No1 观察者模式
定义了对象之间的一对多依赖。当被观察者对象改变状态时，它的所有依赖者（观察者）都会收到通知并更新状态。
#可以继承一个抽象类
class Observer():
"""观察者基类"""
# @abstractmethod
def update(self, observable, object):
pass
class Observable:
"""被观察者的基类"""
def __init__(self):
self.__observers = []
def addObserver(self, observer):
self.__observers.append(observer)
def removeObserver(self, observer):
self.__observers.remove(observer)
def notifyObservers(self, object):
for obj in self.__observers:
obj.update(self, object)
'''
举例:异地登录提醒
'''
import time
class Account(Observable):
def __init__(self):
super().__init__()
self.__lastIp = {}
self.__lastRegion = {}
def __getRegion(self, ip):
#由IP地址获取地区信息。这里只是模拟，真实项目中应该调用IP地址解析服务。
ipRegions = {
"101.47.18.9":"浙江杭州",
"67.218.147.69":"美国洛杉矶",
}
# region = ipRegions[ip]
region = ipRegions.get(ip)
return "" if region is None else region
def __isLongDistance(self, name, region):
# 计算本次登录与最近几次登录的距离
# 真实项目中调用地理信息相关服务
lastRegion = self.__lastRegion.get(name)
return lastRegion is not None and lastRegion != region
def login(self, name, ip, time):
region = self.__getRegion(ip)
if self.__isLongDistance(name, region):
self.notifyObservers({"name":name,"ip":ip,"region":region,"time":time})
self.__lastRegion[name] = region
self.__lastIp[name] = ip
class SmsSender(Observer):
def update(self, observable, object):
print("[短信发送] " + object["name"] + "您好！检测到您的账户可能登录异常。最近一次登录信息：\n"
+ "登录地区：" + object["region"] + " 登录ip：" + object["ip"] + " 登录时间："
+ time.strftime("%Y-%m-%d %H:%M:%S", time.gmtime(object["time"])))
class MailSender(Observer):
"""邮件发送器"""
def update(self, observable, object):
print("[邮件发送] " + object["name"] + "您好！检测到您的账户可能登录异常。最近一次登录信息：\n"
+ "登录地区：" + object["region"] + " 登录ip：" + object["ip"] + " 登录时间："
+ time.strftime("%Y-%m-%d %H:%M:%S", time.gmtime(object["time"])))
if "__main__" == __name__:
accout = Account()
accout.addObserver(SmsSender())
accout.addObserver(MailSender())
accout.login("Tony", "101.47.18.9", time.time())
accout.login("Tony", "67.218.147.69", time.time())