import io import posixpath import zipfile import itertools import contextlib import pathlib from .py310compat import text_encoding __all__ = ['Path'] def _parents(path): """ Given a path with elements separated by posixpath.sep, generate all parents of that path. >>> list(_parents('b/d')) ['b'] >>> list(_parents('/b/d/')) ['/b'] >>> list(_parents('b/d/f/')) ['b/d', 'b'] >>> list(_parents('b')) [] >>> list(_parents('')) [] """ return itertools.islice(_ancestry(path), 1, None) def _ancestry(path): """ Given a path with elements separated by posixpath.sep, generate all elements of that path >>> list(_ancestry('b/d')) ['b/d', 'b'] >>> list(_ancestry('/b/d/')) ['/b/d', '/b'] >>> list(_ancestry('b/d/f/')) ['b/d/f', 'b/d', 'b'] >>> list(_ancestry('b')) ['b'] >>> list(_ancestry('')) [] """ path = path.rstrip(posixpath.sep) while path and path != posixpath.sep: yield path path, tail = posixpath.split(path) _dedupe = dict.fromkeys """Deduplicate an iterable in original order""" def _difference(minuend, subtrahend): """ Return items in minuend not in subtrahend, retaining order with O(1) lookup. """ return itertools.filterfalse(set(subtrahend).__contains__, minuend) class InitializedState: """ Mix-in to save the initialization state for pickling. """ def __init__(self, *args, **kwargs): self.__args = args self.__kwargs = kwargs super().__init__(*args, **kwargs) def __getstate__(self): return self.__args, self.__kwargs def __setstate__(self, state): args, kwargs = state super().__init__(*args, **kwargs) class CompleteDirs(InitializedState, zipfile.ZipFile): """ A ZipFile subclass that ensures that implied directories are always included in the namelist. """ @staticmethod def _implied_dirs(names): parents = itertools.chain.from_iterable(map(_parents, names)) as_dirs = (p + posixpath.sep for p in parents) return _dedupe(_difference(as_dirs, names)) def namelist(self): names = super(CompleteDirs, self).namelist() return names + list(self._implied_dirs(names)) def _name_set(self): return set(self.namelist()) def resolve_dir(self, name): """ If the name represents a directory, return that name as a directory (with the trailing slash). """ names = self._name_set() dirname = name + '/' dir_match = name not in names and dirname in names return dirname if dir_match else name @classmethod def make(cls, source): """ Given a source (filename or zipfile), return an appropriate CompleteDirs subclass. """ if isinstance(source, CompleteDirs): return source if not isinstance(source, zipfile.ZipFile): return cls(source) # Only allow for FastLookup when supplied zipfile is read-only if 'r' not in source.mode: cls = CompleteDirs source.__class__ = cls return source class FastLookup(CompleteDirs): """ ZipFile subclass to ensure implicit dirs exist and are resolved rapidly. """ def namelist(self): with contextlib.suppress(AttributeError): return self.__names self.__names = super(FastLookup, self).namelist() return self.__names def _name_set(self): with contextlib.suppress(AttributeError): return self.__lookup self.__lookup = super(FastLookup, self)._name_set() return self.__lookup class Path: """ A pathlib-compatible interface for zip files. Consider a zip file with this structure:: . ├── a.txt └── b ├── c.txt └── d └── e.txt >>> data = io.BytesIO() >>> zf = zipfile.ZipFile(data, 'w') >>> zf.writestr('a.txt', 'content of a') >>> zf.writestr('b/c.txt', 'content of c') >>> zf.writestr('b/d/e.txt', 'content of e') >>> zf.filename = 'mem/abcde.zip' Path accepts the zipfile object itself or a filename >>> root = Path(zf) From there, several path operations are available. Directory iteration (including the zip file itself): >>> a, b = root.iterdir() >>> a Path('mem/abcde.zip', 'a.txt') >>> b Path('mem/abcde.zip', 'b/') name property: >>> b.name 'b' join with divide operator: >>> c = b / 'c.txt' >>> c Path('mem/abcde.zip', 'b/c.txt') >>> c.name 'c.txt' Read text: >>> c.read_text() 'content of c' existence: >>> c.exists() True >>> (b / 'missing.txt').exists() False Coercion to string: >>> import os >>> str(c).replace(os.sep, posixpath.sep) 'mem/abcde.zip/b/c.txt' At the root, ``name``, ``filename``, and ``parent`` resolve to the zipfile. Note these attributes are not valid and will raise a ``ValueError`` if the zipfile has no filename. >>> root.name 'abcde.zip' >>> str(root.filename).replace(os.sep, posixpath.sep) 'mem/abcde.zip' >>> str(root.parent) 'mem' """ __repr = "{self.__class__.__name__}({self.root.filename!r}, {self.at!r})" def __init__(self, root, at=""): """ Construct a Path from a ZipFile or filename. Note: When the source is an existing ZipFile object, its type (__class__) will be mutated to a specialized type. If the caller wishes to retain the original type, the caller should either create a separate ZipFile object or pass a filename. """ self.root = FastLookup.make(root) self.at = at def open(self, mode='r', *args, pwd=None, **kwargs): """ Open this entry as text or binary following the semantics of ``pathlib.Path.open()`` by passing arguments through to io.TextIOWrapper(). """ if self.is_dir(): raise IsADirectoryError(self) zip_mode = mode[0] if not self.exists() and zip_mode == 'r': raise FileNotFoundError(self) stream = self.root.open(self.at, zip_mode, pwd=pwd) if 'b' in mode: if args or kwargs: raise ValueError("encoding args invalid for binary operation") return stream else: kwargs["encoding"] = text_encoding(kwargs.get("encoding")) return io.TextIOWrapper(stream, *args, **kwargs) @property def name(self): return pathlib.Path(self.at).name or self.filename.name @property def suffix(self): return pathlib.Path(self.at).suffix or self.filename.suffix @property def suffixes(self): return pathlib.Path(self.at).suffixes or self.filename.suffixes @property def stem(self): return pathlib.Path(self.at).stem or self.filename.stem @property def filename(self): return pathlib.Path(self.root.filename).joinpath(self.at) def read_text(self, *args, **kwargs): kwargs["encoding"] = text_encoding(kwargs.get("encoding")) with self.open('r', *args, **kwargs) as strm: return strm.read() def read_bytes(self): with self.open('rb') as strm: return strm.read() def _is_child(self, path): return posixpath.dirname(path.at.rstrip("/")) == self.at.rstrip("/") def _next(self, at): return self.__class__(self.root, at) def is_dir(self): return not self.at or self.at.endswith("/") def is_file(self): return self.exists() and not self.is_dir() def exists(self): return self.at in self.root._name_set() def iterdir(self): if not self.is_dir(): raise ValueError("Can't listdir a file") subs = map(self._next, self.root.namelist()) return filter(self._is_child, subs) def __str__(self): return posixpath.join(self.root.filename, self.at) def __repr__(self): return self.__repr.format(self=self) def joinpath(self, *other): next = posixpath.join(self.at, *other) return self._next(self.root.resolve_dir(next)) __truediv__ = joinpath @property def parent(self): if not self.at: return self.filename.parent parent_at = posixpath.dirname(self.at.rstrip('/')) if parent_at: parent_at += '/' return self._next(parent_at)