自动更新公网域名的解析（阿里云）

python脚本，检测主机Wlan的ip地址，对比本地sqlist和阿里云dns，有变化则更新。
定时更新centos主机wlan网卡获取的动态ip到--阿里云域名testhost.localnetwork.cn，实现类似ddns功能
注：将脚本内演示密钥和服务器所在地区换成自己的

```shell
pip3 install aliyun-python-sdk-core
pip3 install aliyun-python-sdk-domain
pip3 install aliyun-python-sdk-core-v3
pip3 install aliyun-python-sdk-alidns
```

### 脚本
```python
# coding:utf-8
from aliyunsdkcore.client import AcsClient
from aliyunsdkcore.acs_exception.exceptions import ClientException
from aliyunsdkcore.acs_exception.exceptions import ServerException
#from hwx_function import *
from aliyunsdkalidns.request.v20150109.DescribeSubDomainRecordsRequest import DescribeSubDomainRecordsRequest
from aliyunsdkalidns.request.v20150109.DescribeDomainRecordsRequest import DescribeDomainRecordsRequest
from aliyunsdkalidns.request.v20150109.AddDomainRecordRequest import AddDomainRecordRequest
from aliyunsdkalidns.request.v20150109.UpdateDomainRecordRequest import UpdateDomainRecordRequest
import requests
from urllib.request import urlopen
import json

import os
import time
import sqlite3

def Sql_check(ip,TF):
    global old_ip
    # 创建与数据库的连接
    conn = sqlite3.connect('local.db')
    #还可以在内存中创建数据库，只要输入特殊参数值:memory:即可，该数据库只存在于内存中
    #conn = sqlite3.connect(':memory:')
    #创建一个游标 cursor对象，该对象的.execute()方法可以执行sql命令，让我们能够进行数据操作。
    cur = conn.cursor()
    cur.execute('SELECT count(*) FROM sqlite_master WHERE type="table" AND name = "localnetwork"')
    check_table = cur.fetchall()[0][0]
    #print(check_table,type(check_table))
    if check_table == 0:
        # 建表的sql语句
        sql_text_1 = '''CREATE TABLE localnetwork
                    (local_ip TEXT,
                     addr TEXT,
                     num NUMBER);'''
        # 执行sql语句
        cur.execute(sql_text_1)
        # 插入单条数据
        sql_text_2 = "INSERT INTO localnetwork VALUES('k40ip', '127.0.0.1', 0)"
        cur.execute(sql_text_2)
        #对数据库做改动后（比如建表、插数等），都需要手动提交改动，否则无法将数据保存到数据库
        # 提交改动的方法
        conn.commit()

# 查询
    sql_text_3 = "SELECT * FROM localnetwork WHERE local_ip='k40ip'"
    cur.execute(sql_text_3)
    # 获取查询结果
    old_ip = cur.fetchall()[0][1].strip()

if ip != old_ip and TF == 1:
        #update 表名 set 列表名 = 新值 where 列表名 = 某值
        sql_text_update = "update localnetwork set addr='{ip}' where local_ip='k40ip'".format(ip=ip)
        print(sql_text_update)
        cur.execute(sql_text_update)
        conn.commit()

# 关闭游标
    cur.close()
    # 关闭连接
    conn.close()

##修改为真实凭证和地区
accessUser = "testhost.localnetwork.cn@126000000111111.onaliyun.com"
accessKeyId = "BBBBBTAIYxtZAAAAAA8R5888"
accessSecret = "3VABCDOIAywOZaaaAAAaaaAAA5JFGb"
client = AcsClient(accessKeyId, accessSecret, 'cn-hangzhou')

##域名解析记录操作
##域名解析记录不存在时，就新增解析记录，如果已经存在，则修改解析记录；所以这里还需要用到查询子域名解析记录的API；

#子域名解析记录查询
def Describe_SubDomain_Records(client,record_type,subdomain):
    request = DescribeSubDomainRecordsRequest()
    request.set_accept_format('json')

request.set_Type(record_type)
    request.set_SubDomain(subdomain)

response = client.do_action_with_exception(request)
    response = str(response, encoding='utf-8')
    relsult = json.loads(response)
    return relsult

#以下是函数调用以及说明
#des_relsult = Describe_SubDomain_Records(client,"A","testhost.localnetwork.cn")
#des_relsult["TotalCount"]：解析记录的数量，0表示解析记录不存在，1表示有一条解析记录
#des_relsult["DomainRecords"]["Record"][0]["RecordId"]：当des_relsult["TotalCount"]为1时，会返回这个RecordId，后续的修改域名解析记录中需要用到

#新增域名解析记录
def add_record(client,priority,ttl,record_type,value,rr,domainname):
    request = AddDomainRecordRequest()
    request.set_accept_format('json')

request.set_Priority(priority)
    request.set_TTL(ttl)
    request.set_Value(value)
    request.set_Type(record_type)
    request.set_RR(rr)
    request.set_DomainName(domainname)

response = client.do_action_with_exception(request)
    response = str(response, encoding='utf-8')
    relsult = json.loads(response)
    return relsult

#函数调用
#add_relsult = add_record(client,"5","600","A",ip,"testhost.localnetwork.cn")
#record_id = add_relsult["RecordId"]#同样会返回一个RecordId，修改的时候也可以直接调用

#更新域名解析记录
def update_record(client,priority,ttl,record_type,value,rr,record_id):
    request = UpdateDomainRecordRequest()
    request.set_accept_format('json')
    request.set_Priority(priority)
    request.set_TTL(ttl)
    request.set_Value(value)
    request.set_Type(record_type)
    request.set_RR(rr)
    request.set_RecordId(record_id)

response = client.do_action_with_exception(request)
    response = str(response, encoding='utf-8')
    return response

#函数调用
#record_id = des_relsult["DomainRecords"]["Record"][0]["RecordId"]
#update_record(client,"5","600","A",ip,"sz",record_id)

if __name__ == '__main__':
    up_ip = 0
    ip_add = 0
    while ip_add == 0:
        
        p=os.popen("/sbin/ip addr | grep wlan0 | grep 'inet' | awk '{print $2}' | awk -F/ '{print $1}'") 
        time.sleep(3)
        x=p.read()
        ip = str(x).strip()
        if ip != "":
            ip_add = ip_add + 1
        else:
            print("local ip the None")
            os._exit(0)
    #print(x, old_ip) 
    p.close()
    #
    Sql_check(ip,0)
 
    print("本次",ip," ","历史",old_ip) #Sql_check(ip)
    if ip == old_ip:
        print("本地ip未变")
        os._exit(0)
    elif ip == None:
        print("ip None")
        os._exit(0)
    else:
        up_ip = 1  #pass
    des_relsult = Describe_SubDomain_Records(client,"A","testhost.localnetwork.cn")

#print(des_relsult)
    #{'TotalCount': 0, 'RequestId': '00D58888-888A-8888-B53B-5E888888888E', 'PageSize': 20, 'DomainRecords': {'Record': []}, 'PageNumber': 1}
    #{'TotalCount': 1, 'RequestId': '00D58888-888A-8888-B53B-5E888888888E', 'PageSize': 20, 'DomainRecords': {'Record': [{'RR': 'testhost', 'Line': 'default', 'Status': 'ENABLE', 'Locked': False, 'Type': 'A', 'DomainName': 'localnetwork.cn', 'Value': '10.31.14.56', 'RecordId': '8887261888666688866', 'TTL': 600, 'Weight': 1}]}, 'PageNumber': 1}

#print(des_relsult["TotalCount"])
    if des_relsult["TotalCount"] == 0:
        # 0没有查到  #if des_relsult["PageNumber"] == 0:
        pass
        add_relsult = add_record(client,"5","600","A",ip,"testhost","localnetwork.cn")
        record_id = add_relsult["RecordId"]
    else:
        print("云上ip:",des_relsult["DomainRecords"]["Record"][0]["Value"])
        record_id = des_relsult["DomainRecords"]["Record"][0]["RecordId"]
        if ip != des_relsult["DomainRecords"]["Record"][0]["Value"]:
            #print("判断地址不相等")
            response = update_record(client,"5","600","A",ip,"testhost",record_id)
            #print(type(response), str(response))
            print("云上IP更新为{}".format(ip))
        else:
            print("云上IP没变{}".format(ip))

if up_ip == 1:
        Sql_check(ip,1)
        print("update true")
```