structure saas with tools

.venv/lib/python3.10/site-packages/fsspec/implementations/cache_mapper.py

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+from __future__ import annotations
+
+import abc
+import hashlib
+
+from fsspec.implementations.local import make_path_posix
+
+
+class AbstractCacheMapper(abc.ABC):
+    """Abstract super-class for mappers from remote URLs to local cached
+    basenames.
+    """
+
+    @abc.abstractmethod
+    def __call__(self, path: str) -> str: ...
+
+    def __eq__(self, other: object) -> bool:
+        # Identity only depends on class. When derived classes have attributes
+        # they will need to be included.
+        return isinstance(other, type(self))
+
+    def __hash__(self) -> int:
+        # Identity only depends on class. When derived classes have attributes
+        # they will need to be included.
+        return hash(type(self))
+
+
+class BasenameCacheMapper(AbstractCacheMapper):
+    """Cache mapper that uses the basename of the remote URL and a fixed number
+    of directory levels above this.
+
+    The default is zero directory levels, meaning different paths with the same
+    basename will have the same cached basename.
+    """
+
+    def __init__(self, directory_levels: int = 0):
+        if directory_levels < 0:
+            raise ValueError(
+                "BasenameCacheMapper requires zero or positive directory_levels"
+            )
+        self.directory_levels = directory_levels
+
+        # Separator for directories when encoded as strings.
+        self._separator = "_@_"
+
+    def __call__(self, path: str) -> str:
+        path = make_path_posix(path)
+        prefix, *bits = path.rsplit("/", self.directory_levels + 1)
+        if bits:
+            return self._separator.join(bits)
+        else:
+            return prefix  # No separator found, simple filename
+
+    def __eq__(self, other: object) -> bool:
+        return super().__eq__(other) and self.directory_levels == other.directory_levels
+
+    def __hash__(self) -> int:
+        return super().__hash__() ^ hash(self.directory_levels)
+
+
+class HashCacheMapper(AbstractCacheMapper):
+    """Cache mapper that uses a hash of the remote URL."""
+
+    def __call__(self, path: str) -> str:
+        return hashlib.sha256(path.encode()).hexdigest()
+
+
+def create_cache_mapper(same_names: bool) -> AbstractCacheMapper:
+    """Factory method to create cache mapper for backward compatibility with
+    ``CachingFileSystem`` constructor using ``same_names`` kwarg.
+    """
+    if same_names:
+        return BasenameCacheMapper()
+    else:
+        return HashCacheMapper()