Python 文件读写，条件循环（三次登录锁定账号实例）

通过文件读写，条件循环相关语法，实现三次登录失败则锁定该账号的功能

需求一

"""
需求描述：
    1.输入正确账号，密码，退出程序
    2.登录失败，重新输入账号密码
    3.同一账号连续登录失败超过三次，则锁定该账号
    4.登录已锁定账号，提示账号已锁定
"""

流程图一

实例代码一

#!/usr/bin/python
#coding=utf-8

"""
需求描述：
    1.输入正确账号，密码，退出程序
    2.登录失败，重新输入账号密码
    3.同一账号连续登录失败超过三次，则锁定该账号
    4.登录已锁定账号，提示账号已锁定
user.txt:
    Milton Loveyp 0
    Cherish Loveypgfc 0
    yangp Loveypgfc 0
"""

def modify_user(name, mode="add"):
    """
    修改用户名单中的登录错误次数
    :param name: 用户名称
    :param mode:add，登录错误次数自增1；del，登录错误次数重置为0
    :return:
    """

    # 读取用户文件
    with open("user.txt", "r") as read_file:
        read_data = read_file.readlines()

    # 写入用户文件
    with open("user.txt", "w") as write_file:
        for line in read_data:
            new_line = line.split()
            if new_line[0] == name:
                if mode == "add":
                    new_line[2] = bytes(int(new_line[2]) + 1)
                else:
                    new_line[2] = ""
                new_line = " ".join(new_line) + "\n"
                write_file.write(new_line)
                write_file.flush()
            else:
                write_file.write(line)

def auth(name, passwd):
    """
    用户鉴权
    :param name: 登录用户名
    :param passwd: 登录密码
    :return:
    """
    with open("user.txt", "r") as read_file:
        for eachLine in read_file:
            user_name, password, errors = eachLine.split()
            if name == user_name:
                if int(errors) < 3:
                    if password == passwd:
                        print "Dear [%s],welcome~" % name
                        modify_user(name, "del")
                        return True
                    else:
                        print "auth fail,please check your account and password!"
                        modify_user(name, "add")
                        return False
                else:
                    print "your accout is locked!"
                    return False
        else:
            print "your account is not exist!"
            return False

def login():
    """
    登录
    :return:
    """
    while True:
        name = raw_input("Name:")
        passwd = raw_input("PASS:")
        if auth(name, passwd):
            break

if __name__ == '__main__':
    login()

需求二，在一的基础上添加锁定时间控制。

"""
需求点：
    1.用户输入账号与密码
    2.如果输入正确，则提示欢迎信息
    3.如果输入账号不存在，则提示账号不存在
    4.如果输入账号与密码不匹配，提示验证失败
    5.同一账号，如果连续输入三次错误密码，则锁定该账号2min，2min后重新输入，如果账号密码匹配，则登录成功
    6.如果三次登录内成功登录，则清空登录错误次数
    7.登录时，如果账号已被锁定，提示账号已锁定信息
"""

流程图二

实例代码二

#!/usr/bin/env python
# -*- coding: utf-8 -*-

"""
需求点：
    1.用户输入账号与密码
    2.如果输入正确，则提示欢迎信息
    3.如果输入账号不存在，则提示账号不存在
    4.如果输入账号与密码不匹配，提示验证失败
    5.同一账号，如果连续输入三次错误密码，则锁定该账号2min，2min后重新输入，如果账号密码匹配，则登录成功
    6.如果三次登录内成功登录，则清空登录错误次数
    7.登录时，如果账号已被锁定，提示账号已锁定信息
user.txt:
    Milton Loveyp 0
    Cherish Loveypgfc 0
    yangp Loveypgfc 0
"""

import time

def modify_user(name, mode="add"):
    """
    修改用户名单中的登录错误次数
    :param name: 用户名称
    :param mode:add，登录错误次数自增1；del，登录错误次数重置为0
    :return:
    """
    # 读取用户文件
    with open("user.txt", "r") as read_file:
        read_data = read_file.readlines()

    # 写入用户文件
    with open("user.txt", "w") as write_file:
        for line in read_data:
            new_line = line.split()
            if new_line[0] == name:
                if mode == "add":
                    new_line[2] = bytes(int(new_line[2]) + 1)
                    if len(new_line) < 4:
                        new_line.append(str(time.time()))
                    else:
                        new_line[3] = str(time.time())
                else:
                    new_line[2] = ""
                    new_line = new_line[0:3]
                new_line = " ".join(new_line) + "\n"
                write_file.write(new_line)
                write_file.flush()
            else:
                write_file.write(line)

def auth(name, passwd, lock_time):
    """
    用户鉴权
    :param name: 登录用户名
    :param passwd: 登录密码
    :return:
    """
    with open("user.txt", "r") as read_file:
        for eachLine in read_file:
            user_list = eachLine.split()
            if len(user_list) < 4:
                user_list.append(str(time.time() - 100000))
            user_name, password, errors, last_time = user_list

            if name == user_name:
                if password == passwd:
                    if time.time() - float(last_time) > lock_time or int(errors) < 3:
                        print "Dear [%s],welcome~" % name
                        modify_user(name, "del")
                        return True
                    else:
                        print "your accout is locked,please try after [%f]s !" % (
                            lock_time - (time.time() - float(last_time)))
                        return False
                else:
                    if int(errors) < 3:
                        print "auth fail,please check your account and password!"
                        modify_user(name, "add")
                        return False
                    elif time.time() - float(last_time) > lock_time:
                        print "auth fail,please check your account and password!"
                        modify_user(name, "del")
                        modify_user(name, "add")
                        return False
                    else:
                        print "your accout is locked,please try after [%f]s !" % (
                            lock_time - (time.time() - float(last_time)))
                        return False
        else:
            print "your account is not exist!"
            return False

def login():
    """
    登录
    :return:
    """
    while True:
        user_name = raw_input("Name:")
        pwd = raw_input("PASS:")
        if auth(user_name, pwd, 120):
            break

if __name__ == '__main__':
    login()