python_day021 some common modules and files about time and random

1.函数解耦，fetch()和change()函数中均用到文件处理的操作，所以定义file_handler()做统一处理，防止fetch和change中都夹杂文件处理的内容，增强代码的可读性和维护性

#!user/bin/env python
# -*- coding:utf-8 -*-
import os
def file_handler(backend_data,res=None,type='fetch'):  #位置参数在左，默认参数在右
    # print(backend_data)
    if type == 'fetch':
        with open('haproxy.conf','r') as read_f:
            li = []
            tag = False
            for read_line in read_f:
                # print(read_line)
                if read_line.strip() == backend_data:
                    tag = True
                    continue
                if tag and read_line.startswith('backend'): #找到backend 并且 下一行以backend开头(加上tag防止在目标行之前先找到backend)
                    break
                if tag:
                    print('\033[1;45m%s\033[0m' %read_line,end='')
                    li.append(read_line)
        return li
    elif type == 'change':
        with open('haproxy.conf', 'r') as \
                read_f, open('haproxy_new.conf', 'w') as write_f:
            tag = False
            has_writen_tag = False
            for read_line in read_f:
                if read_line.strip() == backend_data:
                    tag = True
                    # write_f.write(read_line)
                    continue
                if tag and read_line.startswith('backend'):
                    tag = False
                if not tag:
                    write_f.write(read_line)
                else:
                    if not has_writen_tag:
                        for record in res:
                            write_f.write(record)
                        has_writen_tag = True
        os.rename('haproxy.conf', 'haproxy.conf.bak')  # 对haproxy.conf文件重新命名为haproxy.conf.bak
        os.rename('haproxy_new.conf', 'haproxy.conf')  # 对haproxy_new.conf重新命名为haproxy.conf
        os.remove('haproxy.conf.bak')  # 移除.bak文件
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
    return file_handler(backend_data)
def add():
    pass
def change(data):
    # print('这是修改功能')
    print('用户输入的数据是',data)
    backend = data[0]['backend'] #文件中的一条记录 查找1 www.oldboy1.org
    backend_data = 'backend %s'%backend #backend www.oldboy1.org
    #        server 2.2.2.4 2.2.2.4 weight 20 maxconn 3000
    #        server 2.2.2.5 2.2.2.5 weight 30 maxconn 4000
    # [{'backend':'www.oldboy1.org','record':{'server':'2.2.2.4','weight':20,'maxconn':3000}},{'backend':'www.oldboy1.org','record':{'server':'2.2.2.5','weight':30,'maxconn':4000}}]
    old_server_record = '%sserver %s %s weight %s maxconn %s\n'%(' '*8,data[0]['record']['server'],
                                                                data[0]['record']['server'],
                                                                data[0]['record']['weight'],
                                                                data[0]['record']['maxconn'])
    new_server_record = '%sserver %s %s weight %s maxconn %s\n'%(' '*8,data[1]['record']['server'],
                                                                data[1]['record']['server'],
                                                                data[1]['record']['weight'],
                                                                data[1]['record']['maxconn'])
    print('用户想要修改的记录是',old_server_record)   #查找2{'server':'2.2.2.4','weight':20,'maxconn':3000}
    res = fetch(backend) #fetch('www.oldboy1.org')
    # print('来自查找函数',res)
    print('来自修改函数--->',res)
    if not res or old_server_record not in res:
        print('修改记录不存在')
    else:
        index = res.index(old_server_record)
        res[index] = new_server_record
    res.insert(0,'%s\n' %backend_data)
    file_handler(backend_data,res=res,type='change')

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,
        '5':exit
    }
    bool = True
    while bool:
        print(msg)
        choice = input('please input your item:')
        if not choice:continue
        if choice == '5':break
        data = input('请输入你的数据:')
        if data == '':
            continue
        if choice != '1':
            data = eval(data)
        res = msg_dic[choice](data)
        print(res)