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Diffstat (limited to '.venv/lib/python3.12/site-packages/fsspec/mapping.py')
| -rw-r--r-- | .venv/lib/python3.12/site-packages/fsspec/mapping.py | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/fsspec/mapping.py b/.venv/lib/python3.12/site-packages/fsspec/mapping.py new file mode 100644 index 00000000..752eef35 --- /dev/null +++ b/.venv/lib/python3.12/site-packages/fsspec/mapping.py @@ -0,0 +1,251 @@ +import array +import logging +import posixpath +import warnings +from collections.abc import MutableMapping +from functools import cached_property + +from fsspec.core import url_to_fs + +logger = logging.getLogger("fsspec.mapping") + + +class FSMap(MutableMapping): + """Wrap a FileSystem instance as a mutable wrapping. + + The keys of the mapping become files under the given root, and the + values (which must be bytes) the contents of those files. + + Parameters + ---------- + root: string + prefix for all the files + fs: FileSystem instance + check: bool (=True) + performs a touch at the location, to check for write access. + + Examples + -------- + >>> fs = FileSystem(**parameters) # doctest: +SKIP + >>> d = FSMap('my-data/path/', fs) # doctest: +SKIP + or, more likely + >>> d = fs.get_mapper('my-data/path/') + + >>> d['loc1'] = b'Hello World' # doctest: +SKIP + >>> list(d.keys()) # doctest: +SKIP + ['loc1'] + >>> d['loc1'] # doctest: +SKIP + b'Hello World' + """ + + def __init__(self, root, fs, check=False, create=False, missing_exceptions=None): + self.fs = fs + self.root = fs._strip_protocol(root) + self._root_key_to_str = fs._strip_protocol(posixpath.join(root, "x"))[:-1] + if missing_exceptions is None: + missing_exceptions = ( + FileNotFoundError, + IsADirectoryError, + NotADirectoryError, + ) + self.missing_exceptions = missing_exceptions + self.check = check + self.create = create + if create: + if not self.fs.exists(root): + self.fs.mkdir(root) + if check: + if not self.fs.exists(root): + raise ValueError( + f"Path {root} does not exist. Create " + f" with the ``create=True`` keyword" + ) + self.fs.touch(root + "/a") + self.fs.rm(root + "/a") + + @cached_property + def dirfs(self): + """dirfs instance that can be used with the same keys as the mapper""" + from .implementations.dirfs import DirFileSystem + + return DirFileSystem(path=self._root_key_to_str, fs=self.fs) + + def clear(self): + """Remove all keys below root - empties out mapping""" + logger.info("Clear mapping at %s", self.root) + try: + self.fs.rm(self.root, True) + self.fs.mkdir(self.root) + except: # noqa: E722 + pass + + def getitems(self, keys, on_error="raise"): + """Fetch multiple items from the store + + If the backend is async-able, this might proceed concurrently + + Parameters + ---------- + keys: list(str) + They keys to be fetched + on_error : "raise", "omit", "return" + If raise, an underlying exception will be raised (converted to KeyError + if the type is in self.missing_exceptions); if omit, keys with exception + will simply not be included in the output; if "return", all keys are + included in the output, but the value will be bytes or an exception + instance. + + Returns + ------- + dict(key, bytes|exception) + """ + keys2 = [self._key_to_str(k) for k in keys] + oe = on_error if on_error == "raise" else "return" + try: + out = self.fs.cat(keys2, on_error=oe) + if isinstance(out, bytes): + out = {keys2[0]: out} + except self.missing_exceptions as e: + raise KeyError from e + out = { + k: (KeyError() if isinstance(v, self.missing_exceptions) else v) + for k, v in out.items() + } + return { + key: out[k2] if on_error == "raise" else out.get(k2, KeyError(k2)) + for key, k2 in zip(keys, keys2) + if on_error == "return" or not isinstance(out[k2], BaseException) + } + + def setitems(self, values_dict): + """Set the values of multiple items in the store + + Parameters + ---------- + values_dict: dict(str, bytes) + """ + values = {self._key_to_str(k): maybe_convert(v) for k, v in values_dict.items()} + self.fs.pipe(values) + + def delitems(self, keys): + """Remove multiple keys from the store""" + self.fs.rm([self._key_to_str(k) for k in keys]) + + def _key_to_str(self, key): + """Generate full path for the key""" + if not isinstance(key, str): + # raise TypeError("key must be of type `str`, got `{type(key).__name__}`" + warnings.warn( + "from fsspec 2023.5 onward FSMap non-str keys will raise TypeError", + DeprecationWarning, + ) + if isinstance(key, list): + key = tuple(key) + key = str(key) + return f"{self._root_key_to_str}{key}".rstrip("/") + + def _str_to_key(self, s): + """Strip path of to leave key name""" + return s[len(self.root) :].lstrip("/") + + def __getitem__(self, key, default=None): + """Retrieve data""" + k = self._key_to_str(key) + try: + result = self.fs.cat(k) + except self.missing_exceptions as exc: + if default is not None: + return default + raise KeyError(key) from exc + return result + + def pop(self, key, default=None): + """Pop data""" + result = self.__getitem__(key, default) + try: + del self[key] + except KeyError: + pass + return result + + def __setitem__(self, key, value): + """Store value in key""" + key = self._key_to_str(key) + self.fs.mkdirs(self.fs._parent(key), exist_ok=True) + self.fs.pipe_file(key, maybe_convert(value)) + + def __iter__(self): + return (self._str_to_key(x) for x in self.fs.find(self.root)) + + def __len__(self): + return len(self.fs.find(self.root)) + + def __delitem__(self, key): + """Remove key""" + try: + self.fs.rm(self._key_to_str(key)) + except Exception as exc: + raise KeyError from exc + + def __contains__(self, key): + """Does key exist in mapping?""" + path = self._key_to_str(key) + return self.fs.isfile(path) + + def __reduce__(self): + return FSMap, (self.root, self.fs, False, False, self.missing_exceptions) + + +def maybe_convert(value): + if isinstance(value, array.array) or hasattr(value, "__array__"): + # bytes-like things + if hasattr(value, "dtype") and value.dtype.kind in "Mm": + # The buffer interface doesn't support datetime64/timdelta64 numpy + # arrays + value = value.view("int64") + value = bytes(memoryview(value)) + return value + + +def get_mapper( + url="", + check=False, + create=False, + missing_exceptions=None, + alternate_root=None, + **kwargs, +): + """Create key-value interface for given URL and options + + The URL will be of the form "protocol://location" and point to the root + of the mapper required. All keys will be file-names below this location, + and their values the contents of each key. + + Also accepts compound URLs like zip::s3://bucket/file.zip , see ``fsspec.open``. + + Parameters + ---------- + url: str + Root URL of mapping + check: bool + Whether to attempt to read from the location before instantiation, to + check that the mapping does exist + create: bool + Whether to make the directory corresponding to the root before + instantiating + missing_exceptions: None or tuple + If given, these exception types will be regarded as missing keys and + return KeyError when trying to read data. By default, you get + (FileNotFoundError, IsADirectoryError, NotADirectoryError) + alternate_root: None or str + In cases of complex URLs, the parser may fail to pick the correct part + for the mapper root, so this arg can override + + Returns + ------- + ``FSMap`` instance, the dict-like key-value store. + """ + # Removing protocol here - could defer to each open() on the backend + fs, urlpath = url_to_fs(url, **kwargs) + root = alternate_root if alternate_root is not None else urlpath + return FSMap(root, fs, check, create, missing_exceptions=missing_exceptions) |