Current File : //usr/lib/python2.7/site-packages/salt/utils/itertools.py
# -*- coding: utf-8 -*-
'''
Helpful generators and other tools
'''
# Import python libs
from __future__ import absolute_import, unicode_literals
import fnmatch
import re
# Import Salt libs
import salt.utils.files
def split(orig, sep=None):
'''
Generator function for iterating through large strings, particularly useful
as a replacement for str.splitlines().
See http://stackoverflow.com/a/3865367
'''
exp = re.compile(r'\s+' if sep is None else re.escape(sep))
pos = 0
length = len(orig)
while True:
match = exp.search(orig, pos)
if not match:
if pos < length or sep is not None:
val = orig[pos:]
if val:
# Only yield a value if the slice was not an empty string,
# because if it is then we've reached the end. This keeps
# us from yielding an extra blank value at the end.
yield val
break
if pos < match.start() or sep is not None:
yield orig[pos:match.start()]
pos = match.end()
def read_file(fh_, chunk_size=1048576):
'''
Generator that reads chunk_size bytes at a time from a file/filehandle and
yields it.
'''
try:
if chunk_size != int(chunk_size):
raise ValueError
except ValueError:
raise ValueError('chunk_size must be an integer')
try:
while True:
try:
chunk = fh_.read(chunk_size)
except AttributeError:
# Open the file and re-attempt the read
fh_ = salt.utils.files.fopen(fh_, 'rb') # pylint: disable=W8470
chunk = fh_.read(chunk_size)
if not chunk:
break
yield chunk
finally:
try:
fh_.close()
except AttributeError:
pass
def fnmatch_multiple(candidates, pattern):
'''
Convenience function which runs fnmatch.fnmatch() on each element of passed
iterable. The first matching candidate is returned, or None if there is no
matching candidate.
'''
# Make sure that candidates is iterable to avoid a TypeError when we try to
# iterate over its items.
try:
candidates_iter = iter(candidates)
except TypeError:
return None
for candidate in candidates_iter:
try:
if fnmatch.fnmatch(candidate, pattern):
return candidate
except TypeError:
pass
return None
Mini Shell