zipfile — Work with ZIP archives
New in version 1.6.
The ZIP file format is a common archive and compression standard. This module
provides tools to create, read, write, append, and list a ZIP file. Any
advanced use of this module will require an understanding of the format, as
defined in PKZIP Application Note.
This module does not currently handle multi-disk ZIP files, or ZIP files
which have appended comments (although it correctly handles comments
added to individual archive members—for which see the ZipInfo Objects
documentation). It can handle ZIP files that use the ZIP64 extensions
(that is ZIP files that are more than 4 GByte in size). It supports
decryption of encrypted files in ZIP archives, but it currently cannot
create an encrypted file. Decryption is extremely slow as it is
implemented in native python rather than C.
For other archive formats, see the bz2, gzip, and
tarfile modules.
The module defines the following items:
-
exception zipfile.BadZipfile
- The error raised for bad ZIP files (old name: zipfile.error).
-
exception zipfile.LargeZipFile
- The error raised when a ZIP file would require ZIP64 functionality but that has
not been enabled.
-
class zipfile.ZipFile
- The class for reading and writing ZIP files. See section
ZipFile Objects for constructor details.
-
class zipfile.PyZipFile
- Class for creating ZIP archives containing Python libraries.
-
class zipfile.ZipInfo([filename[, date_time]])
- Class used to represent information about a member of an archive. Instances
of this class are returned by the getinfo() and infolist()
methods of ZipFile objects. Most users of the zipfile module
will not need to create these, but only use those created by this
module. filename should be the full name of the archive member, and
date_time should be a tuple containing six fields which describe the time
of the last modification to the file; the fields are described in section
ZipInfo Objects.
-
zipfile.is_zipfile(filename)
- Returns True if filename is a valid ZIP file based on its magic number,
otherwise returns False. This module does not currently handle ZIP files
which have appended comments.
-
zipfile.ZIP_STORED
- The numeric constant for an uncompressed archive member.
-
zipfile.ZIP_DEFLATED
- The numeric constant for the usual ZIP compression method. This requires the
zlib module. No other compression methods are currently supported.
See also
- PKZIP Application Note
- Documentation on the ZIP file format by Phil Katz, the creator of the format and
algorithms used.
- Info-ZIP Home Page
- Information about the Info-ZIP project’s ZIP archive programs and development
libraries.
ZipFile Objects
-
class zipfile.ZipFile(file[, mode[, compression[, allowZip64]]])
Open a ZIP file, where file can be either a path to a file (a string) or a
file-like object. The mode parameter should be 'r' to read an existing
file, 'w' to truncate and write a new file, or 'a' to append to an
existing file. If mode is 'a' and file refers to an existing ZIP file,
then additional files are added to it. If file does not refer to a ZIP file,
then a new ZIP archive is appended to the file. This is meant for adding a ZIP
archive to another file, such as python.exe. Using
cat myzip.zip >> python.exe
also works, and at least WinZip can read such files. If mode is
a and the file does not exist at all, it is created. compression is the
ZIP compression method to use when writing the archive, and should be
ZIP_STORED or ZIP_DEFLATED; unrecognized values will cause
RuntimeError to be raised. If ZIP_DEFLATED is specified but the
zlib module is not available, RuntimeError is also raised. The
default is ZIP_STORED. If allowZip64 is True zipfile will create
ZIP files that use the ZIP64 extensions when the zipfile is larger than 2 GB. If
it is false (the default) zipfile will raise an exception when the ZIP
file would require ZIP64 extensions. ZIP64 extensions are disabled by default
because the default zip and unzip commands on Unix (the
InfoZIP utilities) don’t support these extensions.
Changed in version 2.6: If the file does not exist, it is created if the mode is ‘a’.
-
ZipFile.close()
- Close the archive file. You must call close() before exiting your program
or essential records will not be written.
-
ZipFile.getinfo(name)
- Return a ZipInfo object with information about the archive member
name. Calling getinfo() for a name not currently contained in the
archive will raise a KeyError.
-
ZipFile.infolist()
- Return a list containing a ZipInfo object for each member of the
archive. The objects are in the same order as their entries in the actual ZIP
file on disk if an existing archive was opened.
-
ZipFile.namelist()
- Return a list of archive members by name.
-
ZipFile.open(name[, mode[, pwd]])
Extract a member from the archive as a file-like object (ZipExtFile). name is
the name of the file in the archive, or a ZipInfo object. The mode
parameter, if included, must be one of the following: 'r' (the default),
'U', or 'rU'. Choosing 'U' or 'rU' will enable universal newline
support in the read-only object. pwd is the password used for encrypted files.
Calling open() on a closed ZipFile will raise a RuntimeError.
Note
The file-like object is read-only and provides the following methods:
read(), readline(), readlines(), __iter__(),
next().
Note
If the ZipFile was created by passing in a file-like object as the first
argument to the constructor, then the object returned by open() shares the
ZipFile’s file pointer. Under these circumstances, the object returned by
open() should not be used after any additional operations are performed
on the ZipFile object. If the ZipFile was created by passing in a string (the
filename) as the first argument to the constructor, then open() will
create a new file object that will be held by the ZipExtFile, allowing it to
operate independently of the ZipFile.
Note
The open(), read() and extract() methods can take a filename
or a ZipInfo object. You will appreciate this when trying to read a
ZIP file that contains members with duplicate names.
New in version 2.6.
Extract a member from the archive to the current working directory; member
must be its full name or a ZipInfo object). Its file information is
extracted as accurately as possible. path specifies a different directory
to extract to. member can be a filename or a ZipInfo object.
pwd is the password used for encrypted files.
New in version 2.6.
Extract all members from the archive to the current working directory. path
specifies a different directory to extract to. members is optional and must
be a subset of the list returned by namelist(). pwd is the password
used for encrypted files.
New in version 2.6.
-
ZipFile.printdir()
- Print a table of contents for the archive to sys.stdout.
-
ZipFile.setpassword(pwd)
Set pwd as default password to extract encrypted files.
New in version 2.6.
-
ZipFile.read(name[, pwd])
Return the bytes of the file name in the archive. name is the name of the
file in the archive, or a ZipInfo object. The archive must be open for
read or append. pwd is the password used for encrypted files and, if specified,
it will override the default password set with setpassword(). Calling
read() on a closed ZipFile will raise a RuntimeError.
Changed in version 2.6: pwd was added, and name can now be a ZipInfo object.
-
ZipFile.testzip()
- Read all the files in the archive and check their CRC’s and file headers.
Return the name of the first bad file, or else return None. Calling
testzip() on a closed ZipFile will raise a RuntimeError.
-
ZipFile.write(filename[, arcname[, compress_type]])
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 archive must be open with mode 'w' or 'a' – calling
write() on a ZipFile created with mode 'r' will raise a
RuntimeError. Calling write() on a closed ZipFile will raise a
RuntimeError.
Note
There is no official file name encoding for ZIP files. If you have unicode file
names, you must convert them to byte strings in your desired encoding before
passing them to write(). WinZip interprets all file names as encoded in
CP437, also known as DOS Latin.
Note
Archive names should be relative to the archive root, that is, they should not
start with a path separator.
Note
If arcname (or filename, if arcname is not given) contains a null
byte, the name of the file in the archive will be truncated at the null byte.
-
ZipFile.writestr(zinfo_or_arcname, bytes)
Write the string bytes to the archive; zinfo_or_arcname is either the file
name it will be given in the archive, or a ZipInfo instance. If it’s
an instance, at least the filename, date, and time must be given. If it’s a
name, the date and time is set to the current date and time. The archive must be
opened with mode 'w' or 'a' – calling writestr() on a ZipFile
created with mode 'r' will raise a RuntimeError. Calling
writestr() on a closed ZipFile will raise a RuntimeError.
Note
When passing a ZipInfo instance as the zinfo_or_acrname parameter,
the compression method used will be that specified in the compress_type
member of the given ZipInfo instance. By default, the
ZipInfo constructor sets this member to ZIP_STORED.
The following data attributes are also available:
-
ZipFile.debug
- The level of debug output to use. This may be set from 0 (the default, no
output) to 3 (the most output). Debugging information is written to
sys.stdout.
- The comment text associated with the ZIP file. If assigning a comment to a
ZipFile instance created with mode ‘a’ or ‘w’, this should be a
string no longer than 65535 bytes. Comments longer than this will be
truncated in the written archive when ZipFile.close() is called.
PyZipFile Objects
The PyZipFile constructor takes the same parameters as the
ZipFile constructor. Instances have one method in addition to those of
ZipFile objects.
-
PyZipFile.writepy(pathname[, basename])
Search for files *.py and add the corresponding file to the archive.
The corresponding file is a *.pyo file if available, else a
*.pyc file, compiling if necessary. If the pathname is a file, the
filename must end with .py, and just the (corresponding
*.py[co]) file is added at the top level (no path information). If the
pathname is a file that does not end with .py, a RuntimeError
will be raised. If it is a directory, and the directory is not a package
directory, then all the files *.py[co] are added at the top level. If
the directory is a package directory, then all *.py[co] are added under
the package name as a file path, and if any subdirectories are package
directories, all of these are added recursively. basename is intended for
internal use only. The writepy() method makes archives with file names
like this:
string.pyc # Top level name
test/__init__.pyc # Package directory
test/test_support.pyc # Module test.test_support
test/bogus/__init__.pyc # Subpackage directory
test/bogus/myfile.pyc # Submodule test.bogus.myfile
ZipInfo Objects
Instances of the ZipInfo class are returned by the getinfo() and
infolist() methods of ZipFile objects. Each object stores
information about a single member of the ZIP archive.
Instances have the following attributes:
-
ZipInfo.filename
- Name of the file in the archive.
-
ZipInfo.date_time
The time and date of the last modification to the archive member. This is a
tuple of six values:
Index |
Value |
0 |
Year |
1 |
Month (one-based) |
2 |
Day of month (one-based) |
3 |
Hours (zero-based) |
4 |
Minutes (zero-based) |
5 |
Seconds (zero-based) |
-
ZipInfo.compress_type
- Type of compression for the archive member.
- Comment for the individual archive member.
- Expansion field data. The PKZIP Application Note contains
some comments on the internal structure of the data contained in this string.
-
ZipInfo.create_system
- System which created ZIP archive.
-
ZipInfo.create_version
- PKZIP version which created ZIP archive.
- PKZIP version needed to extract archive.
-
ZipInfo.reserved
- Must be zero.
-
ZipInfo.flag_bits
- ZIP flag bits.
-
ZipInfo.volume
- Volume number of file header.
-
ZipInfo.internal_attr
- Internal attributes.
-
ZipInfo.external_attr
- External file attributes.
- Byte offset to the file header.
-
ZipInfo.CRC
- CRC-32 of the uncompressed file.
-
ZipInfo.compress_size
- Size of the compressed data.
-
ZipInfo.file_size
- Size of the uncompressed file.
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