上下文和装饰器优雅，灵活地处理异常

如何优雅地处理异常

• 尽量精确捕获异常
• 如果是接口或函数方式，尽量高度抽象，不要影响了代码的可读性和灵活性

上下文方式

# 上下文处理异常
class RaiseCode:
    REQUEST_TIMEOUT = "请求超时"
    zero_divisor = ZeroDivisionError({"retcode": 1, "stderr": "被除数不能为零"})


class RaiseContent:

    def __init__(self, captures, code_name):
        self.captures = captures
        self.code = getattr(RaiseCode, code_name)

    def __enter__(self):
        self

    def __exit__(self, exc_type, exc_val, exc_tb):
        if exc_type == self.captures:
            raise self.code


def test_raise_1():
    result = 1 / 0
    return result


def test_raise_2():
    with RaiseContent(ZeroDivisionError, "zero_divisor"):
        result = 1 / 0
        return result


def main():
    try:
        print(test_raise_2())
    except Exception as e:
        print(e)


if __name__ == "__main__":
    main()

测试

image.png

装饰器方式

from functools import wraps

def decorate_raise(func):
    @wraps(func)
    def wrap(*args, **kwargs):
        try:
            return func(*args, **kwargs)
        except Exception as e:
            return e
    return wrap


@decorate_raise
def test_raise_3():
    if 0 != 1:
        raise Exception({"retcode": 1, "stderr": "为了测试特意抛出的异常"})


def main_decorate():
    print(test_raise_3())

测试

image.png

参考：
https://github.com/piglei/one-python-craftsman/blob/master/zh_CN/6-three-rituals-of-exceptions-handling.md