Filtering os.walk() dirs and files
I'm looking for a way to include/exclude files patterns and exclude directories from a os.walk()
call.
Here's what I'm doing by now:
import fnmatch
import os
includes = ['*.doc', '*.odt']
excludes = ['/home/paulo-freitas/Documents']
def _filter(paths):
for path in paths:
if os.path.isdir(path) and not path in excludes:
yield path
for pattern in (includes + excludes):
if not os.path.isdir(path) and fnmatch.fnmatch(path, pattern):
yield path
for root, dirs, files in os.walk('/home/paulo-freitas'):
dirs[:] = _filter(map(lambda d: os.path.join(root, d), dirs))
files[:] = _filter(map(lambda f: os.path.join(root, f), files))
for filename in files:
filename = os.path.join(root, filename)
print(filename)
Is there a better way to do this? How?
This solution uses fnmatch.translate
to convert glob patterns to regular expressions (it assumes the includes only is used for files):
import fnmatch
import os
import os.path
import re
includes = ['*.doc', '*.odt'] # for files only
excludes = ['/home/paulo-freitas/Documents'] # for dirs and files
# transform glob patterns to regular expressions
includes = r'|'.join([fnmatch.translate(x) for x in includes])
excludes = r'|'.join([fnmatch.translate(x) for x in excludes]) or r'$.'
for root, dirs, files in os.walk('/home/paulo-freitas'):
# exclude dirs
dirs[:] = [os.path.join(root, d) for d in dirs]
dirs[:] = [d for d in dirs if not re.match(excludes, d)]
# exclude/include files
files = [os.path.join(root, f) for f in files]
files = [f for f in files if not re.match(excludes, f)]
files = [f for f in files if re.match(includes, f)]
for fname in files:
print fname
From docs.python.org:
os.walk(top[, topdown=True[, onerror=None[, followlinks=False]]])
When topdown is True, the caller can modify the dirnames list in-place … this can be used to prune the search …
for root, dirs, files in os.walk('/home/paulo-freitas', topdown=True):
# excludes can be done with fnmatch.filter and complementary set,
# but it's more annoying to read.
dirs[:] = [d for d in dirs if d not in excludes]
for pat in includes:
for f in fnmatch.filter(files, pat):
print os.path.join(root, f)
I should point out that the above code assumes excludes
is a pattern, not a full path. You would need to adjust the list comprehension to filter if os.path.join(root, d) not in excludes
to match the OP case.
why fnmatch?
import os
excludes=....
for ROOT,DIR,FILES in os.walk("/path"):
for file in FILES:
if file.endswith(('doc','odt')):
print file
for directory in DIR:
if not directory in excludes :
print directory
not exhaustively tested