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Python Regular Expression Lookahead overshooting pattern

I am trying to pull the data contained in FTP LIST.

I am using regex in Python 2.7.

test = "-rw-r--r--   1 owner    group        75148624 Jan  6  2015 somename.csv-rw-r--r--   1 owner    group       223259072 Feb 26  2015 somename.csv-rw-r--r--   1 owner    group         4041411 Jun  5  2015 somename-adjusted.csv-rw-r--r--   1 owner    group         2879228 May 13  2015 somename.csv-rw-r--r--   1 owner    group        11832668 Feb 13  2015 somename.csv-rw-r--r--   1 owner    group         1510522 Feb 19  2015 somename.csv-rw-r--r--   1 owner    group         2826664 Feb 25  2015 somename.csv-rw-r--r--   1 owner    group          582985 Feb 26  2015 somename.csv-rw-r--r--   1 owner    group          212427 Feb 26  2015 somename.csv-rw-r--r--   1 owner    group         3015592 Feb 27  2015 somename.csv-rw-r--r--   1 owner    group          103576 Feb 27  2015    somename-corrected.csv"

(now without formatting the code so you can see it without scrolling)

test = "-rw-r - r-- 1 group of owners 75148624 January 6, 2015 somename.csv-rw-r - r-- 1 group of owners 223259072 February 26, 2015 somename.csv-rw-r-- r - 1 group of owners 4041411 June 5, 2015 somename-adjust.csv-rw-r - r-- 1 group of owners 2879228 May 13, 2015 somename.csv-rw-r - r-- 1 group of owners 11832668 February 13 2015 somename.csv-rw-r - r-- 1 group of owners 1510522 February 19, 2015 somename.csv-rw-r - r-- 1 group of owners 2826664 February 25, 2015 somename.csv-rw-r - r-- 1 group of owners 582985 February 26, 2015 somename.csv-rw-r - r-- 1 group of owners 212427 February 26, 2015 somename.csv-rw-r - r-- 1 group of owners 3015592 February 27 2015 somename.csv-rw -r - r-- 1 group of owners 10 3576 February 27, 2015 somename-corrected.csv "

I have tried various incarnations of the following

from re import compile
ftp_list_re = compile('(?P<permissions>[d-][rwx-]{9})[\s]{1,20}'
                      '(?P<links>[0-9]{1,8})[\s]{1,20}'
                      '(?P<owner>[0-9A-Za-z_-]{1,16})[\s]{1,20}'
                      '(?P<group>[0-9A-Za-z_-]{1,16})[\s]{1,20}'
                      '(?P<size>[0-9]{1,16})[\s]{1,20}'
                      '(?P<month>[A-Za-z]{0,3})[\s]{1,20}'
                      '(?P<date>[0-9]{1,2})[\s]{1,20}'
                      '(?P<timeyear>[0-9:]{4,5})[\s]{1,20}'
                      '(?P<filename>[\s\w\.\-]+)(?=[drwx\-]{10})')


'(?P<filename>.+)(?=[drwx\-]{10})')

'(?P<filename>.+(?=[drwx\-]{10}))')

,

'(?P<filename>[\s\w\.\-]+(?=[drwx\-]{10}|$))')

,

ftp_list_re.findall(test)

[('-rw-r--r--',
  '1',
  'owner',
  'group',
  '75148624',
  'Jan',
  '6',
  '2015',
  'somename.csv-rw-r--r--   1 owner    group       223259072 Feb 26  2015     somename.csv-rw-r--r--   1 owner    group         4041411 Jun  5  2015 somename-adjusted.csv-rw-r--r--   1 owner    group         2879228 May 13  2015 somename.csv-rw-r--r--   1 owner    group        11832668 Feb 13  2015 somename.csv-rw-r--r--   1 owner    group         1510522 Feb 19  2015 somename.csv-rw-r--r--   1 owner    group         2826664 Feb 25  2015 somename.csv-rw-r--r--   1 owner    group          582985 Feb 26  2015 somename.csv-rw-r--r--   1 owner    group          212427 Feb 26  2015 somename.csv-rw-r--r--   1 owner    group         3015592 Feb 27  2015 somename.csv')]

?

+4
4

, . :

(?P<permissions>[d-][rwx-]{9})\s{1,20}(?P<links>\d{1,8})\s{1,20}(?P<owner>[\w-]{1,16})\s{1,20}(?P<group>[\w-]{1,16})\s{1,20}(?P<size>\d{1,16})\s{1,20}(?P<month>[A-Za-z]{0,3})\s{1,20}(?P<date>\d{1,2})\s{1,20}(?P<timeyear>[\d:]{4,5})\s{1,20}(?P<filename>[\s\w.-]+?)(?=[drwx-]{10}|$)

compile:

from re import compile

ftp_list_re = compile('(?P<permissions>[d-][rwx-]{9})\s{1,20}'
   '(?P<links>\d{1,8})\s{1,20}'
   '(?P<owner>[\w-]{1,16})\s{1,20}'
   '(?P<group>[\w-]{1,16})\s{1,20}'
   '(?P<size>\d{1,16})\s{1,20}'
   '(?P<month>[A-Za-z]{0,3})\s{1,20}'
   '(?P<date>\d{1,2})\s{1,20}'
   '(?P<timeyear>[\d:]{4,5})\s{1,20}'
   '(?P<filename>[\s\w.-]+?)(?=[drwx-]{10}|$)')

- RegEx

:

import re
p = re.compile(ur'(?P<permissions>[d-][rwx-]{9})\s{1,20}(?P<links>\d{1,8})\s{1,20}(?P<owner>[\w-]{1,16})\s{1,20}(?P<group>[\w-]{1,16})\s{1,20}(?P<size>[0-9]{1,16})\s{1,20}(?P<month>[A-Za-z]{0,3})\s{1,20}(?P<date>[0-9]{1,2})\s{1,20}(?P<timeyear>[\d:]{4,5})\s{1,20}(?P<filename>[\s\w.-]+?)(?=[drwx-]{10}|$)')
test_str = u"-rw-r--r--   1 owner    group        75148624 Jan  6  2015 somename.csv-rw-r--r--   1 owner    group       223259072 Feb 26  2015 somename.csv-rw-r--r--   1 owner    group         4041411 Jun  5  2015 somename-adjusted.csv-rw-r--r--   1 owner    group         2879228 May 13  2015 somename.csv-rw-r--r--   1 owner    group        11832668 Feb 13  2015 somename.csv-rw-r--r--   1 owner    group         1510522 Feb 19  2015 somename.csv-rw-r--r--   1 owner    group         2826664 Feb 25  2015 somename.csv-rw-r--r--   1 owner    group          582985 Feb 26  2015 somename.csv-rw-r--r--   1 owner    group          212427 Feb 26  2015 somename.csv-rw-r--r--   1 owner    group         3015592 Feb 27  2015 somename.csv-rw-r--r--   1 owner    group          103576 Feb 27  2015 somename-corrected.csv"

re.findall(p, test_str)
+2

"", , "" .

[\s\w\.\-]+

, , . , ( , ), , , (, , ).

? (*?, +?,?? ..) "" "". "+" " " " ".

, + +? .

, , , .

EDIT:

. , INSISTS . , , ( , , ). ,

ftp_list_re = compile('(?P<permissions>[d-][rwx-]{9})[\s]{1,20}'
                      '(?P<links>[0-9]{1,8})[\s]{1,20}'
                      '(?P<owner>[0-9A-Za-z_-]{1,16})[\s]{1,20}'
                      '(?P<group>[0-9A-Za-z_-]{1,16})[\s]{1,20}'
                      '(?P<size>[0-9]{1,16})[\s]{1,20}'
                      '(?P<month>[A-Za-z]{0,3})[\s]{1,20}'
                      '(?P<date>[0-9]{1,2})[\s]{1,20}'
                      '(?P<timeyear>[0-9:]{4,5})[\s]{1,20}'
                      '(?P<filename>[\s\w\.\-]+?)(?=(?:(?:[drwx\-]{10})|$))')

, ( + ), , lookahead - , . "?" - ( ).

+2

​​ , . . :

(?P<permissions>[d-][rwx-]{9})[\s]{1,20}
                      (?P<links>[0-9]{1,8})[\s]{1,20}
                      (?P<owner>[0-9A-Za-z_-]{1,16})[\s]{1,20}
                      (?P<group>[0-9A-Za-z_-]{1,16})[\s]{1,20}
                      (?P<size>[0-9]{1,16})[\s]{1,20}
                      (?P<month>[A-Za-z]{0,3})[\s]{1,20}
                      (?P<date>[0-9]{1,2})[\s]{1,20}
                      (?P<timeyear>[0-9:]{4,5})[\s]{1,20}
                      (?P<filename>[\w\-]+.\w+)

:

0

PyPi regex , , , :

import regex

fields = ('permissions', 'links', 'owner', 'group', 'size', 'month', 'day', 'year', 'filename')
p = regex.compile(r'(?=[d-](?:[r-][w-][x-]){3})', regex.V1)
res = [dict(zip(fields, x.split(None, 9))) for x in p.split(test)[1:]]
0

Source: https://habr.com/ru/post/1622573/

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