I am new to python and want to run a code in Python.
Code that I have written is
#!/usr/bin/python
import sys
import re
for line in sys.stdin:
results = re.search('ipAddress=([^&]*])', line)
if len(results.group(1)) != 0:
print results.group(1)
Requirement is finding IP address in a string.String will be something like this
blah....ipAddress=173.110.208.118&deviceId
Output: 173.110.208.118
Please let me know what I am doing wrong..
I think you've got one ] too many there. Try
results = re.search('ipAddress=([^&]*)', line)
Your input looks like URL query string. Don't parse it by regexp, consider to use urlparse.parse_qs or urlparse.parse_qsl (for Python version less than 2.6 use cgi.parse_qs or cgi.parse_qsl respectively). Those functions hide many low level details, for example handling of URL encoded characters.
Example code for urlparse.parse_qs:
>>> from urlparse import parse_qs
>>> query = parse_qs("ipAddress=173.110.208.118&deviceId=Some%20Id")
>>> query["ipAddress"]
['173.110.208.118']
>>> query["deviceId"]
['Some Id']
In urlparse module you can also find functions for extracting query string from a full URL.
awk '/ipAddress=/ {print $2}' FS='ipAddress=|&' < lines.txt. If you learn Python it's important to know about most frequently used modules in the standard library.If you're paranoid about regex being too greedy you can use this one to explicitly match the contents like xxx.xxx.xxx.xxx
>import re
>s = "blah...ipAddress=173.110.208.118&deviceid"
>results = re.search('ipAddress=(\d+\.\d+\.\d+\.\d+)',s)
>results.groups()
('173.110.208.118',)
Any specific reason for not using regex?
No, there's no need of a more complicated tool. If your string has a strongly repeatitive pattern, even regex are not absolutely required:
ch = 'blah....ipAddress=173.110.208.118&deviceId'
print ch.split('=')[1].split('&')[0]
print ch.split('=')[1][0:15]
print ch[-34:].strip('ipAddress=&deviceId')
result
173.110.208.118
173.110.208.118
173.110.208.118
