Establish a canonical JSON representation for NeXus metadata

[paulmillar]

The NeXus metadata model is abstract. Although it is mostly commonly mapped to HDF5, it can also be mapped to XML. Given the recent (and on-going) work on mapping NeXus definitions to a corresponding ontology, it should also be possible to map NeXus metadata to corresponding statements within that ontology.

JSON is now a well-established format for recording information. There are a number of foundational technologies that work with JSON data, such as schemas, information extraction and manipulation. There are also many storage technologies that provide enhanced support for data in JSON format.

It would be helpful if NIAC established a mapping of NeXus metadata to JSON.

Possible use-cases include:

• storing NeXus metadata separately from the HDF5, in databases optimised for querying
• allowing network-transparent dataset querying using technologies that support JSON-backed information model.
• deliver metadata independently of the data, to allow software to investigate possible datasets of interest without downloading complete HDF5 files.
• support technologies that build summary information, based on JSON information models.

Having NIAC establish a canonical mapping of NeXus to JSON would avoid duplicated effort.