polytropos-openapi3

Automatic OpenAPI 3.0 specification and JSON Schema generation for polytropos open records and variants via openapi3.

Overview

polytropos-openapi3 synthesizes ToSchema instances for open records and variants:

• Open records generate object schemas with typed properties and required field lists.
• Open variants generate oneOf tagged-union schemas with discriminator objects.

Features

• No Generics Blowup: Direct type-level row inspection without generic binary tree expansion.
• Full OpenAPI 3.0 Compliance: Emits schemas directly consumed by Swagger UI, Redoc, and OpenAPI code generators.
• Customizable Schemas: Combine with custom descriptions, examples, and formats.

Quick Example

{-# LANGUAGE DataKinds #-}
{-# LANGUAGE TypeApplications #-}
{-# OPTIONS_GHC -fplugin=Polytropos.Plugin #-}

import Data.OpenApi (toSchema, Schema)
import Data.Proxy (Proxy (..))
import Polytropos
import Polytropos.OpenApi

type User = Record '["id" ':= Int, "name" ':= String]

user :: User
user = REC { id = 1, name = "Alice" }

-- Generate OpenAPI 3.0 schema directly from the row specification
userSchema :: Schema
userSchema = toSchema (Proxy @User)

License

Dual-licensed under EUPL-1.2 OR Apache-2.0.