importlib应用 - django

背景

仿django的中间件的编程思想

用户可通过配置，选择是否启用某个组件/某个功能，只需要配置

eg:报警系统，发邮件，发微信 。。。

( 根据字符串导入模块， 利用反射找到模块下的类，实例化。执行 )

code

# settings.py

NOTIFY_LIST = [

    'notify.email.Email',

    'notify.msg.Msg',

    'notify.wechat.Wechat',

]

-----------------------------

# app.py

from notify import send_xxx

def run():

    send_xxx("报警")

if __name__ == "__main__":

    run()

----------------------------

# notify/__init__.py

# 根据字符串 导入模块

import settings

import importlib

def send_xxx(content):

    for path in settings.NOTIFY_LIST:

        # 'notify.email.Email',

        # 'notify.msg.Msg',

        # 'notify.wechat.Wechat',

        module_path,class_name = path.rsplit('.',maxsplit=1)

        # 根据字符串导入模块

        module = importlib.import_module(module_path)

        # 根据类名称去模块中获取类

        cls = getattr(module,class_name)

        # 根据类实例化

        obj = cls()

        obj.send(content)

-----------------------------

# notify/email.py

class Email(object):

    def __init__(self):

        pass

    def send(self,content):

        print("email send..")

# notify/msg.py

class Msg(object):

    def __init__(self):

        pass

    def send(self,content):

        print("msg send..")



# notify/wechat.py

class Wechat(object):

    def __init__(self):

        pass

    def send(self,content):

        print("wechat send..")