co-existence of multiple query languages

[Sakurann]

I think we should have an idea how the co-existence of or transition between two query languages in OpenID4Vp will happen: PE v2 and a new one.

Is one or the other mandatory? for whom? How does the wallet know which query language it is receiving? does this mean we should define a different high level parameter that is not presentation_definition for a new query language?

[Sakurann]

discussed in a WG.

• there seems to be an agreement to use a different top -level parameter for a new query language. @jogu proposed vp_query, but we should bikeshed.
  • there was a proposal to have a top-level parameter under which query language specific parameters sit (would break existing PE implementations and we hopefully/probably won't have more than 2 query languages...) - leaning towards keeping it simple and not defining such an extension.

[bc-pi]

presentation_definition is a... um... silly name at best so no need to keep that

[selfissued]

I agree that the new query language should use its own parameter names.

[David-Chadwick]

I prefer a top level parameter called something like "query-language" and then beneath this there will be the query languages that we support - currently only two, but who knows what else in future? Remember that until a few months ago we only mandated one query language, now we support two. This proposed structure is future proof so that if we want to add a third in future the structure of the current two will not change.