(* TODO
   GNU Taler db-events
   https://git.gnunet.org/gana.git/tree/gnu-taler-db-events/registry.rec *)

let test req server _ =
  let pool = Vif.Server.device Devices.caqti server in
  let query =
    let open Caqti_request.Infix in
    Caqti_type.(unit ->! int) "SELECT 53 - 11"
  in
  let fn (module Conn : Caqti_miou.CONNECTION) = Conn.find query () in
  match Caqti_miou_unix.Pool.use fn pool with
  | Ok n ->
      let open Vif.Response.Syntax in
      let* () =
        Vif.Response.add ~field:"content-type" "text/plain; charset= utf-8"
      in
      let* () = Vif.Response.with_string req (Fmt.str "53 - 11 = %d@." n) in
      Vif.Response.respond `OK
  | Error err ->
      (* TODO don't leak private data in error messages *)
      let open Vif.Response.Syntax in
      let str = Fmt.str "Database error: %a." Caqti_error.pp err in
      let* () = Vif.Response.with_string req str in
      Vif.Response.respond `Internal_server_error