作业 —— day17

必做题：

1.编写函数，（函数执行的时间用time.sleep(n)模拟）

import time


def count_time():
    start = time.time()
    time.sleep(2)
    print('我是输出的内容！我要花费零点几毫秒的时间\n')
    stop = time.time()
    print('函数一共运行时间为：', stop - start)


count_time()

2.编写装饰器，为函数加上统计时间的功能

import time


def count_time(func):
    def inner(*args, **kwargs):
        start = time.time()
        func(*args, **kwargs)
        stop = time.time()
        print('函数一共运行时间为：', stop - start)

    return inner


@count_time
def foo():
    time.sleep(2)
    print('我是原封不动的原函数输出的内容！我要花费零点几毫秒的时间')


foo()

3.编写装饰器，为函数加上认证的功能

import time


def identify(func):
    inp_usr = input('请输入用户名：').strip()
    inp_pwd = input('请输入密码：').strip()

    def dealwith():
        if not (inp_usr or inp_pwd):
            print("输入不能为空")
        with open(r'userinfo.txt', mode='at', encoding='UTF-8') as w_register, \
                open(r'userinfo.txt', mode='rt', encoding='UTF-8') as r_register:
            res = r_register.read()
            if inp_usr not in res:
                w_register.write(f'{inp_usr}:{inp_pwd}\n')
                print('注册成功！')
            else:
                print('该用户已存在，注册失败！')

    return dealwith


@identify
def register(name):
    time.sleep(1)
    print('用户{}注册成功！'.format(name))


register()

4.编写装饰器，为多个函数加上认证的功能（用户的账号密码来源于文件），要求登录成功一次，后续的函数都无需再输入用户名和密码

注意：从文件中读出字符串形式的字典，可以用eval('{"name":"egon","password":"123"}')转成字典格式

import time

login_user = {'name': None}


def identify(func):
    def wrapper(*args, **kwargs):
        if login_user['name']:
            return func(*args, **kwargs)
        inp_usr = input('请输入用户名：').strip()
        inp_pwd = input('请输入密码：').strip()
        with open(r'userinfo.txt', mode='rt', encoding='UTF-8') as f:
            for line in f:
                line = line.strip()
                userinfo = eval(line)
                if inp_usr == userinfo['name']:
                    if inp_pwd == userinfo['password']:
                        print('登录成功')
                        login_user['name'] = inp_usr
                        login_user['start_time'] = time.time()
                        return func(*args, **kwargs)
                    else:
                        print('密码错误！')
                        break
            else:
                print('该用户名不存在！')

    return wrapper


@identify
def index1():
    time.sleep(1)
    print('欢迎用户{}来到主页！'.format(login_user['name']))


@identify
def index2():
    time.sleep(1)
    print('欢迎用户{}再一次来到主页！'.format(login_user['name']))


index1()
index2()

5.编写装饰器，为多个函数加上认证功能，要求登录成功一次，在超时时间内无需重复登录，超过了超时时间，则必须重新登录

import time

login_user = {'name': None, 'start_time': 0}


def identify(func):
    def wrapper(*args, **kwargs):
        if login_user['name']:
            spend_time = time.time() - login_user.get('start_time')
            if spend_time < 5:
                return func(*args, **kwargs)
            else:
                print("超时，请重新登录")
                login_user['name'] = None
                login_user['start_time'] = 0
        inp_usr = input('请输入用户名：').strip()
        inp_pwd = input('请输入密码：').strip()
        with open(r'userinfo.txt', mode='rt', encoding='UTF-8') as f:
            for line in f:
                line = line.strip()
                userinfo = eval(line)
                if inp_usr == userinfo['name']:
                    if inp_pwd == userinfo['password']:
                        print('登录成功')
                        login_user['name'] = inp_usr
                        login_user['start_time'] = time.time()
                        return func(*args, **kwargs)
                    else:
                        print('密码错误！')
                        break
            else:
                print('该用户名不存在！')

    return wrapper


@identify
def index1():
    time.sleep(1)
    print('欢迎用户{}来到主页！'.format(login_user['name']))


@identify
def index2():
    time.sleep(1)
    print('欢迎用户{}再一次来到主页！'.format(login_user['name']))


index1()
index2()

选做题：

思考题（选做），叠加多个装饰器，加载顺序与运行顺序，可以将上述实现的装饰器叠加起来自己验证一下

# @deco1 # index=deco1(deco2.wrapper的内存地址)
# @deco2 # deco2.wrapper的内存地址=deco2(deco3.wrapper的内存地址)
# @deco3 # deco3.wrapper的内存地址=deco3(index)
# def index():
#     pass