ha.txt文件内容:

frontend oldboy.org
        bind 0.0.0.0:80
        option httplog
        option httpclose
        option  forwardfor
        log global
        acl www hdr_reg(host) -i www.oldboy.org
        use_backend www.oldboy.org if www

backend www.baidu.org
        server 100.1.7.9 100.1.7.9 weight 20 maxconn 3000
        server 100.1.7.8 100.1.7.8 weight 20 maxconn 4000
backend www.baidu1.com
        server 1.1.1.1 1.1.1.1 weight 20 maxconn 3000

 操作代码ha.py:

import os
#查询
def fetch(data):
    # 把整行作为一个整体,做成字符串拼接
    # 相当于拼接backend www.baidu.com
    #record存放返回的数据
    backend_data = "backend %s" %data
    record_list = []    #定义空列表
    #打开文件
    with open('ha.txt','r',encoding='utf8') as f:
        #在报警期间,一直执行捕捉操作
        tag = False#报警器,默认不响
        for line in f:  #查找backend记录
            #找backend,比较的时候把\n去掉,用sttrip实现
            if line.strip() == backend_data:#找到这行,在去除回车之后,是否等于backend
                tag = True#警报响起
                continue#backend这行不要,跳出本次循环,下次循环都要带着tag警报了
            # 解除警报
            # 警报亮着,并且满足再次匹配backend的时候
            #警报不能放到最后,在抓最后一个人之前,要把警报关闭
            if tag and line.startswith("backend"):
                #tag = False  # 解除警报,但是break之后什么变量都不生效了
                break
            #当tag=True的情况
            #警报亮了,并且有数据进来。line在文件中可能是空行,再加一个and操作
            if tag and line:
                record_list.append(line.strip())#添加数据,每添加一行数据,就循环一次

            #打印用户找到的信息
        for line in record_list:
            print(line)
        return record_list#返回处理的信息




#添加
def add(data):
    backend = data['backend']#获取
    record_list = fetch(backend)#传递给fetch
    #把用户输入的字典转换成server的模式
    current_record = "server %s %s weight %s maxconn %s" %(data['record']['server'], \
                                                                data['record']['server'], \
                                                                data['record']['weight'], \
                                                                data['record']['maxconn'])

    backend_data = "backend %s" %backend#拼接字符串

    #record_list为空的情况下,运行下面的代码
    if not record_list:
        #加入record里面
        record_list.append(backend_data)#标题
        record_list.append(current_record)#server记录
        #打开源文件,打开新文件把源文件内容一行行写入新文件
        with open("ha.txt",'r',encoding="utf-8") as read_file,\
                open("ha_new.txt",'w',encoding='utf-8') as write_file:
            #从源文件一行行读取内容
            for r_line in read_file:
                write_file.write(r_line)#新文件一行行写

            #用户输入的内容
            for new_line in record_list:#读
                if new_line.startswith('backend'):#是backend开头的文件
                    write_file.write(new_line + '\n')#往新文件里写
                else:#其余行
                    write_file.write("%s%s\n" %(" "*8,new_line))#8个空格,写
    else:
        #print(record_list)
        #自己创造一个record_list,把添加的server添加进去,保留原记录
        record_list.insert(0,backend_data)
        if current_record not in record_list:#
            record_list.append(current_record)#添加自己拼接的记录
        #print("new record list %s" %record_list)#新拼接的列表
        with open('ha.txt','r',encoding='utf-8') as read_file,\
                open('ha_new.txt','w',encoding='utf-8') as write_file:
            #警报
            tag = False
            has_write = False
            for r_line in read_file:#源文件读
                if r_line.strip() == backend_data:#拉响警报
                    tag = True
                    continue
                #如果警报是响的并且是匹配到backend的情况
                if r_line.strip() == backend_data:
                    tag = True
                    continue

                if not tag:#警报没有响
                    write_file.write(r_line)#一直往新文件里写
                else:#警报响
                    if not has_write:#如果没有写的情况
                        for new_line in record_list:
                            if new_line.startswith('backend'):
                                write_file.write(new_line + '\n')
                            else:
                                write_file.write('%s%s\n' %(' '*8,new_line))
                        has_write = True#record_list不会写
    os.rename('ha.txt','ha_bak.txt')
    os.rename('ha_new.txt','ha.txt')
    os.remove('ha_bak.txt')
#删除
def remove(data):
    backend = data['backend']
    record_list = fetch(backend)#查
    current_record = "server %s %s weight %s maxconn %s" % (data['record']['server'],\
                                                            data['record']['server'],\
                                                            data['record']['weight'],\
                                                            data['record']['maxconn'])

    backend_data = "backend %s" % backend
    #为空
    if not record_list or current_record not in record_list:
        print("\033[33;1m无此条记录\033[0m")
        return #终止掉
    else:
        #处理record_list,存在,统一处理
        record_list.insert(0,backend_data)#标题加进去
        record_list.remove(current_record)#把用户删除的列表删掉
        with open('ha.txt','r',encoding='utf-8') as read_file,\
                open('ha_new.txt','w',encoding='utf-8') as write_file:
            tag = False
            has_write = False
            for r_line in read_file:
                if r_line.strip() == backend_data:
                    tag = True
                    continue
                if tag and r_line.startswith('backend'):
                    tag = False
                if not tag:
                    write_file.write(r_line)
                else:
                    if not has_write:
                        for new_line in record_list:
                            if new_line.startswith('backend'):
                                write_file.write(new_line + '\n')
                            else:
                                write_file.write('%s%s\n' %(' '*8,new_line))
                        has_write = True
    os.rename('ha.txt','ha_bak.txt')
    os.rename('ha_new.txt','ha.txt')
    os.remove('ha_bak.txt')

def change(data):
    #通过列表找到backend信息
    backend = data[0]['backend']
    record_list = fetch(backend)#找到backend信息

    #改的数据,旧内容,新内容
    old_record = "server %s %s weight %s maxconn %s" % (data[0]['record']['server'], \
                                                        data[0]['record']['server'], \
                                                        data[0]['record']['weight'], \
                                                        data[0]['record']['maxconn'])

    new_record = "server %s %s weight %s maxconn %s" % (data[1]['record']['server'], \
                                                        data[1]['record']['server'], \
                                                        data[1]['record']['weight'], \
                                                        data[1]['record']['maxconn'])

    backend_data = "backend %s" % backend

    #没有backend或者server信息不存在
    if not record_list or old_record not in record_list:
        print('\033[33;1m无此内容\033[0m')
        return
    else:
        record_list.insert(0,backend_data)#重新生成record_list
        index=record_list.index(old_record)#旧内容索引
        record_list[index]=new_record#替换
        with open('ha.txt', 'r', encoding='utf-8') as read_file, \
                open('ha_new.txt', 'w', encoding='utf-8') as write_file:
            tag = False
            has_write = False
            for r_line in read_file:
                if r_line.strip() == backend_data:
                    tag = True
                    continue
                if tag and r_line.startswith('backend'):
                    tag = False
                if not tag:
                    write_file.write(r_line)
                else:
                    if not has_write:
                        for new_line in record_list:
                            if new_line.startswith('backend'):
                                write_file.write(new_line + '\n')
                            else:
                                write_file.write('%s%s\n' % (' ' * 8, new_line))
                        has_write = True
    os.rename('ha.txt', 'ha_bak.txt')
    os.rename('ha_new.txt', 'ha.txt')
    os.remove('ha_bak.txt')


#代码运行的时候就会把__name__赋值给__main__
#如果把代码当做模块导入,__name__就会被赋值为文件名
if __name__ == '__main__':#系统内置变量
    #用户提示信息
    msg = '''
    1:查询-fetch
    2:添加-add
    3:删除-remove
    4:修改-change
    5:退出-exit
    '''
    #定义字典,实现提示信息与上面函数的对应关系,数字:函数名,不能加(),加上就是运行结果
    #key定义成字符串的形式
    menu_dic = {
        '1':fetch,
        '2':add,
        '3':remove,
        '4':change,
        '5':exit
    }
    #死循环,不断的跟用户去交互
    #主逻辑
    while True:
        print(msg)
        choice=input("操作>>:").strip()#用户选择
        if choice == '2' or choice == '3':
            print("实例:{'backend':'www.baidu1.com','record':{'server':'2.2.2.2','weight':20,'maxconn':3000}}")
        if choice == '4':
            print("实例(旧内容,新内容):[{'backend':'www.baidu1.com','record':{'server':'1.1.1.1','weight':20,'maxconn':3000}},{'backend':'www.baidu1.com','record':{'server':'2.2.2.2','weight':20,'maxconn':4000}}]")
        #用户为空 or 用户超过可选范围
        if len(choice) == 0 or choice not in menu_dic:continue#不在里面
        if choice == '5':break

        #在用户输入完操作选项之后,输入
        #data输入完之后,要把数据传入到上面的一个个功能,就是在函数名的地方加上data
        #所以上面的所有函数都要有参数,在函数名的()内都要加上data

        #用户输入的是字典的话,转换成字符串赋值给data
        data = input("数据>>:").strip()

        #如果用户输入不是1查询的话,因为默认是字符串的模式,所以要加引号
        if choice != '1':
            #在下面执行的时候,再通过eval转换成字典,最后赋值给add,或者del功能
            data = eval(data)#把用户输入的字符串转换成字符串原本包含的格式,最终赋值给data

        #用户执行操作
        #menu_dic[choice]==fetch
        #menu_dic[choice]() == fetch()
        # menu_dic[choice](data) == fetch(data)
        #定义一个字典,通过字典的方式调用一个函数,这样函数名有变动,只要改字典的对应关系就可以了,这样主逻辑就不用动了
        menu_dic[choice](data)

 

posted on 2016-11-03 16:54  Beirut  阅读(614)  评论(0编辑  收藏  举报