Source code for fs.tarfs

"""Manage the filesystem in a Tar archive.
"""

from __future__ import print_function
from __future__ import unicode_literals

import copy
import os
import tarfile
import typing
from collections import OrderedDict
from typing import cast, IO

import six

from . import errors
from .base import FS
from .compress import write_tar
from .enums import ResourceType
from .info import Info
from .iotools import RawWrapper
from .opener import open_fs
from .path import dirname, relpath, basename, isbase, parts, frombase
from .wrapfs import WrapFS
from .permissions import Permissions


if False:  # typing.TYPE_CHECKING
    from tarfile import TarInfo
    from typing import (
        Any,
        AnyStr,
        BinaryIO,
        Collection,
        Dict,
        List,
        Optional,
        Text,
        Tuple,
        Union,
    )
    from .info import Info, RawInfo
    from .permissions import Permissions
    from .subfs import SubFS

    T = typing.TypeVar("T", bound="ReadTarFS")


__all__ = ["TarFS", "WriteTarFS", "ReadTarFS"]


if six.PY2:

    def _get_member_info(member, encoding):
        # type: (TarInfo, Text) -> Dict[Text, object]
        return member.get_info(encoding, None)


else:

    def _get_member_info(member, encoding):
        # type: (TarInfo, Text) -> Dict[Text, object]
        # NOTE(@althonos): TarInfo.get_info is neither in the doc nor
        #     in the `tarfile` stub, and yet it exists and is public !
        return member.get_info()  # type: ignore


[docs]class TarFS(WrapFS): """Read and write tar files. There are two ways to open a TarFS for the use cases of reading a tar file, and creating a new one. If you open the TarFS with ``write`` set to `False` (the default), then the filesystem will be a read only filesystem which maps to the files and directories within the tar file. Files are decompressed on the fly when you open them. Here's how you might extract and print a readme from a tar file:: with TarFS('foo.tar.gz') as tar_fs: readme = tar_fs.readtext('readme.txt') If you open the TarFS with ``write`` set to `True`, then the TarFS will be a empty temporary filesystem. Any files / directories you create in the TarFS will be written in to a tar file when the TarFS is closed. The compression is set from the new file name but may be set manually with the ``compression`` argument. Here's how you might write a new tar file containing a readme.txt file:: with TarFS('foo.tar.xz', write=True) as new_tar: new_tar.writetext( 'readme.txt', 'This tar file was written by PyFilesystem' ) Arguments: file (str or io.IOBase): An OS filename, or an open file handle. write (bool): Set to `True` to write a new tar file, or use default (`False`) to read an existing tar file. compression (str, optional): Compression to use (one of the formats supported by `tarfile`: ``xz``, ``gz``, ``bz2``, or `None`). temp_fs (str): An FS URL for the temporary filesystem used to store data prior to tarring. """ _compression_formats = { # FMT #UNIX #MSDOS "xz": (".tar.xz", ".txz"), "bz2": (".tar.bz2", ".tbz"), "gz": (".tar.gz", ".tgz"), } def __new__( cls, file, # type: Union[Text, BinaryIO] write=False, # type: bool compression=None, # type: Optional[Text] encoding="utf-8", # type: Text temp_fs="temp://__tartemp__", # type: Text ): # type: (...) -> FS if isinstance(file, (six.text_type, six.binary_type)): file = os.path.expanduser(file) filename = file # type: Text else: filename = getattr(file, "name", "") if write and compression is None: compression = None for comp, extensions in six.iteritems(cls._compression_formats): if filename.endswith(extensions): compression = comp break if write: return WriteTarFS( file, compression=compression, encoding=encoding, temp_fs=temp_fs ) else: return ReadTarFS(file, encoding=encoding) if False: # typing.TYPE_CHECKING def __init__( self, file, # type: Union[Text, BinaryIO] write=False, # type: bool compression=None, # type: Optional[Text] encoding="utf-8", # type: Text temp_fs="temp://__tartemp__", # type: Text ): # type: (...) -> None pass
[docs]@six.python_2_unicode_compatible class WriteTarFS(WrapFS): """A writable tar file. """ def __init__( self, file, # type: Union[Text, BinaryIO] compression=None, # type: Optional[Text] encoding="utf-8", # type: Text temp_fs="temp://__tartemp__", # type: Text ): # type: (...) -> None self._file = file # type: Union[Text, BinaryIO] self.compression = compression self.encoding = encoding self._temp_fs_url = temp_fs self._temp_fs = open_fs(temp_fs) self._meta = dict(self._temp_fs.getmeta()) # type: ignore super(WriteTarFS, self).__init__(self._temp_fs) def __repr__(self): # type: () -> Text t = "WriteTarFS({!r}, compression={!r}, encoding={!r}, temp_fs={!r})" return t.format(self._file, self.compression, self.encoding, self._temp_fs_url) def __str__(self): # type: () -> Text return "<TarFS-write '{}'>".format(self._file) def delegate_path(self, path): # type: (Text) -> Tuple[FS, Text] return self._temp_fs, path def delegate_fs(self): # type: () -> FS return self._temp_fs def close(self): # type: () -> None if not self.isclosed(): try: self.write_tar() finally: self._temp_fs.close() super(WriteTarFS, self).close()
[docs] def write_tar( self, file=None, # type: Union[Text, BinaryIO, None] compression=None, # type: Optional[Text] encoding=None, # type: Optional[Text] ): # type: (...) -> None """Write tar to a file. Arguments: file (str or io.IOBase, optional): Destination file, may be a file name or an open file object. compression (str, optional): Compression to use (one of the constants defined in `tarfile` in the stdlib). encoding (str, optional): The character encoding to use (default uses the encoding defined in `~WriteTarFS.__init__`). Note: This is called automatically when the TarFS is closed. """ if not self.isclosed(): write_tar( self._temp_fs, file or self._file, compression=compression or self.compression, encoding=encoding or self.encoding, )
[docs]@six.python_2_unicode_compatible class ReadTarFS(FS): """A readable tar file. """ _meta = { "case_insensitive": True, "network": False, "read_only": True, "supports_rename": False, "thread_safe": True, "unicode_paths": True, "virtual": False, } _typemap = type_map = { tarfile.BLKTYPE: ResourceType.block_special_file, tarfile.CHRTYPE: ResourceType.character, tarfile.DIRTYPE: ResourceType.directory, tarfile.FIFOTYPE: ResourceType.fifo, tarfile.REGTYPE: ResourceType.file, tarfile.AREGTYPE: ResourceType.file, tarfile.SYMTYPE: ResourceType.symlink, tarfile.CONTTYPE: ResourceType.file, tarfile.LNKTYPE: ResourceType.symlink, } @errors.CreateFailed.catch_all def __init__(self, file, encoding="utf-8"): # type: (Union[Text, BinaryIO], Text) -> None super(ReadTarFS, self).__init__() self._file = file self.encoding = encoding if isinstance(file, (six.text_type, six.binary_type)): self._tar = tarfile.open(file, mode="r") else: self._tar = tarfile.open(fileobj=file, mode="r") self._directory = OrderedDict( (relpath(self._decode(info.name)).rstrip("/"), info) for info in self._tar ) def __repr__(self): # type: () -> Text return "ReadTarFS({!r})".format(self._file) def __str__(self): # type: () -> Text return "<TarFS '{}'>".format(self._file) if six.PY2: def _encode(self, s): # type: (Text) -> str return s.encode(self.encoding) def _decode(self, s): # type: (str) -> Text return s.decode(self.encoding) else: def _encode(self, s): # type: (Text) -> str return s def _decode(self, s): # type: (str) -> Text return s def getinfo(self, path, namespaces=None): # type: (Text, Optional[Collection[Text]]) -> Info _path = relpath(self.validatepath(path)) namespaces = namespaces or () raw_info = {} # type: Dict[Text, Dict[Text, object]] if not _path: raw_info["basic"] = {"name": "", "is_dir": True} if "details" in namespaces: raw_info["details"] = {"type": int(ResourceType.directory)} else: try: implicit = False member = self._tar.getmember(self._encode(_path)) except KeyError: if not self.isdir(_path): raise errors.ResourceNotFound(path) implicit = True member = tarfile.TarInfo(_path) member.type = tarfile.DIRTYPE raw_info["basic"] = { "name": basename(self._decode(member.name)), "is_dir": member.isdir(), } if "details" in namespaces: raw_info["details"] = { "size": member.size, "type": int(self.type_map[member.type]), } if not implicit: raw_info["details"]["modified"] = member.mtime if "access" in namespaces and not implicit: raw_info["access"] = { "gid": member.gid, "group": member.gname, "permissions": Permissions(mode=member.mode).dump(), "uid": member.uid, "user": member.uname, } if "tar" in namespaces and not implicit: raw_info["tar"] = _get_member_info(member, self.encoding) raw_info["tar"].update( { k.replace("is", "is_"): getattr(member, k)() for k in dir(member) if k.startswith("is") } ) return Info(raw_info) def isdir(self, path): _path = relpath(self.validatepath(path)) try: return self._directory[_path].isdir() except KeyError: return any(isbase(_path, name) for name in self._directory) def isfile(self, path): _path = relpath(self.validatepath(path)) try: return self._directory[_path].isfile() except KeyError: return False def setinfo(self, path, info): # type: (Text, RawInfo) -> None self.check() raise errors.ResourceReadOnly(path) def listdir(self, path): # type: (Text) -> List[Text] _path = relpath(self.validatepath(path)) if not self.gettype(path) is ResourceType.directory: raise errors.DirectoryExpected(path) children = (frombase(_path, n) for n in self._directory if isbase(_path, n)) content = (parts(child)[1] for child in children if relpath(child)) return list(OrderedDict.fromkeys(content)) def makedir( self, # type: T path, # type: Text permissions=None, # type: Optional[Permissions] recreate=False, # type: bool ): # type: (...) -> SubFS[T] self.check() raise errors.ResourceReadOnly(path) def openbin(self, path, mode="r", buffering=-1, **options): # type: (Text, Text, int, **Any) -> BinaryIO _path = relpath(self.validatepath(path)) if "w" in mode or "+" in mode or "a" in mode: raise errors.ResourceReadOnly(path) try: member = self._tar.getmember(self._encode(_path)) except KeyError: six.raise_from(errors.ResourceNotFound(path), None) if not member.isfile(): raise errors.FileExpected(path) rw = RawWrapper(cast(IO, self._tar.extractfile(member))) if six.PY2: # Patch nonexistent file.flush in Python2 def _flush(): pass rw.flush = _flush return rw # type: ignore def remove(self, path): # type: (Text) -> None self.check() raise errors.ResourceReadOnly(path) def removedir(self, path): # type: (Text) -> None self.check() raise errors.ResourceReadOnly(path) def close(self): # type: () -> None super(ReadTarFS, self).close() self._tar.close() def isclosed(self): # type: () -> bool return self._tar.closed # type: ignore
if __name__ == "__main__": # pragma: no cover from fs.tree import render from fs.opener import open_fs with TarFS("tests.tar") as tar_fs: print(tar_fs.listdir("/")) print(tar_fs.listdir("/tests/")) print(tar_fs.readtext("tests/ttt/settings.ini")) render(tar_fs) print(tar_fs) print(repr(tar_fs)) with TarFS("TarFS.tar", write=True) as tar_fs: tar_fs.makedirs("foo/bar") tar_fs.writetext("foo/bar/baz.txt", "Hello, World") print(tar_fs) print(repr(tar_fs))