文件查询修改功能实现

import os

def futch(data):
    # print('这里是查询功能')
    # print('要查询的数据是：',data)
    backend_data = 'backend %s' % data
    with open('haproxy.conf', 'r') as read_f:
        tag = False
        result = []
        for read_line in read_f:
            if read_line.strip() == backend_data:
                tag = True
                continue
            if tag and read_line.startswith('backend'):
                # tag=False
                break
            if tag:
                # print(read_line,end='')
                result.append(read_line)
    return result


def add():
    print('这里是添加功能')


def change(data):
    # print('这里是修改功能')
    # print('想要修改的是：',date)
    backend = data[0]['backend']  # backend=www.oldboy1.org
    backend_data = 'backend %s' % backend
    # print(backend)
    old_server_record = '%sserver %s weight %s maxconn %s
' % (' ' * 8,
                                                                data[0]['record']['server'],
                                                                data[0]['record']['weight'],
                                                                data[0]['record']['maxconn']
                                                                )
    new_server_record = '%sserver %s weight %s maxconn %s
' % (' ' * 8,
                                                                data[1]['record']['server'],
                                                                data[1]['record']['weight'],
                                                                data[1]['record']['maxconn']
                                                                )
    # print('用户想要修改的数据是：',old_server_record)
    # print('用户想要改成的数据是：', new_server_record)
    result = futch(backend)
    # print(result)
    if not result or old_server_record not in result:
        print('未找到想要修改的数据')
    index = result.index(old_server_record)
    result[index] = new_server_record
    # print(result)
    result.insert(0, '%s
' % backend_data)
    # print(result)
    with open('haproxy.conf', 'r') as read_f, 
            open('haproxy.conf_new', 'w') as write_f:
        tag = False
        write_tag = False
        for read_line in read_f:
            if read_line.strip() == backend_data:
                tag = True
                continue
            if tag and read_line.startswith('backend'):
                tag = False
            if not tag:
                write_f.write(read_line)
            else:
                if not write_tag:
                    for record in result:
                        write_f.write(record)
                    write_tag = True


def delete():
    print('这里是删除功能')


if __name__ == '__main__':
    masage = '''
           1:查询
           2:添加
           3:修改
           4:删除
           5:退出
           '''
    masage_dic = {
        '1': futch,
        '2': add,
        '3': change,
        '4': delete
    }

    while 'True':
        print(masage)
        choice = input('请输入你的选项：').strip()
        if not choice:
            continue
        if choice == '5':
            break
        data = input('请输入数据：').strip()
        if choice != '1':
            data = eval(data)
        res = masage_dic[choice](data)
        print(res)

# [{'backend':'www.oldboy1.org','record':{'server':'2.2.2.5 2.2.2.5','weight':'30','maxconn':'4000'}},{'backend':'www.oldboy1.org','record':{'server':'2.2.2.4 2.2.2.4','weight':'30','maxconn':'4000'}}]