import os                                                       #导入os模块
def search():                                                   #定义查找函数
    with open(‘haproxy.txt‘,‘r‘) as f:                        #只读方式打开文件
        value = http://www.mamicode.com/input(‘请输入您要查询的信息:‘)
        backend = ‘backend %s‘ % value                         #字符串拼接
        records = []                                             #定义空列表
        tag = False                                             #将标签设置为false
        for line in f:                                           #循环打开文件
            if line.strip() == backend:                          #当line等于backend，将标签改为true
                tag = True
                continue                                         #跳出当前循环
            if line.startswith(‘backend‘):                       #当line以backend开头，跳出整个循环
                break
            if tag == True:                                      #标签为true，将line去除首尾空值，加入到records列表中
                records.append(line.strip())
        print(records)                                             #打印列表

def add():                                                        #定义add函数
    adds = input(‘请输入你要添加的内容：‘)
    adds = eval(adds)                                               #将adds转换为集合
    backend = ‘\nbackend %s \n‘ % adds[‘backend‘]                   #拼接字符串
    record = ‘        server {server} {server} weight {weight} maxconn {maxconn}\n‘.format(
            server = adds[‘record‘][‘server‘],
            weight = adds[‘record‘][‘weight‘],
            maxconn = adds[‘record‘][‘maxconn‘]
            )
    records =[]                                                     #定义records空列表
    with open(‘haproxy.txt‘,‘r‘) as r_file,\ 
            open(‘haproxy_add.txt‘,‘w+‘) as w_file:             #只读方式打开haproxy，生成新文件haproxy_add
        tag = True                                                  #标签设置为true
        for r_line in r_file:                                       #循环文件
            if r_line.strip() == backend.strip():  #当两个值相等，
                tag = False                        #将标签设为false             
                records = r_file.readlines()        #并将这一行的后面所有值加入到records列表中
                w_file.write(backend)               #将backend写入新文件
                break                               #跳出for循环
            w_file.write(r_line)          #将r_line写入新文件
        if tag == True:                           #当tag为true时
            w_file.write(backend)                  #写入backend和record
            w_file.write(record)
        if tag == False:                           #当tag为false时
            if record not in records:              #如果record不在records列表内
                records.insert(0,record)            #把record的值加入到列表的第一个位置
            for line in records:                    #遍历records列表
                w_file.write(line)                   #将列表的值写入到新文件
    os.rename(‘haproxy.txt‘,‘haproxy.addbak‘)     #将文件备份
    os.rename(‘haproxy_add.txt‘,‘haproxy.txt‘)


def remove():                                           #定义remove函数
    removes = input(‘请输入你要删除的内容：‘)
    removes = eval(removes)                                  #将removes转换为集合
    backend = ‘\nbackend %s\n‘ % removes[‘backend‘]            #拼接字符串
    record = ‘        server {server} {server} weight {weight} maxconn {maxconn}\n‘.format(
            server = removes[‘record‘][‘server‘],
            weight = removes[‘record‘][‘weight‘],
            maxconn = removes[‘record‘][‘maxconn‘]
            )
    with open(‘haproxy.txt‘,‘r‘) as r_file,\             
            open(‘haproxy_remove.txt‘,‘w+‘) as re_file:   #只读方式打开haproxy，生成新文件haproxy_remove
            tag = True                                  #定义标签为True
            for r_line in r_file:                           #遍历文件
                if  backend.strip() == r_line.strip() or r_line.strip() == record.strip():
                    tag = False                            #当两个字符串有一个等于r_line时，将标签改为false
                    continue                                #跳出当前循环
                if r_line.startswith(‘backend‘) or r_line.strip() != record.strip():
                    tag = True                          #当r_line开头为backend或者record不等于r_line时，将标签改为true
                if tag == True:                         #当标签为true，写入新文件
                    re_file.write(r_line)
    os.rename(‘haproxy.txt‘,‘haproxy.removbak‘)             #备份文件
    os.rename(‘haproxy_remove.txt‘,‘haproxy.txt‘)

def alter():                                               #定义alter函数
    alters = input(‘请输入你要修改的原的内容：‘)
    alters_new = input(‘请输入你要修改的新内容：‘)
    alters = eval(alters)                                   #将两个值转为字典
    alters_new = eval(alters_new)
    backend = ‘\nbackend %s\n‘ % alters[‘backend‘]              #拼接字符串
    record = ‘        server {server} {server} weight {weight} maxconn {maxconn}\n‘.format(
        server=alters[‘record‘][‘server‘],
        weight=alters[‘record‘][‘weight‘],
        maxconn=alters[‘record‘][‘maxconn‘]
    )
    backends = ‘\nbackend %s\n‘ % alters_new[‘backend‘]
    records = ‘        server {server} {server} weight {weight} maxconn {maxconn}\n‘.format(
        server=alters_new[‘record‘][‘server‘],
        weight=alters_new[‘record‘][‘weight‘],
        maxconn=alters_new[‘record‘][‘maxconn‘]
    )
    with open(‘haproxy.txt‘, ‘r‘) as r_file, \       
            open(‘haproxy_alter.txt‘, ‘w+‘) as al_file:     #只读方式打开haproxy，生成新文件haproxy_alter
        for r_line in r_file:                           #遍历文件
            if backend.strip() == r_line.strip():               #当原值为输入的原值，修改为新值
                r_line = r_line.replace(backend,backends)
            if  r_line.strip() == record.strip():
                r_line = r_line.replace(record,records)
            al_file.write(r_line)                      #写入新文件
    os.rename(‘haproxy.txt‘,‘haproxy.alterbak‘)        #备份文件
    os.rename(‘haproxy_alter.txt‘,‘haproxy.txt‘)


menu = [‘1.查找‘,‘2.新增‘,‘3.删除‘,‘4.修改‘,‘q.退出‘]    #定义菜单
menu_func = {‘1‘:search,                                     #定义功能字典
             ‘2‘:add,
             ‘3‘:remove,
             ‘4‘:alter,
}
while True:                                               #开始循环
    print(‘-----------------------------------‘)
    for i in menu:                                         #打印菜单
        print(i)
    choise = input(‘请选择您的操作方式(输入对应编号)：‘)
    if choise.isdigit():                                        #判断输入是否为数字
        if int(choise) <= len(menu_func) and int(choise) >0:    #判断输入数字是否在菜单内
            menu_func[choise]()                                 #调用功能字典内对应数字的函数
        else:                                                   #为数字但不再菜单内，提示
            print(‘请输入对应的编号!\n‘)
    elif choise == ‘q‘:                                         #输入q退出
        print(‘退出成功!‘)
        break
    else:                                                   #不为数字提示
        print(‘请输入对应的编号!\n‘)




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haproxy文件操作