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GHC 10.0.0.20260917 · lts/ghc-10.0.x · 8fef28d · 2026-11-02

classclass HasOpenApi (api :: k) where

Generate a OpenApi specification for a servant API.

To generate OpenApi specification, your data types need ToParamSchema and/or ToSchema instances.

ToParamSchema is used for Capture, QueryParam and Header. ToSchema is used for ReqBody and response data types.

You can easily derive those instances via Generic. For more information, refer to openapi3 documentation.

Example:

newtype Username = Username String deriving (Generic, ToText)

instance ToParamSchema Username

data User = User
  { username :: Username
  , fullname :: String
  } deriving (Generic)

instance ToJSON User
instance ToSchema User

type MyAPI = QueryParam "username" Username :> Get '[JSON] User

myOpenApi :: OpenApi
myOpenApi = toOpenApi (Proxy :: Proxy MyAPI)

Methods

Instances32HasOpenApi, …
classclass OpenApiMethod (method :: k) where

Methods, available for OpenApi.

Methods

Instances7OpenApiMethod, …
classclass IsSwaggerResponse (a :: k) where
#
Instances4IsSwaggerResponse

Orphan instances

1 instance