正则表达式python条形字符

Question

I have a text file:

z.server(y.host=>["x.012345","x.054321","x.045455"], :stop => 10)
z.server(y.host=>["x.067891","x.043215","x.045195"], :stop => 10)
z.server(y.host=>["x.012355","x.075321","x.045855"], :stop => 10)

I have a script which I want to extract the following data:

y.host 012345 012345 012345
y.host 067891 043215 045195
y.host 012355 075321 075321

When I run my python script I get:

y.host 012345","x.054321","x.045455
y.host 067891","x.043215","x.045195
y.host 012355","x.075321","x.045855

What am I missing? Appreciate any help.

Here's my script:

#!/usr/bin/python

import re,sys

f = "test.txt"

rgxxid = re.compile('(^z\.\w+\((\w+\.\w+)=>\["x\.(\d+.*)"\]).\s+:\w+\s+=>\s\d+\)')

for l in open(f,'r').readlines():

   lm = re.match(rgxxid,l)

   if lm:

      hlm = lm.group(2)
      xid = lm.group(3)

      print hlm, xid

   else:
      sys.stderr.write("No XID match. "+l+"\n")

Answer 1

In brief, here is the problem with your current regex:

["x\.(\d+.*)"\]
         ^^^

The pattern \\d+.* says to match one or more digits followed by anything up until the last quote. What you are seeing in your output confirms this:

y.host 012345","x.054321","x.045455

The capture group has consumed everything until the end of the numbers list. Instead, try using the following pattern:

^z\.\w+\((\w+\.\w+)=>\["x\.(\d+)","x\.(\d+)","x\.(\d+)"\],\s+:\w+\s+=>\s\d+\)

Here, I provide three explicit capture groups for each of the three numners. Here is a demo for the regex:

Demo

Your updated script should look something like this:

for l in open(f,'r').readlines():

lm = re.match(rgxxid,l)

if lm:

  term1 = lm.group(1)
  term2 = lm.group(2)
  term3 = lm.group(3)
  term4 = lm.group(4)

  print term1, term2, term3, term4

else:
  sys.stderr.write("No XID match. "+l+"\n")

Answer 2

You might find it easier to use pyparsing . It definitely makes it simpler to capture the grammar of the lines that you have offered as examples.

Notice:

• What appear to be server names are defined as mixtures of alphabetic characters and periods. This could be expanded.
• The list could contain and retrieve an indefinite number of constants.

.

import pyparsing as pp

server = pp.Word(pp.alphas+'.')
item = pp.Suppress('"x.') + pp.Word(pp.nums) + pp.Suppress('"')
one_line = server.suppress() + pp.Suppress('(') + server + pp.Suppress('=>[') + item + pp.OneOrMore(pp.Suppress(',') + item)

lines = '''\
z.server(y.host=>["x.012345","x.054321","x.045455"], :stop => 10)
z.server(y.host=>["x.067891","x.043215","x.045195"], :stop => 10)
z.server(y.host=>["x.012355","x.075321","x.045855"], :stop => 10)'''

for line in lines.split('\n'):
    print (line)
    parsed = one_line.parseString(line)
    print ('\t', parsed[:5])

Output:

z.server(y.host=>["x.012345","x.054321","x.045455"], :stop => 10)
     ['y.host', '012345', '054321', '045455']
z.server(y.host=>["x.067891","x.043215","x.045195"], :stop => 10)
     ['y.host', '067891', '043215', '045195']
z.server(y.host=>["x.012355","x.075321","x.045855"], :stop => 10)
     ['y.host', '012355', '075321', '045855']