WOT TD round tripping for securityDefinitions

[Murloc6]

We attacked the WOT security round-tripping problem under a new angle than #1125.

If we use this specific TD as input:

{
  "@context": {
    "td": "https://www.w3.org/2019/wot/td#",
    "security": {
      "@id": "td:hasSecurityConfiguration",
      "@type": "@id"
    },
    "securityDefinitions": {
      "@id": "td:securityDefinitions",
      "@type": "@id",
      "@container": "@index",
      "@context": {
        "scheme": {
          "@id": "rdf:type",
          "@type": "@vocab"
        }
      }
    }
  },
  "@id": "toto",
  "@type": "td:Thing",
  "security": [
    "basic_sc"
  ],
  "securityDefinitions": {
    "basic_sc": {
      "scheme": "basic"
    }
  }
}

With the current context, we obtain the following RDF triples playground.
The "basic_sc" information from the "securityDefinitions" is lost.

If we try to frame this example with the current context, we obtain the following json-ld playground.
The "basic_sc" key on "securityDefinitions" is lost.

We first thought about using the same URI for "basic_sc" in "security" and "securityDefinitions" (c.f. #1167) however this case cannot be easily framed in json-ld because the same object is used in various fields. For example, here playground, we used "@container":"@id" for securityDefinitions so that the "basic_sc" URI is used in both RDF triples (securityDefinitions and hasSecurityConfiguration). However, when framing it (c.f. playground), the securityDefinitions information are moved to the security field.

The most satisfying solution we found is to define a new relation between the security definition node and the security configuration URI. Here we propose to use the relation "td:securityDefinitionForSecurityConfiguration" between them. playground.
As you may see here, there is a new triple:

_:b0 <https://www.w3.org/2019/wot/td#securityDefinitionForSecurityConfiguration> <https://json-ld.org/playground/basic_sc> .

which links both nodes.
Once framing it back with the same context, (c.f. playground) the round-tripping works fine.

This solution requires the defintion of a new property in one of the TD vocabularies (in this example we called it "securityDefinitionForSecurityConfiguration"). However, we do not know if this property is compliant with your ontology.