From ce237c7d58ba207575cdfb0195a58a6407fbf717 Mon Sep 17 00:00:00 2001 From: Bo Bayles Date: Mon, 29 Jan 2018 23:54:07 -0600 Subject: [PATCH] bpo-21417: Add compresslevel= to the zipfile module (GH-5385) This allows the compression level to be specified when writing zipfiles (for the entire file *and* overridden on a per-file basis). Contributed by Bo Bayles --- Doc/library/zipfile.rst | 44 ++++++++++++++----- Lib/test/test_zipfile.py | 40 +++++++++++++++-- Lib/zipfile.py | 43 ++++++++++++++---- .../2018-01-28-07-55-10.bpo-21417.JFnV99.rst | 1 + 4 files changed, 104 insertions(+), 24 deletions(-) create mode 100644 Misc/NEWS.d/next/Library/2018-01-28-07-55-10.bpo-21417.JFnV99.rst diff --git a/Doc/library/zipfile.rst b/Doc/library/zipfile.rst index 5b8c776ed64..d58efe0b417 100644 --- a/Doc/library/zipfile.rst +++ b/Doc/library/zipfile.rst @@ -130,10 +130,12 @@ ZipFile Objects --------------- -.. class:: ZipFile(file, mode='r', compression=ZIP_STORED, allowZip64=True) +.. class:: ZipFile(file, mode='r', compression=ZIP_STORED, allowZip64=True, \ + compresslevel=None) Open a ZIP file, where *file* can be a path to a file (a string), a file-like object or a :term:`path-like object`. + The *mode* parameter should be ``'r'`` to read an existing file, ``'w'`` to truncate and write a new file, ``'a'`` to append to an existing file, or ``'x'`` to exclusively create and write a new file. @@ -145,16 +147,27 @@ ZipFile Objects adding a ZIP archive to another file (such as :file:`python.exe`). If *mode* is ``'a'`` and the file does not exist at all, it is created. If *mode* is ``'r'`` or ``'a'``, the file should be seekable. + *compression* is the ZIP compression method to use when writing the archive, and should be :const:`ZIP_STORED`, :const:`ZIP_DEFLATED`, :const:`ZIP_BZIP2` or :const:`ZIP_LZMA`; unrecognized - values will cause :exc:`NotImplementedError` to be raised. If :const:`ZIP_DEFLATED`, - :const:`ZIP_BZIP2` or :const:`ZIP_LZMA` is specified but the corresponding module - (:mod:`zlib`, :mod:`bz2` or :mod:`lzma`) is not available, :exc:`RuntimeError` - is raised. The default is :const:`ZIP_STORED`. If *allowZip64* is - ``True`` (the default) zipfile will create ZIP files that use the ZIP64 - extensions when the zipfile is larger than 4 GiB. If it is false :mod:`zipfile` - will raise an exception when the ZIP file would require ZIP64 extensions. + values will cause :exc:`NotImplementedError` to be raised. If + :const:`ZIP_DEFLATED`, :const:`ZIP_BZIP2` or :const:`ZIP_LZMA` is specified + but the corresponding module (:mod:`zlib`, :mod:`bz2` or :mod:`lzma`) is not + available, :exc:`RuntimeError` is raised. The default is :const:`ZIP_STORED`. + + If *allowZip64* is ``True`` (the default) zipfile will create ZIP files that + use the ZIP64 extensions when the zipfile is larger than 4 GiB. If it is + ``false`` :mod:`zipfile` will raise an exception when the ZIP file would + require ZIP64 extensions. + + The *compresslevel* parameter controls the compression level to use when + writing files to the archive. + When using :const:`ZIP_STORED` or :const:`ZIP_LZMA` it has no effect. + When using :const:`ZIP_DEFLATED` integers ``0`` through ``9`` are accepted + (see :class:`zlib ` for more information). + When using :const:`ZIP_BZIP2` integers ``1`` through ``9`` are accepted + (see :class:`bz2 ` for more information). If the file is created with mode ``'w'``, ``'x'`` or ``'a'`` and then :meth:`closed ` without adding any files to the archive, the appropriate @@ -187,6 +200,9 @@ ZipFile Objects .. versionchanged:: 3.6.2 The *file* parameter accepts a :term:`path-like object`. + .. versionchanged:: 3.7 + Add the *compresslevel* parameter. + .. method:: ZipFile.close() @@ -351,13 +367,15 @@ ZipFile Objects :exc:`ValueError`. Previously, a :exc:`RuntimeError` was raised. -.. method:: ZipFile.write(filename, arcname=None, compress_type=None) +.. method:: ZipFile.write(filename, arcname=None, compress_type=None, \ + compresslevel=None) Write the file named *filename* to the archive, giving it the archive name *arcname* (by default, this will be the same as *filename*, but without a drive letter and with leading path separators removed). If given, *compress_type* overrides the value given for the *compression* parameter to the constructor for - the new entry. + the new entry. Similarly, *compresslevel* will override the constructor if + given. The archive must be open with mode ``'w'``, ``'x'`` or ``'a'``. .. note:: @@ -383,7 +401,8 @@ ZipFile Objects a :exc:`RuntimeError` was raised. -.. method:: ZipFile.writestr(zinfo_or_arcname, data[, compress_type]) +.. method:: ZipFile.writestr(zinfo_or_arcname, data, compress_type=None, \ + compresslevel=None) Write the string *data* to the archive; *zinfo_or_arcname* is either the file name it will be given in the archive, or a :class:`ZipInfo` instance. If it's @@ -393,7 +412,8 @@ ZipFile Objects If given, *compress_type* overrides the value given for the *compression* parameter to the constructor for the new entry, or in the *zinfo_or_arcname* - (if that is a :class:`ZipInfo` instance). + (if that is a :class:`ZipInfo` instance). Similarly, *compresslevel* will + override the constructor if given. .. note:: diff --git a/Lib/test/test_zipfile.py b/Lib/test/test_zipfile.py index 3bc867ea51c..94db858a151 100644 --- a/Lib/test/test_zipfile.py +++ b/Lib/test/test_zipfile.py @@ -53,9 +53,10 @@ class AbstractTestsWithSourceFile: with open(TESTFN, "wb") as fp: fp.write(self.data) - def make_test_archive(self, f, compression): + def make_test_archive(self, f, compression, compresslevel=None): + kwargs = {'compression': compression, 'compresslevel': compresslevel} # Create the ZIP archive - with zipfile.ZipFile(f, "w", compression) as zipfp: + with zipfile.ZipFile(f, "w", **kwargs) as zipfp: zipfp.write(TESTFN, "another.name") zipfp.write(TESTFN, TESTFN) zipfp.writestr("strfile", self.data) @@ -63,8 +64,8 @@ class AbstractTestsWithSourceFile: for line in self.line_gen: f.write(line) - def zip_test(self, f, compression): - self.make_test_archive(f, compression) + def zip_test(self, f, compression, compresslevel=None): + self.make_test_archive(f, compression, compresslevel) # Read the ZIP archive with zipfile.ZipFile(f, "r", compression) as zipfp: @@ -297,6 +298,22 @@ class AbstractTestsWithSourceFile: info = zipfp.getinfo('b.txt') self.assertEqual(info.compress_type, self.compression) + def test_writestr_compresslevel(self): + zipfp = zipfile.ZipFile(TESTFN2, "w", compresslevel=1) + zipfp.writestr("a.txt", "hello world", compress_type=self.compression) + zipfp.writestr("b.txt", "hello world", compress_type=self.compression, + compresslevel=2) + + # Compression level follows the constructor. + a_info = zipfp.getinfo('a.txt') + self.assertEqual(a_info.compress_type, self.compression) + self.assertEqual(a_info._compresslevel, 1) + + # Compression level is overridden. + b_info = zipfp.getinfo('b.txt') + self.assertEqual(b_info.compress_type, self.compression) + self.assertEqual(b_info._compresslevel, 2) + def test_read_return_size(self): # Issue #9837: ZipExtFile.read() shouldn't return more bytes # than requested. @@ -370,6 +387,21 @@ class AbstractTestsWithSourceFile: self.assertIn('[closed]', repr(zipopen)) self.assertIn('[closed]', repr(zipfp)) + def test_compresslevel_basic(self): + for f in get_files(self): + self.zip_test(f, self.compression, compresslevel=9) + + def test_per_file_compresslevel(self): + """Check that files within a Zip archive can have different + compression levels.""" + with zipfile.ZipFile(TESTFN2, "w", compresslevel=1) as zipfp: + zipfp.write(TESTFN, 'compress_1') + zipfp.write(TESTFN, 'compress_9', compresslevel=9) + one_info = zipfp.getinfo('compress_1') + nine_info = zipfp.getinfo('compress_9') + self.assertEqual(one_info._compresslevel, 1) + self.assertEqual(nine_info._compresslevel, 9) + def tearDown(self): unlink(TESTFN) unlink(TESTFN2) diff --git a/Lib/zipfile.py b/Lib/zipfile.py index 37ce3281e09..f9db45f58a2 100644 --- a/Lib/zipfile.py +++ b/Lib/zipfile.py @@ -295,6 +295,7 @@ class ZipInfo (object): 'filename', 'date_time', 'compress_type', + '_compresslevel', 'comment', 'extra', 'create_system', @@ -334,6 +335,7 @@ class ZipInfo (object): # Standard values: self.compress_type = ZIP_STORED # Type of compression for the file + self._compresslevel = None # Level for the compressor self.comment = b"" # Comment for each file self.extra = b"" # ZIP extra data if sys.platform == 'win32': @@ -654,12 +656,16 @@ def _check_compression(compression): raise NotImplementedError("That compression method is not supported") -def _get_compressor(compress_type): +def _get_compressor(compress_type, compresslevel=None): if compress_type == ZIP_DEFLATED: - return zlib.compressobj(zlib.Z_DEFAULT_COMPRESSION, - zlib.DEFLATED, -15) + if compresslevel is not None: + return zlib.compressobj(compresslevel, zlib.DEFLATED, -15) + return zlib.compressobj(zlib.Z_DEFAULT_COMPRESSION, zlib.DEFLATED, -15) elif compress_type == ZIP_BZIP2: + if compresslevel is not None: + return bz2.BZ2Compressor(compresslevel) return bz2.BZ2Compressor() + # compresslevel is ignored for ZIP_LZMA elif compress_type == ZIP_LZMA: return LZMACompressor() else: @@ -963,7 +969,8 @@ class _ZipWriteFile(io.BufferedIOBase): self._zinfo = zinfo self._zip64 = zip64 self._zipfile = zf - self._compressor = _get_compressor(zinfo.compress_type) + self._compressor = _get_compressor(zinfo.compress_type, + zinfo._compresslevel) self._file_size = 0 self._compress_size = 0 self._crc = 0 @@ -1035,7 +1042,8 @@ class _ZipWriteFile(io.BufferedIOBase): class ZipFile: """ Class with methods to open, read, write, close, list zip files. - z = ZipFile(file, mode="r", compression=ZIP_STORED, allowZip64=True) + z = ZipFile(file, mode="r", compression=ZIP_STORED, allowZip64=True, + compresslevel=None) file: Either the path to the file, or a file-like object. If it is a path, the file will be opened and closed by ZipFile. @@ -1046,13 +1054,19 @@ class ZipFile: allowZip64: if True ZipFile will create files with ZIP64 extensions when needed, otherwise it will raise an exception when this would be necessary. + compresslevel: None (default for the given compression type) or an integer + specifying the level to pass to the compressor. + When using ZIP_STORED or ZIP_LZMA this keyword has no effect. + When using ZIP_DEFLATED integers 0 through 9 are accepted. + When using ZIP_BZIP2 integers 1 through 9 are accepted. """ fp = None # Set here since __del__ checks it _windows_illegal_name_trans_table = None - def __init__(self, file, mode="r", compression=ZIP_STORED, allowZip64=True): + def __init__(self, file, mode="r", compression=ZIP_STORED, allowZip64=True, + compresslevel=None): """Open the ZIP file with mode read 'r', write 'w', exclusive create 'x', or append 'a'.""" if mode not in ('r', 'w', 'x', 'a'): @@ -1066,6 +1080,7 @@ class ZipFile: self.NameToInfo = {} # Find file info given name self.filelist = [] # List of ZipInfo instances for archive self.compression = compression # Method of compression + self.compresslevel = compresslevel self.mode = mode self.pwd = None self._comment = b'' @@ -1342,6 +1357,7 @@ class ZipFile: elif mode == 'w': zinfo = ZipInfo(name) zinfo.compress_type = self.compression + zinfo._compresslevel = self.compresslevel else: # Get info object for name zinfo = self.getinfo(name) @@ -1575,7 +1591,8 @@ class ZipFile: raise LargeZipFile(requires_zip64 + " would require ZIP64 extensions") - def write(self, filename, arcname=None, compress_type=None): + def write(self, filename, arcname=None, + compress_type=None, compresslevel=None): """Put the bytes from filename into the archive under the name arcname.""" if not self.fp: @@ -1597,6 +1614,11 @@ class ZipFile: else: zinfo.compress_type = self.compression + if compresslevel is not None: + zinfo._compresslevel = compresslevel + else: + zinfo._compresslevel = self.compresslevel + if zinfo.is_dir(): with self._lock: if self._seekable: @@ -1617,7 +1639,8 @@ class ZipFile: with open(filename, "rb") as src, self.open(zinfo, 'w') as dest: shutil.copyfileobj(src, dest, 1024*8) - def writestr(self, zinfo_or_arcname, data, compress_type=None): + def writestr(self, zinfo_or_arcname, data, + compress_type=None, compresslevel=None): """Write a file into the archive. The contents is 'data', which may be either a 'str' or a 'bytes' instance; if it is a 'str', it is encoded as UTF-8 first. @@ -1629,6 +1652,7 @@ class ZipFile: zinfo = ZipInfo(filename=zinfo_or_arcname, date_time=time.localtime(time.time())[:6]) zinfo.compress_type = self.compression + zinfo._compresslevel = self.compresslevel if zinfo.filename[-1] == '/': zinfo.external_attr = 0o40775 << 16 # drwxrwxr-x zinfo.external_attr |= 0x10 # MS-DOS directory flag @@ -1648,6 +1672,9 @@ class ZipFile: if compress_type is not None: zinfo.compress_type = compress_type + if compresslevel is not None: + zinfo._compresslevel = compresslevel + zinfo.file_size = len(data) # Uncompressed size with self._lock: with self.open(zinfo, mode='w') as dest: diff --git a/Misc/NEWS.d/next/Library/2018-01-28-07-55-10.bpo-21417.JFnV99.rst b/Misc/NEWS.d/next/Library/2018-01-28-07-55-10.bpo-21417.JFnV99.rst new file mode 100644 index 00000000000..50207a0e4c3 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2018-01-28-07-55-10.bpo-21417.JFnV99.rst @@ -0,0 +1 @@ +Added support for setting the compression level for zipfile.ZipFile.