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tags: draft, issues
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# B-Open Deliverable 2 Issue
Original tweet: https://twitter.com/rabernat/status/1380205129509523457
Deliverable 2: _ARRAY_DIMENSIONS convention
The Xarray community has defined as specified in http://xarray.pydata.org/en/stable/internals/zarr-encoding-spec.html the Zarr metadata key “_ARRAY_DIMENSIONS” for storing additional information needed by Xarray to open a collection of Zarr arrays. An ongoing discussion with the NetCDF community (https://github.com/zarr-developers/zarr-specs/issues/73) points to the need to unify this convention. This is also critical for supporting the Xarray API from OME-Zarr, for which some steps have already been taken (https://github.com/ome/ngff/issues/48).
Tasks:
Submit convention to the central registry
Update V2 spec as necessary based on public discussions
If necessary, add support for NetCDF-specified metadata patterns in Xarray
Review behavior in Xarray if the metadata is missing
Test the various metadata states in ome-zarr-py as well as aicsimageio
Unidata supports
Add support for nczarr to xarray