用Python装饰器给函数自动加上try except

用装饰器实现把函数用try...except包起来：

import logging
import traceback
from functools import wraps

logging.basicConfig(filename='error.log',
                    level=logging.INFO,
                    format='%(levelname)s::%(name)s::%(asctime)s::%(filename)s,line %(lineno)s, in %(funcName)s(),msg:%(message)s'
                    )
#定义装饰器error_handler
def error_handler(func):
    @wraps(func) #关键行
    def wrapper(*args, **kwargs):
        try:
            return func(*args, **kwargs)
        except:
            msg=traceback.format_exc()
            logging.error(msg)
            return 'error'
    return wrapper #返回函数名

#用法示例：自动处理test()的异常
@error_handler
def test():
    a=1/0
    return a

if __name__=='__main__':
    test()

 不需要wraps的写法：

def timeit(func):
    def wrapper(*args,**kwargs):
        start=time.time()
        print('{}:{}() started.'.format(get_now_str(),func.__name__))
        res=func(*args,**kwargs)
        end=time.time()
        print('{}:{}() ended.'.format(get_now_str(),func.__name__))
        print('time elapsed:{:.4f} seconds.'.format(end-start))
        return res
    return wrapper