作业day16

2020-06-22

1、编写课上讲解的有参装饰器

def auth(mode):
    def outer(func):
        def wrapper(*args, **kwargs):
            while True:
                inp_name = input("请输入您的用户名：")
                inp_pwd = input("请输入您的密码：")
                if mode == 'file':
                    print('approve from file')
                    with open('info.db', mode='r', encoding='utf-8') as f:
                        for line in f:
                            name_db, pwd_db = line.strip('
').split(':')
                            if inp_name == name_db and inp_pwd == pwd_db:
                                print('login success')
                                res = func(*args, **kwargs)
                                return res
                        else:
                            print('login error')
                elif mode == 'mysql':
                    print("approve from mysql")
                    res = func(*args, **kwargs)
                    return res
                elif mode == "ldap":
                    print('approve from ldap')
                    res = func(*args, **kwargs)
                    return res
                else:
                    print('mode error')

        return wrapper

    return outer


@auth('mysql')
def index(x, y):
    print(x, y)
    return 123


res = index(1, 2)
print(res)

2.  还记得我们用函数对象的概念，制作一个函数字典取代多分支if的操作吗，来来来，我们有更高大上的做法，

     在文件开头声明一个空字典，然后在每个函数前加上装饰器，完成自动添加到字典的操作

dic = {}


def outer(func):
    def wrapper(*args, **kwargs):

        res = func(*args, **kwargs)
        l1 = []

        for v in dic.values():
            l1.append(v)
        if func not in l1:
            dic[str(len(dic) + 1)] = res
        return res

    return wrapper


@outer
def login():
    print('登录功能')
    return '登录', login


login()


@outer
def register():
    print('注册功能')
    return '注册', register


register()


@outer
def transfer():
    print('转账功能')
    return '转账', transfer


transfer()


@outer
def charge():
    print('充值')
    return '充值', charge


charge()


@outer
def withdraw():
    print('提现')
    return '提现', withdraw


withdraw()
print(dic)

3、 编写日志装饰器，实现功能如：一旦函数f1执行，则将消息2017-07-21 11:12:11 f1 run写入到日志文件中，日志文件路径可以指定=》有参装饰器

注意：时间格式的获取
import time
time.strftime('%Y-%m-%d %X')

import time


def outer2(mode):
    def outer(func):
        def wrapper(*args, **kwargs):
            if mode == 'file':
                with open('access.log', mode='at', encoding='utf-8')as f:
                    f.write("%s %s run
" % (time.strftime('%Y-%m-%d %X'), func.__name__))
            res = func(*args, **kwargs)
            return res

        return wrapper

    return outer


@outer2('file')
def index(x):
    print(x)


index(10)

4、基于迭代器的方式，用while循环迭代取值字符串、列表、元组、字典、集合、文件对象

　　字符串：

msg = 'hello'
msg_iter = iter(msg)
while True:
    try:
        item = next(msg_iter)
        print(item)
    except StopIteration:
        break

　　列表：

l1 = [1,2,3,4]
l1_iter = iter(l1)
while True:
    try:
        item = next(l1_iter)
        print(item)
    except StopIteration:
        break

　　元组：

t1 = (1, 2, 3, 4, 5)
t1_iter = iter(t1)
while True:
    try:
        item = next(t1_iter)
        print(item)
    except StopIteration:
        break

　　字典：

dic = {'k1': 'aaa', 'k2': 'bbb', 'k3': 'ccc'}
dic_iter = iter(dic)
while True:
    try:
        k = next(dic_iter)
        print(k, dic[k])
    except StopIteration:
        break

　　集合：

set = {111, 222, 333, 444}
set_iter = iter(set)
while True:
    try:
        item = next(set_iter)
        print(item)
    except StopIteration:
        break

　　文件对象：

with open('info.db', 'r', encoding='utf-8') as f:
    f_iter = iter(f)
    while True:
        try:
            line = next(f_iter)
            print(line, end="")
        except StopIteration:
            break

 选做作业：

编写小说阅读程序实现下属功能
一：程序运行开始时显示
0 账号注册
1 充值功能
2 阅读小说

二： 针对文件db.txt，内容格式为："用户名:密码:金额",完成下述功能
2.1、账号注册
2.2、充值功能

三：文件story_class.txt存放类别与小说文件路径，如下,读出来后可用eval反解出字典
{"0":{"0":["倚天屠狗记.txt",3],"1":["沙雕英雄转.txt",10]},"1":{"0":["令人羞耻的爱.txt",6],"1":["二狗的妻子与大草原的故事.txt",5]},}

3.1、用户登录成功后显示如下内容，根据用户选择，显示对应品类的小说编号、小说名字、以及小说的价格
"""
0 玄幻武侠
1 都市爱情
2 高效养猪36技
"""

3.2、用户输入具体的小说编号，提示是否付费，用户输入y确定后，扣费并显示小说内容，如果余额不足则提示余额不足

四：为功能2.2、3.1、3.2编写认证功能装饰器，要求必须登录后才能执行操作

五：为功能2.2、3.2编写记录日志的装饰器，日志格式为："时间 用户名 操作(充值or消费) 金额"

import os
import time
from functools import wraps

login_user = None 
change_money = 0
func1 = None

print('0 账号注册',
      '1 充值功能',
      '2 阅读小说')

def register():  # 注册
    tag = True
    while tag:
        inp_name = input("请注册您的用户名：").strip()
        with open('db.txt', mode='r+t', encoding='utf-8') as f:
            l = []
            for line in f:
                name, *_ = line.strip('
').split(":")
                l.append(name)
            if inp_name not in l:
                while True:
                    inp_pwd = input("请注册您的数字密码：").strip()
                    if inp_pwd.isdigit():
                        re_pwd = input("请确认您的数字密码：").strip()
                        if inp_pwd == re_pwd:
                            f.seek(0, 2)
                            f.write("%s:%s:0
" % (inp_name, inp_pwd))
                            tag = False
                            break
                        else:
                            print("两次输入不一致，请重新输入")
                    else:
                        print("格式有误，请重新注册密码")
            else:
                print('您输入的用户名已存在')


def outer(func):  # 登录认证装饰器
    @wraps(func)
    def wrapper1(*args, **kwargs):
        tag = True
        while tag:
            inp_name = input('请输入您的用户名：')
            inp_pwd = input('请输入您的密码：')
            with open('db.txt', mode='r', encoding='utf-8') as f:
                for line in f:
                    user_name, pwd, money = line.strip('
').split(":")

                    if inp_name == user_name and inp_pwd == pwd:
                        print("登录成功！")
                        global login_user
                        login_user = inp_name
                        tag = False
              
        res = func(*args, **kwargs)
        return res

    return wrapper1


def monitor(func):  # 日志装饰器
    @wraps(func)
    def wrapper2(*args, **kwargs):
        start_time = time.strftime('%Y-%m-%d %H-%M-%S')
        res = func(*args, **kwargs)
        with open('access.log', mode='a', encoding='utf-8') as f:
            f.write("{} {}{}{}元
".format(start_time, login_user, '充值了' if func1 == charge else '消费了', change_money))
           
        return res

    return wrapper2


@outer
@monitor
def charge(user, add_money):  # 充值
    with open('db.txt', mode='r', encoding='utf-8') as f:
        for line in f:
            if user in line:
                old_line = line
                old_data = line.strip('
').split(':')

                if add_money > 0:
                    old_data[2] = str(int(old_data[2]) + add_money)
                    new_line = ':'.join(old_data) + '
'

                    f.seek(0, 0)
                    res = f.read().replace(old_line, new_line)

                    global change_money
                    change_money = add_money
                    global func1
                    func1 = charge
                else:
                    print('金额不得小于0')
                    return

    with open('new_db.txt', mode='w', encoding='utf-8') as p:
        p.write(res)

    os.remove('db.txt')
    os.renames('new_db.txt', 'db.txt')

@outer
@monitor
def reading():  # 购买小说
    with open('story_class.txt', mode='r', encoding='utf-8') as f:
        dic = eval(f.read())

    print("""0 玄幻武侠
1 都市爱情
2 高效养猪36技""")

    while True:

        cmd = input('请输入您想看的类别编号：').strip()

        if cmd not in ['0', '1', '2']:
            print('您输入的编号不存在，请重新输入')
        else:
            for k, v in dic[cmd].items():
                print('%s %s price: %s' % (k, v[0], v[1]))  # 目录价格

            tag = True
            while tag:  # 购买
                num = input("请选择需要购买的书籍：").strip()
                if num in dic[cmd]:
                    inp_cmd = input('请确认购买（确认输入"y",否则输入"n"）：').strip()
                    if inp_cmd == 'y':  # 确认购买
                        with open('db.txt', mode='r', encoding='utf-8') as f, 
                                open(r'new_db.txt', mode='w', encoding='utf-8') as p:
                            for line in f:
                                if login_user in line:
                                    old_line = line
                                    old_info = line.strip('
').split(':')
                                    money = int(old_info[-1])
                                    if money < dic[cmd][num][-1]:
                                        print('当前余额不足')
                                        return
                                    else:
                                        money -= dic[cmd][num][-1]

                                        global change_money
                                        change_money = dic[cmd][num][-1]
                                        global func1
                                        func1 = reading
                                        old_info[-1] = str(money)
                                        new_line = ':'.join(old_info) + '
'
                                        f.seek(0, 0)
                                        res = f.read().replace(old_line, new_line)
                                        p.write(res)
                                        tag = False
                        os.remove('db.txt')
                        os.renames('new_db.txt', 'db.txt')
                        with open(dic[cmd][num][0], mode='r', encoding='utf-8') as f1:  # 显示小说内容
                            data = f1.read()
                            print(data)
                            return
                else:
                    return