codekingpro/portable-devtools

1import base642import io3from urllib.parse import unquote4 5from fsspec import AbstractFileSystem6 7 8class DataFileSystem(AbstractFileSystem):9    """A handy decoder for data-URLs10 11    Example12    -------13    >>> with fsspec.open("data:,Hello%2C%20World%21") as f:14    ...     print(f.read())15    b"Hello, World!"16 17    See https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/Data_URLs18    """19 20    protocol = "data"21 22    def __init__(self, **kwargs):23        """No parameters for this filesystem"""24        super().__init__(**kwargs)25 26    def cat_file(self, path, start=None, end=None, **kwargs):27        pref, data = path.split(",", 1)28        if pref.endswith("base64"):29            return base64.b64decode(data)[start:end]30        return unquote(data).encode()[start:end]31 32    def info(self, path, **kwargs):33        pref, name = path.split(",", 1)34        data = self.cat_file(path)35        mime = pref.split(":", 1)[1].split(";", 1)[0]36        return {"name": name, "size": len(data), "type": "file", "mimetype": mime}37 38    def _open(39        self,40        path,41        mode="rb",42        block_size=None,43        autocommit=True,44        cache_options=None,45        **kwargs,46    ):47        if "r" not in mode:48            raise ValueError("Read only filesystem")49        return io.BytesIO(self.cat_file(path))50 51    @staticmethod52    def encode(data: bytes, mime: str | None = None):53        """Format the given data into data-URL syntax54 55        This version always base64 encodes, even when the data is ascii/url-safe.56        """57        return f"data:{mime or ''};base64,{base64.b64encode(data).decode()}"58