('Log message', app_name='myapp')
logging.info('Log message', {'app_name', 'myapp'})
logging.info('Log message', 'myapp')

logging.info('Log message', extra={'app_name': 'myapp'})

>>> import logging
>>> logging.basicConfig(format="%(foo)s - %(message)s")
>>> logging.warning('test', extra={'foo': 'bar'})
bar - test

>>> logging.warning('test')
Traceback (most recent call last):
  File "/usr/lib/python2.7/logging/__init__.py", line 846, in emit
    msg = self.format(record)
  File "/usr/lib/python2.7/logging/__init__.py", line 723, in format
    return fmt.format(record)
  File "/usr/lib/python2.7/logging/__init__.py", line 467, in format
    s = self._fmt % record.__dict__
KeyError: 'foo'
Logged from file <stdin>, line 1

import logging
class CustomLogger(logging.Logger):
   def debug(self, msg, foo, *args, **kwargs):
       extra = {'foo': foo}
       if self.isEnabledFor(logging.DEBUG):
            self._log(logging.DEBUG, msg, args, extra=extra, **kwargs)
   *repeat for info, warning, etc*
logger = CustomLogger('CustomLogger', logging.DEBUG)
formatter = logging.Formatter('%(asctime)s [%(foo)s] %(message)s') 
handler = logging.StreamHandler()
handler.setFormatter(formatter) 
logger.addHandler(handler)
logger.debug('test', 'bar')

2019-03-02 20:06:51,998 [bar] test

def debug(self, msg, *args, **kwargs):
    Log 'msg % args' with severity 'DEBUG'.
    To pass exception information, use the keyword argument exc_info with
    a true value, e.g.
    logger.debug("Houston, we have a %s", "thorny problem", exc_info=1)
    if self.isEnabledFor(DEBUG):
        self._log(DEBUG, msg, args, **kwargs)

def __init__(self, code):
    self.code = code
def filter(self, record):
    record.app_code = self.code
    return True

def __init__(self, className):
    self.logger = logging.getLogger(className)
    self.logger.setLevel(logging.ERROR)
@staticmethod
def getLogger(className):
    return Logger(className)
def logMessage(self, level, code, msg):
    self.logger.addFilter(LogFilter(code))
    if level == 'WARN':        
        self.logger.warning(msg)
    elif level == 'ERROR':
        self.logger.error(msg)
    else:
        self.logger.info(msg)

if __name__=='__main__':
    logger.logMessage('ERROR','123','This is an error')

import logging
import os
LOG_FORMAT = '%(asctime)s %(name)s %(levelname)s %(funcName)s %(lineno)s ClaimID: %(claim_id)s: %(message)s'
class AppLogger(logging.Logger):
    # Override all levels similarly - only info overriden here
    def info(self, msg, *args, **kwargs):
        return super(AppLogger, self).info(msg, extra={"claim_id": os.getenv("claim_id", "")})
def get_logger(name):
    """ This function sets log level and log format and then returns the instance of logger"""
    logging.setLoggerClass(AppLogger)
    logging.basicConfig(level=logging.INFO, format=LOG_FORMAT)
    logger = logging.getLogger(name)
    logger.setLevel(logging.INFO)
    return logger
LOGGER = get_logger(__name__)

如何在Python日志格式字符串中添加自定义字段？

5 个回答