python使用装饰器作日志处理

   装饰器这东西我看了一会儿才明白，在函数外面套了一层函数，感觉和java里的aop功能很像；写了2个装饰器日志的例子，
第一个是不带参数的装饰器用法示例，功能相当于给函数包了层异常处理，第二个是带参数的装饰器用法示例，将日志输出到文
件。 


```
#coding=utf8
import traceback
import logging
from logging.handlers import TimedRotatingFileHandler
def logger(func):
	def inner(*args, **kwargs): #1
		try:
			#print "Arguments were: %s, %s" % (args, kwargs)
			func(*args, **kwargs) #2
		except:
			#print 'error',traceback.format_exc()
			print 'error'
	return inner


def loggerInFile(filename):#带参数的装饰器需要2层装饰器实现,第一层传参数，第二层传函数，每层函数在上一层返回
	def decorator(func):
		def inner(*args, **kwargs): #1
			logFilePath = filename  # 日志按日期滚动，保留5天
			logger = logging.getLogger()
			logger.setLevel(logging.INFO)
			handler = TimedRotatingFileHandler(logFilePath,
											   when="d",
											   interval=1,
											   backupCount=5)
			formatter = logging.Formatter('%(asctime)s  - %(levelname)s - %(message)s')
			handler.setFormatter(formatter)
			logger.addHandler(handler)
			try:
				#print "Arguments were: %s, %s" % (args, kwargs)
				result = func(*args, **kwargs) #2
				logger.info(result)
			except:
				logger.error(traceback.format_exc())
		return inner
	return decorator

@logger
def test():
	print 2/0

test()


@loggerInFile('newloglog')
def test2(n):
	print 100/n

test2(10)
test2(0)
print 'end'


```