python實現域名解析和歸屬地查詢

1. 前言
   工做中有時要查詢域名解析和獲取域名相關IP歸屬地信息
2. 安裝依賴
   python2:
   pip install dnspython
   python3:
   python3 -m pip install -i https://pypi.douban.com/simple/ dnspython3
3. 腳本內容
   

   #!/usr/bin/env python
   #coding:utf-8
    
   import dns.resolver
   import urllib
   import chardet
   import sys
   import re
    
   ip_list = []
   query_domain = sys.argv[1]
   #query_domain = raw_input('Please input a domain: ')
    
   # 先查詢是否有CNAME，若是有則經過CNAME獲取到A記錄；若是沒有直接獲取A記錄，而後返回到一個列表中
   def get_iplist(domain):
       try:
           cn = dns.resolver.query(domain,'CNAME')
           for i in cn.response.answer:
               for j in i.items:
                   cname_domain = j.to_text() 
           print '========================================'
           print '    CNAME  --->', cname_domain
           print '========================================'
       except:
           pass
       else:
           A = dns.resolver.query(cname_domain,'A')
           for i in A.response.answer:
               for j in i.items:
                   try:
                       ip_list.append(j.address)
                   except:
                       get_iplist(str(j))
            
       try:
           A = dns.resolver.query(domain,'A')
           for i in A.response.answer:
               for j in i.items:
                   ip_list.append(j.address)
       except:
           pass
       return ip_list
    
   # 經過調用ip138.com來獲取IP歸屬地信息
   def get_ipbelong(domain_ip):
       url = 'http://ip138.com/ips138.asp?ip=%s&action=2' % domain_ip
       content = urllib.urlopen(url).read()
       typeEncode = sys.getfilesystemencoding()
       infoencode = chardet.detect(content).get('encoding','utf-8')
       html = content.decode(infoencode,'ignore').encode(typeEncode)
       ip = re.findall(r'\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}',html)
       result = re.findall(r'(<li>.*?</li>)',html)
       belong = result[0][14:-5]
       print '%-*s--->%*s' % (18,ip[0],20,belong)
    
    
   if __name__ == '__main__':
       get_iplist(query_domain)
       for ip in ip_list:
           get_ipbelong(ip)

4. 使用python domain2ip.py www.baidu.com