python基础 No4

装饰器：

装饰器定义：本质就是函数；功能是，为其他函数添加附加功能。（器：函数）       #__iter__()与iter(x)功能一样

原则：1.不修改被修饰函数的源代码；2.不修改被修饰函数的调用方式

装饰器的知识储备：装饰器=高阶函数+函数嵌套+闭包（高阶函数定义：1.函数接收的参数是一个函数名；2.函数的返回值是一个参数名；3.满足上述条件任意之一，都可称之为高阶函数）（函数嵌套：函数内部再定义一个子函数）（闭包：在一个作用域里放入定义变量，相当于打了一个包。闭即封装变量，函数名也是一个变量）

# import time
# def cal(l):
#     start_time=time.time()
#     res=0
#     for i in l:
#         time.sleep(0.05)
#         res+=i
#     stop_time=time.time()                              #对原函数修饰时间，但是修改了源代码
#     print('函数运行时间是%s' %(stop_time-start_time))
#     return res
# print(cal(range(100)))

# import time
# def foo():
#     time.sleep(2)
#     print('你好啊雷师傅')
#
# def test(func):
#     print(func)
#     start_time=time.time()
#     func()
#     stop_time = time.time()         #通过高阶函数接收参数名实现了修饰功能，但改变了调用方式
#     print('函数运行的时间是%s' %(stop_time-start_time))
# test(foo)
# #test函数是高阶，foo函数不是

# import time
# def foo():
#     time.sleep(3)
#     print("from the foo")
# def timer(func):
#     start_time=time.time()
#     func()
#     stop_time = time.time()  # 通过高阶函数返回值为参数名实现了修饰功能，调用方式也没变，但函数会多运行一次
#     print('函数运行的时间是%s' %(stop_time-start_time))
#     return func
# foo = timer(foo)
# foo()

# def father(name):                 #函数嵌套与闭包
#     print('from father %s' %name)
#     def son():
#         name='lytt'
#         print('儿子是%s' %name)
#         def grandson():
#             # name = 'lyttt'
#             print('孙子是%s' %name)
#         grandson()
#     print(locals())                #打印当前的全部局部标量
#     son()
# father('lyt')                      #一个嵌套的函数就相当于一个闭包，闭包封装变量，使用变量时先从自己里面找，没找到再往外找

# #装饰器的架子
# def timmer(func):
#     def wrapper():
#         print(func)
#         func()
#     return wrapper

# import time
# def timmer(func):
#     def wrapper():
#         print(func)
#         start_time=time.time()
#         func()
#         stop_time = time.time()
#         print('运行时间是%s' %(stop_time-start_time))
#     return wrapper
# def test():
#     time.sleep(3)
#     print('test函数运行完毕')
# test = timmer(test)     #获取wrapper地址，这一步也不符合调用方式
# test()

# #原函数无return的终极版本：
# import time
# def timmer(func):
#     def wrapper():
#         # print(func)
#         start_time=time.time()
#         func()
#         stop_time = time.time()
#         print('运行时间是%s' %(stop_time-start_time))
#     return wrapper
# @timmer                     #@timmer相当于test = timmer(test)
# def test():
#     time.sleep(3)
#     print('test函数运行完毕')
# test()

# #原函数有return的终极版本：
# import time
# def timmer(func):
#     def wrapper():
#         # print(func)
#         start_time=time.time()
#         res=func()
#         stop_time = time.time()
#         print('运行时间是%s' %(stop_time-start_time))
#         return res
#     return wrapper
# @timmer                     #@timmer相当于test = timmer(test)
# def test():
#     time.sleep(3)
#     print('test函数运行完毕')
#     return '这是test返回值'
# res=test()
# print(res)

# #原函数有return且有参数的初级版本：
# import time
# def timmer(func):
#     def wrapper(name,age):
#         # print(func)
#         start_time=time.time()
#         res=func(name,age)
#         stop_time = time.time()
#         print('运行时间是%s' %(stop_time-start_time))
#         return res
#     return wrapper
# @timmer
# def test(name,age):
#     time.sleep(3)
#     print('test函数运行完毕，名字是【%s】,年龄是【%s】' %(name,age))
#     return '这是test返回值'
# res=test('lyt',18)
# print(res)

# #原函数有return且有参数的终级版本：
# import time
# def timmer(func):
#     def wrapper(*args,**kwargs):
#         # print(func)
#         start_time=time.time()
#         res=func(*args,**kwargs)
#         stop_time = time.time()
#         print('运行时间是%s' %(stop_time-start_time))
#         return res
#     return wrapper
# @timmer
# def test(name,age,gender):
#     time.sleep(3)
#     print('test函数运行完毕，名字是【%s】,年龄是【%s】性别是【%s】' %(name,age,gender))
#     return '这是test返回值'
# res=test('lyt',18,gender='male')
# print(res)

 

解压序列：

# a,b,c=(1,2,3)     #一个变量对应一个值
# print(a)

# a,*_,c=[10,2,4,7,5,9,2,456,765,4,78]     #取开头和结尾
# print(a,c)

# a,*d,c=[10,2,4,7,5,9,2,456,765,4,78]       #取中间值
# print(d)

# a,b=[1,2]             #ab值互换
# x=a
# a=b
# b=x
# print(a,b)

# f1 = 1                #ab值互换，更简单
# f2 = 2
# f1,f2 = f2,f1
# print(f1,f2)

 

函数闭包为函数加上认证功能

 

# uesr_dic = {'username':None,'login':False}
# def auth_func(func):
#     def wrapper(*args,**kwargs):
#         if uesr_dic['username'] and uesr_dic['login']:
#             res = func(*args, **kwargs)
#             return res
#         username=input('用户名：').strip()
#         passwd=input('密码：').strip()
#         if username == 'lyt' and passwd == '123':
#             uesr_dic['username']=username      #拿的全局变量的引用，改的也就是全局变量
#             uesr_dic['login']=True
#             res=func(*args,**kwargs)
#             return res
#         else:
#             print('用户密码错误，请重新输入')
#             return wrapper(*args,**kwargs)
#     return wrapper
#
# def index():
#     print('欢迎来到xx主页')
#
# @auth_func
# def home(name):
#     print('%s,欢迎回家' %name)
#
# @auth_func
# def shopping_car(name):
#     print('%s购物车里有[%s,%s,%s]' %(name,'奶茶','方便面','书'))
#
# index()
# home('lyt')
# shopping_car('lyt')



#进阶版
# user_dic = [{'name':'ppp','passwd':'123'},{'name':'yyy','passwd':'123'},{'name':'zzz','passwd':'123'},{'name':'mmm','passwd':'123'},{'name':'lyt','passwd':'123'}]#可以用open方式打开文件里的列表
# current_dic = {'username':None,'login':False}
# def auth(auth_type):
#     def auth_func(func):
#         def wrapper(*args,**kwargs):
#             if auth_type=='filedb':
#                 print('验证方式是filedb')
#                 if current_dic['username'] and current_dic['login']:
#                     res = func(*args, **kwargs)
#                     return res
#                 username=input('用户名：').strip()
#                 passwd=input('密码：').strip()
#                 for user_list in user_dic:
#                     if username == user_list['name'] and passwd == user_list['passwd']:
#                         current_dic['username']=username
#                         current_dic['login']=True
#                         res=func(*args,**kwargs)
#                         return res
#                 else:
#                     print('用户密码错误，请重新输入')
#                     return wrapper(*args,**kwargs)
#             elif auth_type=='ssss':
#                 print('以ssss方式认证')
#             elif auth_type=='dddd':
#                 print('以dddd方式运行')
#         return wrapper
#     return auth_func
#
# @auth(auth_type='filedb')          ##执行了两次，得到wrapper地址
# def index():
#     print('欢迎来到xx主页')
#
# @auth(auth_type='ssss')
# def home(name):
#     print('%s,欢迎回家' %name)
#
# @auth(auth_type='filedb')
# def shopping_car(name):
#     print('%s购物车里有[%s,%s,%s]' %(name,'奶茶','方便面','书'))
#
# index()
# home('lyt')
# shopping_car('lyt')

 

一个规范：python文件只写不会运行的功能，要测试运行在（if __name__=='__main__'）下进行

 

三级菜单初识：

#三级菜单：
# while True:                         #分步退出
#     print('level1')
#     a=input('level1>>:')
#     if a=='quit':break
#     while True:
#         print('level2')
#         a = input('level2>>:')
#         if a == 'quit': break
#         while True:
#             print('level3')
#             a = input('level3>>:')
#             if a == 'quit': break

# tag=True                       #可实现一步就结束
# while tag:
#     print('level1')
#     a=input('level1>>:')
#     if a=='quit':break
#     if a=='quit out':tag=False
#     while tag:
#         print('level2')
#         a = input('level2>>:')
#         if a == 'quit': break
#         if a == 'quit out': tag = False
#         while tag:
#             print('level3')
#             a = input('level3>>:')
#             if a == 'quit': break
#             if a == 'quit out': tag = False

 

查询功能：

#__name__ == __main__    相当于一个变量
def fetch(data):
    print('\033[1:43m这是查询功能\033[0m')
    print('\033[1:43m用户数据是\033[0m',data)
    backend_data='backend %s' %data
    with open('haproxy.conf','r')as read_f:
        tag=False
        ret=[]
        for read_line in read_f:
            if read_line.strip() == backend_data:
                tag=True
                continue
            if tag:
                if read_line.startswith('backend'):
                    break
                print('\033[1:43m%s\033[0m' %read_line,end='')
                ret.append(read_line)
    return ret



def add():
    pass

import os
def change(data):
    print('这是修改功能')
    print('用户输入的数据是',data)
    data=eval(data)
    data[0]  #文件当中的一条记录
    data_backend='backend ' + data[0]['backend']
    old_server_recond='%sserver %s %s weight %s maxconn %s\n' %(' '*8,data[0]['recond']['server'],data[0]['recond']['server'],data[0]['recond']['weight'],data[0]['recond']['maxconn'])
    new_server_recond='%sserver %s %s weight %s maxconn %s\n' %(' '*8,data[1]['recond']['server'],data[1]['recond']['server'],data[1]['recond']['weight'],data[1]['recond']['maxconn'])
    print('用户想要修改的数据是%s' %old_server_recond)
    res=fetch(data[0]['backend'])
    # print('来自change函数-->>',res)
    if not res or old_server_recond not in res:
        return '你要修改的数据不存在'
    else:
        index=res.index(old_server_recond)          #找到old_server_recond的索引位置
        # print(index)
        res[index]=new_server_recond
        print(res)
    res.insert(0,'%s\n' %data_backend)
    with open('haproxy.conf','r') as read_f,open('haproxy.conf_new','w') as write_f:
        tag=False
        has_write=False
        for read_line in read_f:
            # print(read_line.strip())
            if read_line.strip() ==data_backend:
                tag=True
                continue
            if tag and read_line.startswith('backend'):
                tag=False
            if not tag:
                write_f.write(read_line)
            else:
                if not has_write:
                    for record in res:
                        write_f.write(record)
                    has_write=True
    os.rename('haproxy.conf','haproxy.conf.bak')
    os.rename('haproxy.conf_new','haproxy.conf')
    os.remove('haproxy.conf.bak')                   #更改文件就是新文件复制并改名



def delete():
    pass

if __name__=='__main__':
    msg='''
    1:查询
    2:添加
    3:修改
    4:删除
    5:退出
    '''

    msg_dic={
        '1':fetch,
        '2':add,
        '3':change,
        '4':delete,
    }

    while True:
        print(msg)
        choice=input('请输入你的选项').strip()              #去两边空格回车，不能去中间的！
        if not choice:continue
        if choice=='5':break

        data=input("请输入你的数据:")
        res=msg_dic[choice](data)
        print(res)

#要修改为的数据[{'backend':'www.oldboy1.org','recond':{'server':'100.1000.7.9','weight':'20','maxconn':'30'}},{'backend':'www.oldboy1.org','recond':{'server':'105.1000.7.9','weight':'20','maxconn':'300'}}]

 

程序解耦：

def file_handler(backend_data,res=None,type='fetch'):
    if type == 'fetch':
        with open('haproxy.conf','r')as read_f:
            tag=False
            ret=[]
            for read_line in read_f:
                if read_line.strip() == backend_data:
                    tag=True
                    continue
                if tag:
                    if read_line.startswith('backend'):
                        break
                    print('\033[1:43m%s\033[0m' %read_line,end='')
                    ret.append(read_line)
        return ret
    elif type == 'change':
        with open('haproxy.conf', 'r') as read_f, open('haproxy.conf_new', 'w') as write_f:
            tag = False
            has_write = False
            for read_line in read_f:
                # print(read_line.strip())
                if read_line.strip() == backend_data:
                    tag = True
                    continue
                if tag and read_line.startswith('backend'):
                    tag = False
                if not tag:
                    write_f.write(read_line)
                else:
                    if not has_write:
                        for record in res:
                            write_f.write(record)
                        has_write = True

def fetch(data):
    print('\033[1:43m这是查询功能\033[0m')
    print('\033[1:43m用户数据是\033[0m',data)
    backend_data='backend %s' %data
    ret = file_handler(backend_data)
    return ret

def add():
    pass

import os
def change(data):
    print('这是修改功能')
    print('用户输入的数据是',data)
    data=eval(data)
    data[0]  #文件当中的一条记录
    backend_data='backend ' + data[0]['backend']
    old_server_recond='%sserver %s %s weight %s maxconn %s\n' %(' '*8,data[0]['recond']['server'],data[0]['recond']['server'],data[0]['recond']['weight'],data[0]['recond']['maxconn'])
    new_server_recond='%sserver %s %s weight %s maxconn %s\n' %(' '*8,data[1]['recond']['server'],data[1]['recond']['server'],data[1]['recond']['weight'],data[1]['recond']['maxconn'])
    print('用户想要修改的数据是%s' %old_server_recond)
    res=fetch(data[0]['backend'])
    # print('来自change函数-->>',res)
    if not res or old_server_recond not in res:
        return '你要修改的数据不存在'
    else:
        index=res.index(old_server_recond)          #找到old_server_recond的索引位置
        # print(index)
        res[index]=new_server_recond
        print(res)
    res.insert(0,'%s\n' %backend_data)
    file_handler(backend_data,res=res,type='change')

    os.rename('haproxy.conf','haproxy.conf.bak')
    os.rename('haproxy.conf_new','haproxy.conf')
    os.remove('haproxy.conf.bak')                   #更改文件就是新文件复制并改名

def delete():
    pass

if __name__=='__main__':
    msg='''
    1:查询
    2:添加
    3:修改
    4:删除
    5:退出
    '''

    msg_dic={
        '1':fetch,
        '2':add,
        '3':change,
        '4':delete,
    }

    while True:
        print(msg)
        choice=input('请输入你的选项').strip()              #去两边空格回车，不能去中间的！
        if not choice:continue
        if choice=='5':break

        data=input("请输入你的数据:")
        res=msg_dic[choice](data)
        print(res)