numcodecs warn on read #3832
Description
I think it's not very good user experience to spam with warnings when reading a non-spec codec e.g. from numcodecs. The warning on write makes sense, but currently there is no way for an end user to read a numcodecs store without warnings.
import warnings
import zarr
from zarr.codecs import numcodecs
warnings.simplefilter("always")
# Warns on both write and read
a = zarr.create_array({}, shape=(10,), chunks=(10,), dtype="uint8", compressors=[numcodecs.Zstd(level=1)])
zarr.open_array(a.store, mode="r")