Python - checking for an ip address (and nothing after it)

Question

I'm trying to create a Python (2.7) function that will take a string and return true if its input is an ip address, possibly with a slash in the end, but false otherwise. It needs to return a false value if the string is not just an ip address, but an ip address followed by some sort of path. It doesn't matter if the address is a valid IP or not (999.999.999.999 can be considered an ip address for that matter).

eg: "124.131.141.248" - true "124.131.141.248/" - true "124.131.141.248/bla" - false "hello world" - false

I've tried searching for a solution but most solutions include just checking for a valid IP address, disregarding my other needs.

Any help would be appreciated.

Thanks,

Or the new [`ipaddress` module](https://docs.python.org/3/library/ipaddress.html) might help. — languitar, Apr 03 '17 at 08:43
Please include a [Minimal, Complete, and Verifiable example](http://stackoverflow.com/help/mcve) — Glrs, Apr 03 '17 at 08:49

lch · Answer 1 · 2017-04-03T11:19:53.753

0

That seems to be working:

import re
def valid_ip(ip):
    if re.match(r'(\d+\.?){4}\\?$', ip):
        return True
    else:
        return False

edited Apr 03 '17 at 11:19

answered Apr 03 '17 at 08:46

lch

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Why the `^` at the end of the regular expression? – Matthias Apr 03 '17 at 09:19
My bad, `$` is right. – lch Apr 03 '17 at 11:20

score 0 · Answer 2 · answered Apr 03 '17 at 08:49

0

Quite easy to solve using a simple regex:

import re
pattern = re.compile("\d{3}\.\d{3}\.\d{3}\.\d{3}(\/)?$")
string1 = "124.131.141.248"
string2 = "124.131.141.248/"
string3 = "124.131.141.248/bla"
string4 = "hello world" 
print(pattern.match(string1)!=None) # true
print(pattern.match(string2)!=None) # true
print(pattern.match(string3)!=None) # false
print(pattern.match(string4)!=None) # false

Here a running example.

answered Apr 03 '17 at 08:49

rakwaht

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Thanks! That seems to work, I should've thought of it myself – Gil Apr 03 '17 at 09:49

Python - checking for an ip address (and nothing after it)

2 Answers2