response.ml

(*----------------------------------------------------------------------------
 *  Copyright (c) 2019 António Nuno Monteiro
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module Response = Piaf.Response
module StringSet = Set.Make (String)

module Headers = struct
  include Piaf.Headers

  let to_yojson headers =
    let keys = StringSet.of_list (List.map fst (to_list headers)) in
    `Assoc
      (StringSet.fold
         (fun name acc ->
           let element =
             match get_multi headers name with
             | [ x ] -> name, `String x
             | xs -> name, `List (List.map (fun v -> `String v) xs)
           in
           element :: acc)
         keys
         [])
end

type vercel_proxy_response =
  { status_code : int [@key "statusCode"]
  ; headers : Headers.t
  ; body : string
  ; encoding : string option
  }
[@@deriving to_yojson]

type t = Response.t

let to_yojson { Response.status; headers; body; _ } =
  let body = Result.get_ok (Piaf.Body.to_string body) in
  let vercel_proxy_response =
    { status_code = Piaf.Status.to_code status; headers; body; encoding = None }
  in
  vercel_proxy_response_to_yojson vercel_proxy_response