You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
60 lines
1.7 KiB
60 lines
1.7 KiB
4 months ago
|
# Copyright 2014 Google Inc.
|
||
|
|
#
|
||
|
|
# Use of this source code is governed by a BSD-style license that can be
|
||
|
|
# found in the LICENSE file.
|
||
|
|
|
||
|
|
|
||
|
|
"""Miscellaneous utilities."""
|
||
|
|
|
||
|
|
|
||
|
|
import re
|
||
|
|
|
||
|
|
|
||
|
|
class ReSearch(object):
|
||
|
|
"""A collection of static methods for regexing things."""
|
||
|
|
|
||
|
|
@staticmethod
|
||
|
|
def search_within_stream(input_stream, pattern, default=None):
|
||
|
|
"""Search for regular expression in a file-like object.
|
||
|
|
|
||
|
|
Opens a file for reading and searches line by line for a match to
|
||
|
|
the regex and returns the parenthesized group named return for the
|
||
|
|
first match. Does not search across newlines.
|
||
|
|
|
||
|
|
For example:
|
||
|
|
pattern = '^root(:[^:]*){4}:(?P<return>[^:]*)'
|
||
|
|
with open('/etc/passwd', 'r') as stream:
|
||
|
|
return search_within_file(stream, pattern)
|
||
|
|
should return root's home directory (/root on my system).
|
||
|
|
|
||
|
|
Args:
|
||
|
|
input_stream: file-like object to be read
|
||
|
|
pattern: (string) to be passed to re.compile
|
||
|
|
default: what to return if no match
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
A string or whatever default is
|
||
|
|
"""
|
||
|
|
pattern_object = re.compile(pattern)
|
||
|
|
for line in input_stream:
|
||
|
|
match = pattern_object.search(line)
|
||
|
|
if match:
|
||
|
|
return match.group('return')
|
||
|
|
return default
|
||
|
|
|
||
|
|
@staticmethod
|
||
|
|
def search_within_string(input_string, pattern, default=None):
|
||
|
|
"""Search for regular expression in a string.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
input_string: (string) to be searched
|
||
|
|
pattern: (string) to be passed to re.compile
|
||
|
|
default: what to return if no match
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
A string or whatever default is
|
||
|
|
"""
|
||
|
|
match = re.search(pattern, input_string)
|
||
|
|
return match.group('return') if match else default
|
||
|
|
|