TypeError: Expected a BytesBytesCodec. Got <class 'numcodecs.blosc.Blosc'> instead.

[leoniewgnr]

This code runs without any problems with zarr2, but give the following error when running with zarr3:

import pandas as pd
import numpy as np
import xarray as xr
from numcodecs.blosc import Blosc

ds = xr.Dataset(
    {"foo": (("x", "y"), np.random.rand(4, 5))},
    coords={
        "x": [10, 20, 30, 40],
        "y": pd.date_range("2000-01-01", periods=5),
        "z": ("x", list("abcd")),
    },
)

tmp_path = 'tmp.zarr'

# this works
ds.to_zarr(tmp_path, mode="w")
print('Saved to tmp.zarr')

# this does not work 
compressor = Blosc(cname="zstd", clevel=3, shuffle=2)
ds.to_zarr(tmp_path, encoding={"foo": {"compressor": compressor}}, mode="w")
print('Saved to tmp.zarr')

The error message is: TypeError: Expected a BytesBytesCodec. Got <class 'numcodecs.blosc.Blosc'> instead.
The same error occurs in the documentation: https://docs.xarray.dev/en/stable/user-guide/io.html#zarr-compressors-and-filters

[welcome]

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[TomNicholas]

Thanks for raising this @leoniewgnr ! We're still hunting down all the bugs that the move to zarr 3 created.

The same error occurs in the documentation:

That's particularly weird - errors in the documentation examples are supposed to lead to errors in the CI...

[keewis]

See also #9987