10.10. shutil
— High-level file operations¶
Source code: Lib/shutil.py
The shutil
module offers a number of high-level operations on files and
collections of files. In particular, functions are provided which support file
copying and removal. For operations on individual files, see also the
os
module.
警告
Even the higher-level file copying functions (shutil.copy()
,
shutil.copy2()
) can’t copy all file metadata.
On POSIX platforms, this means that file owner and group are lost as well as ACLs. On Mac OS, the resource fork and other metadata are not used. This means that resources will be lost and file type and creator codes will not be correct. On Windows, file owners, ACLs and alternate data streams are not copied.
10.10.1. Directory and files operations¶
-
shutil.
copyfileobj
(fsrc, fdst[, length])¶ Copy the contents of the file-like object fsrc to the file-like object fdst. The integer length, if given, is the buffer size. In particular, a negative length value means to copy the data without looping over the source data in chunks; by default the data is read in chunks to avoid uncontrolled memory consumption. Note that if the current file position of the fsrc object is not 0, only the contents from the current file position to the end of the file will be copied.
-
shutil.
copyfile
(src, dst)¶ Copy the contents (no metadata) of the file named src to a file named dst. dst must be the complete target file name; look at
shutil.copy()
for a copy that accepts a target directory path. If src and dst are the same files,Error
is raised. The destination location must be writable; otherwise, anIOError
exception will be raised. If dst already exists, it will be replaced. Special files such as character or block devices and pipes cannot be copied with this function. src and dst are path names given as strings.
-
shutil.
copymode
(src, dst)¶ Copy the permission bits from src to dst. The file contents, owner, and group are unaffected. src and dst are path names given as strings.
-
shutil.
copystat
(src, dst)¶ Copy the permission bits, last access time, last modification time, and flags from src to dst. The file contents, owner, and group are unaffected. src and dst are path names given as strings.
-
shutil.
copy
(src, dst)¶ Copy the file src to the file or directory dst. If dst is a directory, a file with the same basename as src is created (or overwritten) in the directory specified. Permission bits are copied. src and dst are path names given as strings.
-
shutil.
copy2
(src, dst)¶ Identical to
copy()
except thatcopy2()
also attempts to preserve file metadata.copy2()
usescopystat()
to copy the file metadata. Please seecopystat()
for more information.
-
shutil.
ignore_patterns
(*patterns)¶ This factory function creates a function that can be used as a callable for
copytree()
’s ignore argument, ignoring files and directories that match one of the glob-style patterns provided. See the example below.2.6 新版功能.
-
shutil.
copytree
(src, dst, symlinks=False, ignore=None)¶ Recursively copy an entire directory tree rooted at src. The destination directory, named by dst, must not already exist; it will be created as well as missing parent directories. Permissions and times of directories are copied with
copystat()
, individual files are copied usingshutil.copy2()
.If symlinks is true, symbolic links in the source tree are represented as symbolic links in the new tree, but the metadata of the original links is NOT copied; if false or omitted, the contents and metadata of the linked files are copied to the new tree.
If ignore is given, it must be a callable that will receive as its arguments the directory being visited by
copytree()
, and a list of its contents, as returned byos.listdir()
. Sincecopytree()
is called recursively, the ignore callable will be called once for each directory that is copied. The callable must return a sequence of directory and file names relative to the current directory (i.e. a subset of the items in its second argument); these names will then be ignored in the copy process.ignore_patterns()
can be used to create such a callable that ignores names based on glob-style patterns.If exception(s) occur, an
Error
is raised with a list of reasons.The source code for this should be considered an example rather than the ultimate tool.
在 2.3 版更改:
Error
is raised if any exceptions occur during copying, rather than printing a message.在 2.5 版更改: Create intermediate directories needed to create dst, rather than raising an error. Copy permissions and times of directories using
copystat()
.在 2.6 版更改: Added the ignore argument to be able to influence what is being copied.
-
shutil.
rmtree
(path[, ignore_errors[, onerror]])¶ Delete an entire directory tree; path must point to a directory (but not a symbolic link to a directory). If ignore_errors is true, errors resulting from failed removals will be ignored; if false or omitted, such errors are handled by calling a handler specified by onerror or, if that is omitted, they raise an exception.
If onerror is provided, it must be a callable that accepts three parameters: function, path, and excinfo. The first parameter, function, is the function which raised the exception; it will be
os.path.islink()
,os.listdir()
,os.remove()
oros.rmdir()
. The second parameter, path, will be the path name passed to function. The third parameter, excinfo, will be the exception information return bysys.exc_info()
. Exceptions raised by onerror will not be caught.在 2.6 版更改: Explicitly check for path being a symbolic link and raise
OSError
in that case.
-
shutil.
move
(src, dst)¶ Recursively move a file or directory (src) to another location (dst).
If the destination is an existing directory, then src is moved inside that directory. If the destination already exists but is not a directory, it may be overwritten depending on
os.rename()
semantics.If the destination is on the current filesystem, then
os.rename()
is used. Otherwise, src is copied (usingshutil.copy2()
) to dst and then removed.2.3 新版功能.
-
exception
shutil.
Error
¶ This exception collects exceptions that are raised during a multi-file operation. For
copytree()
, the exception argument is a list of 3-tuples (srcname, dstname, exception).2.3 新版功能.
10.10.1.1. copytree example¶
This example is the implementation of the copytree()
function, described
above, with the docstring omitted. It demonstrates many of the other functions
provided by this module.
def copytree(src, dst, symlinks=False, ignore=None):
names = os.listdir(src)
if ignore is not None:
ignored_names = ignore(src, names)
else:
ignored_names = set()
os.makedirs(dst)
errors = []
for name in names:
if name in ignored_names:
continue
srcname = os.path.join(src, name)
dstname = os.path.join(dst, name)
try:
if symlinks and os.path.islink(srcname):
linkto = os.readlink(srcname)
os.symlink(linkto, dstname)
elif os.path.isdir(srcname):
copytree(srcname, dstname, symlinks, ignore)
else:
copy2(srcname, dstname)
# XXX What about devices, sockets etc.?
except (IOError, os.error) as why:
errors.append((srcname, dstname, str(why)))
# catch the Error from the recursive copytree so that we can
# continue with other files
except Error as err:
errors.extend(err.args[0])
try:
copystat(src, dst)
except WindowsError:
# can't copy file access times on Windows
pass
except OSError as why:
errors.extend((src, dst, str(why)))
if errors:
raise Error(errors)
Another example that uses the ignore_patterns()
helper:
from shutil import copytree, ignore_patterns
copytree(source, destination, ignore=ignore_patterns('*.pyc', 'tmp*'))
This will copy everything except .pyc
files and files or directories whose
name starts with tmp
.
Another example that uses the ignore argument to add a logging call:
from shutil import copytree
import logging
def _logpath(path, names):
logging.info('Working in %s' % path)
return [] # nothing will be ignored
copytree(source, destination, ignore=_logpath)
10.10.2. Archiving operations¶
High-level utilities to create and read compressed and archived files are also
provided. They rely on the zipfile
and tarfile
modules.
-
shutil.
make_archive
(base_name, format[, root_dir[, base_dir[, verbose[, dry_run[, owner[, group[, logger]]]]]]])¶ Create an archive file (eg. zip or tar) and returns its name.
base_name is the name of the file to create, including the path, minus any format-specific extension. format is the archive format: one of “zip” (if the
zlib
module or externalzip
executable is available), “tar”, “gztar” (if thezlib
module is available), or “bztar” (if thebz2
module is available).root_dir is a directory that will be the root directory of the archive; ie. we typically chdir into root_dir before creating the archive.
base_dir is the directory where we start archiving from; ie. base_dir will be the common prefix of all files and directories in the archive.
root_dir and base_dir both default to the current directory.
owner and group are used when creating a tar archive. By default, uses the current owner and group.
logger must be an object compatible with PEP 282, usually an instance of
logging.Logger
.2.7 新版功能.
-
shutil.
get_archive_formats
()¶ Return a list of supported formats for archiving. Each element of the returned sequence is a tuple
(name, description)
.By default
shutil
provides these formats:- zip: ZIP file (if the
zlib
module or externalzip
executable is available). - tar: uncompressed tar file.
- gztar: gzip’ed tar-file (if the
zlib
module is available). - bztar: bzip2’ed tar-file (if the
bz2
module is available).
You can register new formats or provide your own archiver for any existing formats, by using
register_archive_format()
.2.7 新版功能.
- zip: ZIP file (if the
-
shutil.
register_archive_format
(name, function[, extra_args[, description]])¶ Register an archiver for the format name. function is a callable that will be used to invoke the archiver.
If given, extra_args is a sequence of
(name, value)
that will be used as extra keywords arguments when the archiver callable is used.description is used by
get_archive_formats()
which returns the list of archivers. Defaults to an empty list.2.7 新版功能.
-
shutil.
unregister_archive_format
(name)¶ Remove the archive format name from the list of supported formats.
2.7 新版功能.
10.10.2.1. Archiving example¶
In this example, we create a gzip’ed tar-file archive containing all files
found in the .ssh
directory of the user:
>>> from shutil import make_archive
>>> import os
>>> archive_name = os.path.expanduser(os.path.join('~', 'myarchive'))
>>> root_dir = os.path.expanduser(os.path.join('~', '.ssh'))
>>> make_archive(archive_name, 'gztar', root_dir)
'/Users/tarek/myarchive.tar.gz'
The resulting archive contains:
$ tar -tzvf /Users/tarek/myarchive.tar.gz
drwx------ tarek/staff 0 2010-02-01 16:23:40 ./
-rw-r--r-- tarek/staff 609 2008-06-09 13:26:54 ./authorized_keys
-rwxr-xr-x tarek/staff 65 2008-06-09 13:26:54 ./config
-rwx------ tarek/staff 668 2008-06-09 13:26:54 ./id_dsa
-rwxr-xr-x tarek/staff 609 2008-06-09 13:26:54 ./id_dsa.pub
-rw------- tarek/staff 1675 2008-06-09 13:26:54 ./id_rsa
-rw-r--r-- tarek/staff 397 2008-06-09 13:26:54 ./id_rsa.pub
-rw-r--r-- tarek/staff 37192 2010-02-06 18:23:10 ./known_hosts