Python design pattern-Observer pattern

Example 1:

Class service:    def __init__ (self, service_name, process_name,  Port, enable_monitor=none):        self.service_name =  service_name        self.process_name = process_name         self.port = port         self.mon = enable_monitor        self._process_status  = True        self._port_status = True      @property     def process_status (self):         return self._process_status     @process_status .setter     def process_status (Self, status):         self._process_status = status        self.mon.start_mon ()     @ Property    def port_status (self):         return self._port_status     @port_status. Setter    def port_ Status (self, status):         self._port_status = status         self.mon.start_mon () class action:     @classmethod     def send_sms_alarm (cls, content):         print ("sms alarm: {}". Format (content)      @classmethod      def send_email_alarm (cls, content):         print ("email alarm: {}". Format (content)) class monitor:    def __ Init__ (self):        self.services = []    def add_service ( Self, service):         self.services.append (Service)      def start_mon (self):         for ser in  self.services:            if not  ser.process_status:                 action.send_email_alarm ("service: {0} process: {1} status: {2}". Format (                      ser.service_name, ser.process_name, ser.process_status))              if not ser.port_status:                 action.send_email_alarm ("Service: {0} process: {1} status:  {2} ". Format (                     ser.service_name, ser.port, ser.port_status)) if __name__ ==   ' __main__ ':     mon = monitor ()     http =  Service ("http",  "httpd",  80, mon)     mysql = service ("MySQL",   "Mysqld",  3306, mon)     zabbix = service ("Zabbix",  "Zabbixd ",  1501, mon)     mon.add_service (HTTP)     mon.add_service ( MySQL)     mon.add_service (Zabbix)      #mon. Start_mon ()      http.port_status = false

Example 2:

#coding: Utf-8#inventory class describes the warehouse object class inventory:    def __init__ (self):         self.observers = []  #此列表用于存储观察者对象          self._product = None  #产品          self._quantity = 0  #数量     def attach (self, observer):   #此方法用于将观察者对象添加进列表         self.observers.append (Observer)       @property   #使用property装饰器修饰 to turn the method into a property     def product (self):         return self._product     @product. Setter   #使用setter修饰product属性使其可以设置值     def product (self, value):         self._product = value         Self._update_observers ()   #只要设置了产品的值, call the  _update_observers method      @property   #对数量的设置      Def quantity (self):        return self._quantity      @quantity. setter    def quantity (Self, value):         self._quantity = value         Self._update_observers ()   #只要设置了数量的值, call the  _update_observers method     def _update_ Observers (self):         for observer in self.observers:   #遍历观察者对象             observer ()   #直接用 () The Observer object can be called directly because the __call__ method is implemented in the Consoleobserver class #consoleobserver class describes the Observer object class consoleobserver:     def __init__ (self, inventory):         self.inventory = inventory    def __call__ (self):  #实现__call__方法后可直接可调用, the job here is to print the product and quantity information         print ("Product: {0}, quantity: {1}". Format ( self.inventory.product, self.inventory.quantity)) if __name__ ==  ' __main__ ':     i = inventory ()   #创建仓库对象     c = consoleobserver (i)   #创建一个观察者对象, and the warehouse object as the initialization parameter     i.attach (c)   #将观察者对象添加到仓库对象中的observers列表里 (interaction between two objects)     i.product =  widgets   #仓库对象设置产品名称 (with changes)      i.quantity = 5  #仓库对象设置产品数量 (changes)      "     Workflow Analysis:         1, first added a product name, so notify the viewer to print, at this time the newly added product name is printed, the number defaults to 0         2, after the increase in the number of 5, then notify the Observer, at this time to print out the previously added product name and this time a new increase in the number of 5     ' ''

Python design pattern-Observer pattern