regex carry look behind ip adress

Question

Is there a regex, which will read and return the ip address in proper format in this text? Note it's backward, so the regex would have to step through the code backwards then replace '|' with '.'

It's been driving me crazy... and I'd appreciate your help ;)

Excerpt From Code:

4.3/d/c/b.a",10:"0://8.7/1/1.f",z:"0://8.7/1/y.x",w:"0://6.5.4.3/i/v/u.t",s:"r",q:p,o:n,9:\'0\',m:[{2:"l",k:"0://8.7/1/1.f"},{2:"j",h:{e:\'0://6.5.4.3/d/c/b.a\',\'9\':\'0\'}},{2:"g"}]});',36,40,'|type|187|20|207|31|com|hystorystingbulk|

Desired Return:

31.207.20.187

Thanks!

Edit: I have bits and pieces, but I can't put it together to get me the desired outcome

(?<=/|^) -- a positive lookbehind

\b\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}\b -- this will get you the ip in a given file/text

\b\d{1,3}\|\d{1,3}\|\d{1,3}\|\d{1,3}\b --this returns the ip (but backwards. remember I wanted it flipped) and separated by '|' instead of '.'

Someone asked....I'm using Python and testing using http://www.regexplanet.com/advanced/python/index.html THX

Could you post the code you already tried? This is not a 'we will write your code for free'-site. — Martin Tournoij, Feb 16 '14 at 01:11
Also, it might be a good idea to specify which regex engine (or at least, which language) you're using. There are so many differences between PCRE and POXIX extended regexes, for example. — jpaugh, Feb 16 '14 at 01:17
There's nothing *simple* about regexes, that's for sure: why not download python and use it locally? Or look for an online full-blown interpreter? Why must you use this site in particular? — jpaugh, Feb 16 '14 at 01:43

jpaugh · Answer 1 · 2014-02-16T01:38:46.683

1

Probably the best way is to store each number individually into a group, then format and join the groups together later.

Some such:

/(\d+)\|(\d+)\|(\d+)|(\d+)/

That creates 5 different match groups, one for each set of parents ( ) and one around the whole match. But this ain't Perl! Now, in Python that would have to be more like

match("(\\d+)\\|(\\d+)\\|(\\d+)|(\\d+)", ..)

Then, use group to grab out the individual matches and put them together in the right order:

group(...) "." group(...) "." group(...) "." group(...)

Tada!

Disclaimer: This is not really Pythonic syntax, but should give you an idea.

edited Feb 16 '14 at 01:38

answered Feb 16 '14 at 01:15

jpaugh

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Thanks, but that's not an option I have :( – user2957951 Feb 16 '14 at 01:25
I don't think there really is another option. What are you using? `sed`?? – jpaugh Feb 16 '14 at 01:29
It's certainly possibly in Python, with match and groups. – jpaugh Feb 16 '14 at 01:29
I just need to piece those (see my edits together) :( – user2957951 Feb 16 '14 at 01:32
Here's an answer from today that uses match groups, in Python: http://stackoverflow.com/a/21805543/712526 – jpaugh Feb 16 '14 at 01:32
Thanks jpaugh....but no can do :( I need simple expression like those mentioned in my edits. – user2957951 Feb 16 '14 at 01:35
Well... no *can* do, then! :-) – jpaugh Feb 16 '14 at 01:39
Unles you find some way to wrap it in a lambda. Syntactically, they *are* expressions. – jpaugh Feb 16 '14 at 01:39

score 0 · Answer 2 · answered Feb 16 '14 at 02:22

import re
expression = re.compile("(\d{1,3})\|(\d{1,3})\|(\d{1,3})\|(\d{1,3})")
text = """4.3/d/c/b.a",10:"0://8.7/1/1.f",z:"0://8.7/1/y.x",w:"0://6.5.4.3/i/v/u.t",s:"r",q:p,o:n,9:\'0\',m:[{2:"l",k:"0://8.7/1/1.f"},{2:"j",h:{e:\'0://6.5.4.3/d/c/b.a\',\'9\':\'0\'}},{2:"g"}]});',36,40,'|type|187|20|207|31|com|hystorystingbulk|"""

matches = expression.findall(text)

IPs = ['.'.join(reversed(match)) for match in matches]

>>> print(IPs)
['31.207.20.187']

regex carry look behind ip adress

2 Answers2