CasperSecurity
# coding: utf-8
from __future__ import division
import io
import sys
import posixpath
import zipfile
import functools
import itertools
import re
import more_itertools
__metaclass__ = type
def _parents(path):
"""
Given a path with elements separated by
posixpath.sep, generate all parents of that path.
>>> list(_parents('b/d'))
['b']
>>> list(_parents('/b/d/'))
['/b']
>>> list(_parents('b/d/f/'))
['b/d', 'b']
>>> list(_parents('b'))
[]
>>> list(_parents(''))
[]
"""
return itertools.islice(_ancestry(path), 1, None)
def _ancestry(path):
"""
Given a path with elements separated by
posixpath.sep, generate all elements of that path
>>> list(_ancestry('b/d'))
['b/d', 'b']
>>> list(_ancestry('/b/d/'))
['/b/d', '/b']
>>> list(_ancestry('b/d/f/'))
['b/d/f', 'b/d', 'b']
>>> list(_ancestry('b'))
['b']
>>> list(_ancestry(''))
[]
"""
path = path.rstrip(posixpath.sep)
while path and path != posixpath.sep:
yield path
path, tail = posixpath.split(path)
class SanitizedNames:
"""
ZipFile mix-in to ensure names are sanitized.
"""
def namelist(self):
return list(map(self._sanitize, super().namelist()))
@staticmethod
def _sanitize(name):
r"""
Ensure a relative path with posix separators and no dot names.
Modeled after
https://github.com/python/cpython/blob/bcc1be39cb1d04ad9fc0bd1b9193d3972835a57c/Lib/zipfile/__init__.py#L1799-L1813
but provides consistent cross-platform behavior.
>>> san = SanitizedNames._sanitize
>>> san('/foo/bar')
'foo/bar'
>>> san('//foo.txt')
'foo.txt'
>>> san('foo/.././bar.txt')
'foo/bar.txt'
>>> san('foo../.bar.txt')
'foo../.bar.txt'
>>> san('\\foo\\bar.txt')
'foo/bar.txt'
>>> san('D:\\foo.txt')
'D/foo.txt'
>>> san('\\\\server\\share\\file.txt')
'server/share/file.txt'
>>> san('\\\\?\\GLOBALROOT\\Volume3')
'?/GLOBALROOT/Volume3'
>>> san('\\\\.\\PhysicalDrive1\\root')
'PhysicalDrive1/root'
Retain any trailing slash.
>>> san('abc/')
'abc/'
Raises a ValueError if the result is empty.
>>> san('../..')
Traceback (most recent call last):
...
ValueError: Empty filename
"""
def allowed(part):
return part and part not in {'..', '.'}
# Remove the drive letter.
# Don't use ntpath.splitdrive, because that also strips UNC paths
bare = re.sub('^([A-Z]):', r'\1', name, flags=re.IGNORECASE)
clean = bare.replace('\\', '/')
parts = clean.split('/')
joined = '/'.join(filter(allowed, parts))
if not joined:
raise ValueError("Empty filename")
return joined + '/' * name.endswith('/')
class Path:
"""
A pathlib-compatible interface for zip files.
Consider a zip file with this structure::
.
├── a.txt
└── b
├── c.txt
└── d
└── e.txt
>>> data = io.BytesIO()
>>> zf = zipfile.ZipFile(data, 'w')
>>> zf.writestr('a.txt', 'content of a')
>>> zf.writestr('b/c.txt', 'content of c')
>>> zf.writestr('b/d/e.txt', 'content of e')
>>> zf.filename = 'abcde.zip'
Path accepts the zipfile object itself or a filename
>>> root = Path(zf)
From there, several path operations are available.
Directory iteration (including the zip file itself):
>>> a, b = root.iterdir()
>>> a
Path('abcde.zip', 'a.txt')
>>> b
Path('abcde.zip', 'b/')
name property:
>>> b.name
'b'
join with divide operator:
>>> c = b / 'c.txt'
>>> c
Path('abcde.zip', 'b/c.txt')
>>> c.name
'c.txt'
Read text:
>>> c.read_text()
'content of c'
existence:
>>> c.exists()
True
>>> (b / 'missing.txt').exists()
False
Coercion to string:
>>> str(c)
'abcde.zip/b/c.txt'
"""
__repr = "{self.__class__.__name__}({self.root.filename!r}, {self.at!r})"
def __init__(self, root, at=""):
self.root = (
root
if isinstance(root, zipfile.ZipFile)
else zipfile.ZipFile(self._pathlib_compat(root))
)
self.at = at
@staticmethod
def _pathlib_compat(path):
"""
For path-like objects, convert to a filename for compatibility
on Python 3.6.1 and earlier.
"""
try:
return path.__fspath__()
except AttributeError:
return str(path)
@property
def open(self):
return functools.partial(self.root.open, self.at)
@property
def name(self):
return posixpath.basename(self.at.rstrip("/"))
def read_text(self, *args, **kwargs):
with self.open() as strm:
return io.TextIOWrapper(strm, *args, **kwargs).read()
def read_bytes(self):
with self.open() as strm:
return strm.read()
def _is_child(self, path):
return posixpath.dirname(path.at.rstrip("/")) == self.at.rstrip("/")
def _next(self, at):
return Path(self.root, at)
def is_dir(self):
return not self.at or self.at.endswith("/")
def is_file(self):
return not self.is_dir()
def exists(self):
return self.at in self._names()
def iterdir(self):
if not self.is_dir():
raise ValueError("Can't listdir a file")
subs = map(self._next, self._names())
return filter(self._is_child, subs)
def __str__(self):
return posixpath.join(self.root.filename, self.at)
def __repr__(self):
return self.__repr.format(self=self)
def joinpath(self, add):
add = self._pathlib_compat(add)
next = posixpath.join(self.at, add)
next_dir = posixpath.join(self.at, add, "")
names = self._names()
return self._next(next_dir if next not in names and next_dir in names else next)
__truediv__ = joinpath
@staticmethod
def _implied_dirs(names):
return more_itertools.unique_everseen(
parent + "/"
for name in names
for parent in _parents(name)
if parent + "/" not in names
)
@classmethod
def _add_implied_dirs(cls, names):
return names + list(cls._implied_dirs(names))
@property
def parent(self):
parent_at = posixpath.dirname(self.at.rstrip('/'))
if parent_at:
parent_at += '/'
return self._next(parent_at)
def _names(self):
return self._add_implied_dirs(list(map(SanitizedNames._sanitize, self.root.namelist())))
if sys.version_info < (3,):
__div__ = __truediv__