Queries with zarr v3

[clbarnes]

Core protocol

• Store-specific implementation details (e.g. separator, metadata extension) need to be known by the caller - isn't the point to make a canonical URL that the Store can interpret how it wants?
• If compressor could describe any codec (not necessarily one which compresses/decompresses data), should the top key be "codec" instead?
• When should an error be returned when encountering an unknown must_understand extension in an array -- when decoding the metadata, or when performing chunk IO?
• Why do most core data types use byte counts but r types use multiple of 8 bit counts?
• Do implicit groups have implicit attributes?

File System

• Metadata in separate tree to actual data makes it harder to use standard file system tools (cp, ln, rm -r)
  • File system store could mangle the path to put the metadata in the same directory