【python之路33】开发模式单例模式

#!usr/bin/env python
# -*- coding:utf-8 -*-
class ConnecttionPool:
    __instance = None
    def __init__(self):
        self.ip = ‘222.133.177.67‘
        self.port = ‘3306‘
        self.username = ‘odoo‘
        self.password = ‘123456‘

        self.con_list = [1,2,3,4,5,6,7,8,9,10]
    @staticmethod
    def get_instance():  #创建实例的方法
        if ConnecttionPool.__instance:
            return ConnecttionPool.__instance
        else:
            ConnecttionPool.__instance = ConnecttionPool()
            return ConnecttionPool.__instance
    def get_connection(self):
        #获得连接
        import random
        r = self.con_list[random.randrange(1,10)]
        return r

for i in range(10):
    pool = ConnecttionPool.get_instance()
    print(‘去连接池‘,pool,‘获得一个连接‘)
    r = pool.get_connection()
    print(‘获得的连接是：‘,r)

#!usr/bin/env python
# -*- coding:utf-8 -*-
from wsgiref.simple_server import make_server

def RunServer(environ,start_response):
    start_response(status=‘200 OK‘,headers=[(‘Content-Type‘,‘text/html‘)])
    url = environ[‘PATH_INFO‘]  #url取的是访问时端口号后面的地址
    return ‘谢谢你的访问！‘  #可以读取html文件


if __name__ == ‘__main__‘:
    httpd = make_server(‘‘,8000,RunServer)
    print(‘Server Http on 8000......‘)
    httpd.serve_forever()  #循环监听访问，当有访问时，返回RunServer函数的返回值