This implements an initial set of DTO types that represent serialized metadata. These new types come with codecs using autodocodec which are used to derive both JSON serialization, and OpenAPI documentation. This ensures that we can automatically generate API documentation that is guaranteed to match JSON produced by the server.
For the moment the new types are not used for anything except to generate an early version of an OpenAPI document. Because this is early work the DTO types for each metadata format version list top-level properties only with placeholders for the types of each top-level property. This early iteration demonstrates using a sum type in Haskell that maps to a tagged union in OpenAPI (using the `version` field value as a tag).
This work is experimental and incomplete! Please do not incorporate the generated OpenAPI documentation into essential workflows at this time.
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/4801
GitOrigin-RevId: d2f110a6237b73520cdba24667333ef14e8cdd3d
