Cómo resolver DNS en Python?

Question

Tengo un script DNS, que permiten a los usuarios nombres DNS determinación de nombres de sitios web a escribir en un símbolo del sistema de Windows.

He mirado a través de varias guías sobre la resolución DNS, pero mi guión no puedo todavía parecen resolver los nombres (www.google.com) o (google.com) a la dirección IP.

El script genera un error de

Traceback (most recent call last):
  File "C:\python\main_menu.py", line 37, in ?
    execfile('C:\python\showdns.py')
  File "C:\python\showdns.py", line 3, in ?
    x = input ("\nPlease enter a domain name that you wish to translate: ")
  File "<string>", line 0, in ?
NameError: name 'google' is not defined

El código:

import socket

x = input ("\nPlease enter a domain name that you wish to translate: ")

print ("\n\nThe IP Address of the Domain Name is: "+socket.gethostbyname_ex(x))

x = raw_input("\nSelect enter to proceed back to Main Menu\n")
if x == '1': 
execfile('C:\python\main_menu.py')

Por favor, dar consejos sobre los códigos. Gracias!

Answer 1

input () es la función de error utilizar aquí. En realidad, se evalúa la cadena que el usuario ha introducido.

gethostbyname_ex vuelve algo más que una cadena. Por lo que su sentencia print también habría fracasado.

En el caso de este código debería funcionar:

import socket

x = raw_input ("\nPlease enter a domain name that you wish to translate: ")  

data = socket.gethostbyname_ex(x)
print ("\n\nThe IP Address of the Domain Name is: "+repr(data))  

x = raw_input("\nSelect enter to proceed back to Main Menu\n")  
if x == '1':   
    execfile('C:\python\main_menu.py')  

Answer 2

#!/user/bin/env python
"""
Resolve the DNS/IP address of a given domain
data returned is in the format:
(name, aliaslist, addresslist)
@filename resolveDNS.py
@version 1.01 (python ver 2.7.3)
@author LoanWolffe
"""
import socket

def getIP(d):
    """
    This method returns the first IP address string
    that responds as the given domain name
    """
    try:
        data = socket.gethostbyname(d)
        ip = repr(data)
        return ip
    except Exception:
        # fail gracefully!
        return False
#
def getIPx(d):
    """
    This method returns an array containing
    one or more IP address strings that respond
    as the given domain name
    """
    try:
        data = socket.gethostbyname_ex(d)
        ipx = repr(data[2])
        return ipx
    except Exception:
        # fail gracefully!
        return False
#
def getHost(ip):
    """
    This method returns the 'True Host' name for a
    given IP address
    """
    try:
        data = socket.gethostbyaddr(ip)
        host = repr(data[0])
        return host
    except Exception:
        # fail gracefully
        return False
#
def getAlias(d):
    """
    This method returns an array containing
    a list of aliases for the given domain
    """
    try:
        data = socket.gethostbyname_ex(d)
        alias = repr(data[1])
        #print repr(data)
        return alias
    except Exception:
        # fail gracefully
        return False
#

# test it

x = raw_input("Domain name or IP address? > ")


a = getIP(x)
b = getIPx(x)
c = getHost(x)
d = getAlias(x)

print " IP ", a
print " IPx ", b
print " Host ", c
print " Alias ", d

Answer 3

Uso raw_input en lugar de input.