Unless I’m missing something, the response schema will have an optional “comments” field whether the “with_comments” arg is passed or not.
Graphql works the same way if i'm not mistaken.
and if its the case that you don't want the comments at all, then in the conditionals write your sql statements
if you want comments
select * from resource where id=some resource id
if you don't
select without comments from resource where id=some resource id
there's no need to get into specifics, the point is graphql is not bringing anything novel. everything it claims to do can be implemented in RESt if you're willing to implement it.
With a REST API, the “resource” type will always have an optional “comments” field, whatever the value of arg is.
With a GraphQL API you’ll have the right type depending on your query.
In general, the tooling/spec has thousands of open bugs, isnt going anywhere, moves very slowly and is missing fundamental features.
https://github.com/OAI/OpenAPI-Specification/issues/1998 heres the ticket where it will inevitably be ignored and die. But even if it was supported in the spec, the open source generators wont support it anyways.
Said generators also uses "logic less" templates to generate something that very much needs logic. As a FE dev, I love nothing more than to fork a an archaic Java based generator to get the client gen working...not.
So if you wanted comments you would send a request with a header like "Accept: application/resource_with_comments", and you'd send a Header like "Accept: application/resource_without_comments".
The thing is, few people want this level of control in practice. This would generally lead to a huge proliferation of types for very little practical benefit. Much simpler to have a set of well-defined types with optional fields than to define a new type for each combination of fields used today.