HAL or JSON-LD ?

[MarcBruyland]

A remark came from one of the participants of the ICEG training on 2022-06-13:

"GCloudBE defines a JSON structuring format based on HAL, whereas you seem to be using JSON-LD as a base for your standar.
How do you see these standards;does JSON-LD supersede GCloud, should we do both, or does it depend on context (and when should we be using which)?"

Reaction:

The REST styleguide mentions:
The use of Web Linking and Hypertext Application Language (HAL) is not recommended.

Note that the REST styleguide is not focusing on semantic interoperability, contrary to the ICEG data standards which are focusing on semantics.
You will not find anything on JSON-LD (which is recommended in the ICEG training) in the REST styleguide.
The reason why this phrase is put in the REST styleguide is that HAL was considered to be too complex.
Under the representatives of the G-Cloud work groups nobody heard of a recommendation to use HAL (if you have more info, pls let us know).

What you can find in the REST styleguide regarding the usage of hyperlinks:
https://www.belgif.be/specification/rest/api-guide/#pagination
https://www.belgif.be/specification/rest/api-guide/#hypermedia-controls

[barthanssens]

Except that the REST styleguide is actually using some parts of HAL... (self/href/embedded, though without underscore...)
It might be possible to bolt JSON-LD onto the Belgif/Gcloud REST structure, though it might not look pretty.

Also note that for JSON-LD, hypermedia controls are more likely to be implemented with Hydra (http://www.hydra-cg.com/spec/latest/core/). Again some mapping might be possible (hydra:next to next, for example)

[wsalembi]

The styleguide doesn't promote HAL or LD-JSON. Our hyperlinking guidelines are much simplified and defined by the REST standard workgroup. These guidelines might reuse some obvious terminology also used in HAL, without the intention to follow that 'standard'. HAL was invented by a single consultant and never left the DRAFT status.