json-ntv 1.0.0

JSON-NTV a semantic format for interoperability

JSON-NTV (named and typed value) : a semantic format for interoperability

JSON-NTV is a universal representation format. It allows the sharing and conversion of any type of data (NTV format).

The NTV format is part of the Environmental Sensing Project

NTV

Today, the semantic level of shared data remains low. It is very often limited to the type of data defined in the exchange formats (strings for CSV formats; numbers, strings, arrays and objects for JSON formats).

The proposed consists of adding a type and a name to the data exchanged (see also the presentation documents and examples.

With this evolution any data, whatever its semantic level, can be identified, shared and interpreted in a consistent way. The implementation of a type with a nested structure facilitates its appropriation. Finally, compatibility with existing JSON structures allows progressive deployment.

NTV uses

Several variations and use cases of the NTV format are defined:

• Tabular data exchange format (e.g. open-data)
• Compact, reversible and semantic pandas - JSON interface
• Comment and change management of JSON data
• Mermaid visualization of JSON tree
• JSON data editor

NTV structure

The constructed entities (called NTV for named typed value) are therefore a triplet with one mandatory element (the value in JSON format) and two optional elements (name, type).

For example, the location of Paris can be represented by:

• a name: "Paris",
• a type: the coordinates of a point according to the GeoJSON format,
• a value: [ 2.3522, 48.8566]

The easiest way to add this information into a JSON-value is to use a JSON-object with a single member using the syntax JSON-ND for the first term of the member and the JSON-value for the second term of the member.

For the example above, the JSON representation is:
{ "paris:point" : [2.3522, 48.8566] }

With this approach, two NTV entities are defined:

• a primitive entity which is not composed of any other entity (NTV-single),
• a structured entity which is an ordered sequence of NTV entities (NTV-list).

as well as two JSON formats:

• simple format when the name and the type are not present (this is the usual case of CSV data),
• named format when the name or type is present (see example above for an NTV-single entity and below for a structured entity).

Example of an entity composed of two other entities:

• { "cities::point": [[2.3522, 48.8566], [4.8357, 45.7640]] } for an unnamed NTV-list entity
• { "cities::point": { "paris":[2.3522, 48.8566], "lyon":[4.8357, 45.7640] } } for a named NTV-list entity

Note: This syntax can also be used for CSV file headers

The type incorporates a notion of namespaces that can be nested.

For example, the type: "ns1.ns2.type" means that:

• ns1. is a namespace defined in the global namespace,
• ns2. is a namespace defined in the ns1 namespace.,
• type is defined in the ns2 namespace.

This structuring of type makes it possible to reference any type of data that has a JSON representation and to consolidate all the shared data structures within the same tree of types.

NTV and JSON

The flowchart below explain how to convert and exchange native entities through NTV and JSON format.

flowchart LR
    text["#10240;#10240;JSON#10240;#10240;\ntext"]
    val["#10240;JSON-NTV#10240;\nvalue"]
    ntv["#10240;#10240;#10240;NTV#10240;#10240;#10240;\nentity"]
    nat["#10240;native#10240;\nentity"]
    text--->|JSON load|val
    val--->|JSON dump|text
    val--->|NTV from JSON|ntv
    ntv--->|from NTV|nat
    ntv--->|NTV to JSON|val
    nat--->|to NTV|ntv

Properties :

• each NTV object has a unique JSON representation
• each JSON data corresponds to a unique NTV entity
• an NTV entity is a tree where each node is an NTV entity and each leaf an NTV-Single entity
• an NTV entity is a neutral representation (independent of a software or hardware platform)

Documentation and installation

• Specification
• Example
• Python Connectors documentation
• installation and package

If you are interested challenge us ! We will be very happy to show you the relevance of our approach