import logging
import sys
fmt = logging.Formatter("%(asctime)s - %(name)s - %(ip)s - %(username)s - %(message)s")
h_console = logging.StreamHandler(sys.stdout)
h_console.setFormatter(fmt)
logger = logging.getLogger("myPro")
logger.setLevel(logging.DEBUG)
logger.addHandler(h_console)
extra_dict = {"ip": "113.208.78.29", "username": "Petter"}
logger.debug("User Login!", extra=extra_dict)
extra_dict = {"ip": "223.190.65.139", "username": "Jerry"}
logger.info("User Access!", extra=extra_dict)

class LoggerAdapter(object):
 """
 An adapter for loggers which makes it easier to specify contextual
 information in logging output.
 """
 def __init__(self, logger, extra):
  """
  Initialize the adapter with a logger and a dict-like object which
  provides contextual information. This constructor signature allows
  easy stacking of LoggerAdapters, if so desired.
  You can effectively pass keyword arguments as shown in the
  following example:
  adapter = LoggerAdapter(someLogger, dict(p1=v1, p2="v2"))
  """
  self.logger = logger
  self.extra = extra
 def process(self, msg, kwargs):
  """
  Process the logging message and keyword arguments passed in to
  a logging call to insert contextual information. You can either
  manipulate the message itself, the keyword args or both. Return
  the message and kwargs modified (or not) to suit your needs.
  Normally, you'll only need to override this one method in a
  LoggerAdapter subclass for your specific needs.
  """
  kwargs["extra"] = self.extra
  return msg, kwargs
 def debug(self, msg, *args, **kwargs):
  """
  Delegate a debug call to the underlying logger, after adding
  contextual information from this adapter instance.
  """
  msg, kwargs = self.process(msg, kwargs)
  self.logger.debug(msg, *args, **kwargs)

import logging
import sys
# 初始化一個(gè)要傳遞給LoggerAdapter構(gòu)造方法的logger實(shí)例
fmt = logging.Formatter("%(asctime)s - %(name)s - %(ip)s - %(username)s - %(message)s")
h_console = logging.StreamHandler(sys.stdout)
h_console.setFormatter(fmt)
init_logger = logging.getLogger("myPro")
init_logger.setLevel(logging.DEBUG)
init_logger.addHandler(h_console)
# 初始化一個(gè)要傳遞給LoggerAdapter構(gòu)造方法的上下文字典對(duì)象
extra_dict = {"ip": "IP", "username": "USERNAME"}
# 獲取一個(gè)LoggerAdapter類(lèi)的實(shí)例
logger = logging.LoggerAdapter(init_logger, extra_dict)
# 應(yīng)用中的日志記錄方法調(diào)用
logger.info("User Login!")
logger.info("User Login!", extra={"ip": "113.208.78.29", "username": "Petter"})
logger.extra = {"ip": "113.208.78.29", "username": "Petter"}
logger.info("User Login!")
logger.info("User Login!")

# 使用extra默認(rèn)值：{"ip": "IP", "username": "USERNAME"}
2017-05-14 17:23:15,148 - myPro - IP - USERNAME - User Login!
# info(msg, extra)方法中傳遞的extra方法沒(méi)有覆蓋默認(rèn)值
2017-05-14 17:23:15,148 - myPro - IP - USERNAME - User Login!
# extra默認(rèn)值被修改了
2017-05-14 17:23:15,148 - myPro - 113.208.78.29 - Petter - User Login!
2017-05-14 17:23:15,148 - myPro - 113.208.78.29 - Petter - User Login!

import logging
import sys
class MyLoggerAdapter(logging.LoggerAdapter):
 def process(self, msg, kwargs):
  if 'extra' not in kwargs:
   kwargs["extra"] = self.extra
  return msg, kwargs
if __name__ == '__main__':
 # 初始化一個(gè)要傳遞給LoggerAdapter構(gòu)造方法的logger實(shí)例
 fmt = logging.Formatter("%(asctime)s - %(name)s - %(ip)s - %(username)s - %(message)s")
 h_console = logging.StreamHandler(sys.stdout)
 h_console.setFormatter(fmt)
 init_logger = logging.getLogger("myPro")
 init_logger.setLevel(logging.DEBUG)
 init_logger.addHandler(h_console)
 # 初始化一個(gè)要傳遞給LoggerAdapter構(gòu)造方法的上下文字典對(duì)象
 extra_dict = {"ip": "IP", "username": "USERNAME"}
 # 獲取一個(gè)自定義LoggerAdapter類(lèi)的實(shí)例
 logger = MyLoggerAdapter(init_logger, extra_dict)
 # 應(yīng)用中的日志記錄方法調(diào)用
 logger.info("User Login!")
 logger.info("User Login!", extra={"ip": "113.208.78.29", "username": "Petter"})
 logger.info("User Login!")
 logger.info("User Login!")

# 使用extra默認(rèn)值：{"ip": "IP", "username": "USERNAME"}
2017-05-22 17:35:38,499 - myPro - IP - USERNAME - User Login!
# info(msg, extra)方法中傳遞的extra方法已覆蓋默認(rèn)值
2017-05-22 17:35:38,499 - myPro - 113.208.78.29 - Petter - User Login!
# extra默認(rèn)值保持不變
2017-05-22 17:35:38,499 - myPro - IP - USERNAME - User Login!
2017-05-22 17:35:38,499 - myPro - IP - USERNAME - User Login!

import logging
from random import choice
class ContextFilter(logging.Filter):
  ip = 'IP'
  username = 'USER'
  def filter(self, record):
   record.ip = self.ip
   record.username = self.username
   return True
if __name__ == '__main__':
 levels = (logging.DEBUG, logging.INFO, logging.WARNING, logging.ERROR, logging.CRITICAL)
 users = ['Tom', 'Jerry', 'Peter']
 ips = ['113.108.98.34', '219.238.78.91', '43.123.99.68']
 logging.basicConfig(level=logging.DEBUG,
      format='%(asctime)-15s %(name)-5s %(levelname)-8s %(ip)-15s %(username)-8s %(message)s')
 logger = logging.getLogger('myLogger')
 f = ContextFilter()
 logger.addFilter(f)
 logger.debug('A debug message')
 logger.info('An info message with %s', 'some parameters')
 for x in range(5):
  lvl = choice(levels)
  lvlname = logging.getLevelName(lvl)
  filter.ip = choice(ips)
  filter.username = choice(users)
  logger.log(lvl, 'A message at %s level with %d %s', lvlname, 2, 'parameters')