CasperSecurity
# Copyright (c) Twisted Matrix Laboratories.
# See LICENSE for details.
"""
Tests for L{twisted.python.zipstream}
"""
import random
import struct
import zipfile
from hashlib import md5
from twisted.python import filepath, zipstream
from twisted.trial import unittest
class FileEntryMixin:
"""
File entry classes should behave as file-like objects
"""
def getFileEntry(self, contents):
"""
Return an appropriate zip file entry
"""
filename = self.mktemp()
with zipfile.ZipFile(filename, "w", self.compression) as z:
z.writestr("content", contents)
z = zipstream.ChunkingZipFile(filename, "r")
return z.readfile("content")
def test_isatty(self):
"""
zip files should not be ttys, so isatty() should be false
"""
with self.getFileEntry("") as fileEntry:
self.assertFalse(fileEntry.isatty())
def test_closed(self):
"""
The C{closed} attribute should reflect whether C{close()} has been
called.
"""
with self.getFileEntry("") as fileEntry:
self.assertFalse(fileEntry.closed)
self.assertTrue(fileEntry.closed)
def test_readline(self):
"""
C{readline()} should mirror L{file.readline} and return up to a single
delimiter.
"""
with self.getFileEntry(b"hoho\nho") as fileEntry:
self.assertEqual(fileEntry.readline(), b"hoho\n")
self.assertEqual(fileEntry.readline(), b"ho")
self.assertEqual(fileEntry.readline(), b"")
def test_next(self):
"""
Zip file entries should implement the iterator protocol as files do.
"""
with self.getFileEntry(b"ho\nhoho") as fileEntry:
self.assertEqual(fileEntry.next(), b"ho\n")
self.assertEqual(fileEntry.next(), b"hoho")
self.assertRaises(StopIteration, fileEntry.next)
def test_readlines(self):
"""
C{readlines()} should return a list of all the lines.
"""
with self.getFileEntry(b"ho\nho\nho") as fileEntry:
self.assertEqual(fileEntry.readlines(), [b"ho\n", b"ho\n", b"ho"])
def test_iteration(self):
"""
C{__iter__()} and C{xreadlines()} should return C{self}.
"""
with self.getFileEntry("") as fileEntry:
self.assertIs(iter(fileEntry), fileEntry)
self.assertIs(fileEntry.xreadlines(), fileEntry)
def test_readWhole(self):
"""
C{.read()} should read the entire file.
"""
contents = b"Hello, world!"
with self.getFileEntry(contents) as entry:
self.assertEqual(entry.read(), contents)
def test_readPartial(self):
"""
C{.read(num)} should read num bytes from the file.
"""
contents = "0123456789"
with self.getFileEntry(contents) as entry:
one = entry.read(4)
two = entry.read(200)
self.assertEqual(one, b"0123")
self.assertEqual(two, b"456789")
def test_tell(self):
"""
C{.tell()} should return the number of bytes that have been read so
far.
"""
contents = "x" * 100
with self.getFileEntry(contents) as entry:
entry.read(2)
self.assertEqual(entry.tell(), 2)
entry.read(4)
self.assertEqual(entry.tell(), 6)
class DeflatedZipFileEntryTests(FileEntryMixin, unittest.TestCase):
"""
DeflatedZipFileEntry should be file-like
"""
compression = zipfile.ZIP_DEFLATED
class ZipFileEntryTests(FileEntryMixin, unittest.TestCase):
"""
ZipFileEntry should be file-like
"""
compression = zipfile.ZIP_STORED
class ZipstreamTests(unittest.TestCase):
"""
Tests for twisted.python.zipstream
"""
def setUp(self):
"""
Creates junk data that can be compressed and a test directory for any
files that will be created
"""
self.testdir = filepath.FilePath(self.mktemp())
self.testdir.makedirs()
self.unzipdir = self.testdir.child("unzipped")
self.unzipdir.makedirs()
def makeZipFile(self, contents, directory=""):
"""
Makes a zip file archive containing len(contents) files. Contents
should be a list of strings, each string being the content of one file.
"""
zpfilename = self.testdir.child("zipfile.zip").path
with zipfile.ZipFile(zpfilename, "w") as zpfile:
for i, content in enumerate(contents):
filename = str(i)
if directory:
filename = directory + "/" + filename
zpfile.writestr(filename, content)
return zpfilename
def test_invalidMode(self):
"""
A ChunkingZipFile opened in write-mode should not allow .readfile(),
and raise a RuntimeError instead.
"""
with zipstream.ChunkingZipFile(self.mktemp(), "w") as czf:
self.assertRaises(RuntimeError, czf.readfile, "something")
def test_closedArchive(self):
"""
A closed ChunkingZipFile should raise a L{RuntimeError} when
.readfile() is invoked.
"""
czf = zipstream.ChunkingZipFile(self.makeZipFile(["something"]), "r")
czf.close()
self.assertRaises(RuntimeError, czf.readfile, "something")
def test_invalidHeader(self):
"""
A zipfile entry with the wrong magic number should raise BadZipfile for
readfile(), but that should not affect other files in the archive.
"""
fn = self.makeZipFile(["test contents", "more contents"])
with zipfile.ZipFile(fn, "r") as zf:
zeroOffset = zf.getinfo("0").header_offset
# Zero out just the one header.
with open(fn, "r+b") as scribble:
scribble.seek(zeroOffset, 0)
scribble.write(b"0" * 4)
with zipstream.ChunkingZipFile(fn) as czf:
self.assertRaises(zipfile.BadZipfile, czf.readfile, "0")
with czf.readfile("1") as zfe:
self.assertEqual(zfe.read(), b"more contents")
def test_filenameMismatch(self):
"""
A zipfile entry with a different filename than is found in the central
directory should raise BadZipfile.
"""
fn = self.makeZipFile([b"test contents", b"more contents"])
with zipfile.ZipFile(fn, "r") as zf:
info = zf.getinfo("0")
info.filename = "not zero"
with open(fn, "r+b") as scribble:
scribble.seek(info.header_offset, 0)
scribble.write(info.FileHeader())
with zipstream.ChunkingZipFile(fn) as czf:
self.assertRaises(zipfile.BadZipfile, czf.readfile, "0")
with czf.readfile("1") as zfe:
self.assertEqual(zfe.read(), b"more contents")
def test_unsupportedCompression(self):
"""
A zipfile which describes an unsupported compression mechanism should
raise BadZipfile.
"""
fn = self.mktemp()
with zipfile.ZipFile(fn, "w") as zf:
zi = zipfile.ZipInfo("0")
zf.writestr(zi, "some data")
# Mangle its compression type in the central directory; can't do
# this before the writestr call or zipfile will (correctly) tell us
# not to pass bad compression types :)
zi.compress_type = 1234
with zipstream.ChunkingZipFile(fn) as czf:
self.assertRaises(zipfile.BadZipfile, czf.readfile, "0")
def test_extraData(self):
"""
readfile() should skip over 'extra' data present in the zip metadata.
"""
fn = self.mktemp()
with zipfile.ZipFile(fn, "w") as zf:
zi = zipfile.ZipInfo("0")
extra_data = b"hello, extra"
zi.extra = struct.pack("<hh", 42, len(extra_data)) + extra_data
zf.writestr(zi, b"the real data")
with zipstream.ChunkingZipFile(fn) as czf, czf.readfile("0") as zfe:
self.assertEqual(zfe.read(), b"the real data")
def test_unzipIterChunky(self):
"""
L{twisted.python.zipstream.unzipIterChunky} returns an iterator which
must be exhausted to completely unzip the input archive.
"""
numfiles = 10
contents = ["This is test file %d!" % i for i in range(numfiles)]
contents = [i.encode("ascii") for i in contents]
zpfilename = self.makeZipFile(contents)
list(zipstream.unzipIterChunky(zpfilename, self.unzipdir.path))
self.assertEqual(set(self.unzipdir.listdir()), set(map(str, range(numfiles))))
for child in self.unzipdir.children():
num = int(child.basename())
self.assertEqual(child.getContent(), contents[num])
def test_unzipIterChunkyDirectory(self):
"""
The path to which a file is extracted by L{zipstream.unzipIterChunky}
is determined by joining the C{directory} argument to C{unzip} with the
path within the archive of the file being extracted.
"""
numfiles = 10
contents = ["This is test file %d!" % i for i in range(numfiles)]
contents = [i.encode("ascii") for i in contents]
zpfilename = self.makeZipFile(contents, "foo")
list(zipstream.unzipIterChunky(zpfilename, self.unzipdir.path))
fileContents = {str(num).encode("ascii") for num in range(numfiles)}
self.assertEqual(set(self.unzipdir.child(b"foo").listdir()), fileContents)
for child in self.unzipdir.child(b"foo").children():
num = int(child.basename())
self.assertEqual(child.getContent(), contents[num])
# XXX these tests are kind of gross and old, but I think unzipIterChunky is
# kind of a gross function anyway. We should really write an abstract
# copyTo/moveTo that operates on FilePath and make sure ZipPath can support
# it, then just deprecate / remove this stuff.
def _unzipIterChunkyTest(self, compression, chunksize, lower, upper):
"""
unzipIterChunky should unzip the given number of bytes per iteration.
"""
junk = b""
for n in range(1000):
num = round(random.random(), 12)
numEncoded = str(num).encode("ascii")
junk += b" " + numEncoded
junkmd5 = md5(junk).hexdigest()
tempdir = filepath.FilePath(self.mktemp())
tempdir.makedirs()
zfpath = tempdir.child("bigfile.zip").path
self._makebigfile(zfpath, compression, junk)
uziter = zipstream.unzipIterChunky(zfpath, tempdir.path, chunksize=chunksize)
r = next(uziter)
# test that the number of chunks is in the right ballpark;
# this could theoretically be any number but statistically it
# should always be in this range
approx = lower < r < upper
self.assertTrue(approx)
for r in uziter:
pass
self.assertEqual(r, 0)
with tempdir.child("zipstreamjunk").open() as f:
newmd5 = md5(f.read()).hexdigest()
self.assertEqual(newmd5, junkmd5)
def test_unzipIterChunkyStored(self):
"""
unzipIterChunky should unzip the given number of bytes per iteration on
a stored archive.
"""
self._unzipIterChunkyTest(zipfile.ZIP_STORED, 500, 35, 45)
def test_chunkyDeflated(self):
"""
unzipIterChunky should unzip the given number of bytes per iteration on
a deflated archive.
"""
self._unzipIterChunkyTest(zipfile.ZIP_DEFLATED, 972, 23, 27)
def _makebigfile(self, filename, compression, junk):
"""
Create a zip file with the given file name and compression scheme.
"""
with zipfile.ZipFile(filename, "w", compression) as zf:
for i in range(10):
fn = "zipstream%d" % i
zf.writestr(fn, "")
zf.writestr("zipstreamjunk", junk)