Question

Basically, I have a file like this:

Url/Host:   www.example.com
Login:     user
Password:   password
Data_I_Dont_Need:    something_else

How can I use RegEx to separate the details to place them into variables?

Sorry if this is a terrible question, I can just never grasp RegEx. So another question would be, can you provide the RegEx, but kind of explain what each part of it is for?

Answer 1

You should put the entries in a dictionary, not in so many separate variables — clearly, the keys you’re using need NOT be acceptable as variable names (that slash in ‘Url/Host’ would be a killer!-), but they’ll be just fine as string keys into a dictionary.

import re

there = re.compile(r'''(?x)      # verbose flag: allows comments & whitespace
                       ^         # anchor to the start
                       ([^:]+)   # group with 1+ non-colons, the key
                       :\s*      # colon, then arbitrary whitespace
                       (.*)      # group everything that follows
                       $         # anchor to the end
                    ''')

and then

 configdict = {}
 for aline in open('thefile.txt'):
   mo = there.match(aline)
   if not mo:
     print("Skipping invalid line %r" % aline)
     continue
   k, v = mo.groups()
   configdict[k] = v

the possibility of making RE patterns “verbose” (by starting them with (?x) or using re.VERBOSE as the second argument to re.compile) is very useful to allow you to clarify your REs with comments and nicely-aligning whitespace. I think it’s sadly underused;-).