a-error.txt

For `(Router.callback router ())` in Index.re:

      Error: The types don't match.
      This is: Cohttp_lwt_unix.Request.t -> 'a -> 'b
      Wanted:  Cohttp_lwt_unix.Server.conn ->
               Cohttp.Request.t ->
               Cohttp_lwt_body.t -> (Cohttp.Response.t * Cohttp_lwt_body.t) Lwt.t

Index.re

open Lwt;

open Cohttp;

open Cohttp_lwt_unix;

let module Util = Yojson.Basic.Util;

let router =
  Router.add_route
    (Router.create ())
    "/"
    (
      fun req body =>
        Cohttp_lwt_body.to_string body >>= (
          fun body => {
            let json = Yojson.Basic.from_string body;
            let synced_from = json |> Util.member "synced_from" |> Util.to_string;
            let response = Yojson.Basic.to_string (
              `Assoc [
                ("id", `String (Uuidm.to_string (Uuidm.v `V4))),
                ("devices", `String synced_from)
              ]
            );
            Server.respond_string status::`OK body::response ()
          }
        )
    );

let server =
  Server.create mode::(`TCP (`Port 8000)) (Server.make callback::(Router.callback router ()) ());

ignore (Lwt_main.run server);

Router.re

open Lwt;

open Cohttp;

open Cohttp_lwt_unix;

let create () => [];

let add_route router url handler => [(url, handler), ...router];

let callback router => {
  let routes = List.rev router;
  fun _conn req body => {
    let uri = req |> Request.uri |> Uri.to_string;
    let (url, handler) = List.find (fun (url, handler) => url == uri) routes;
    handler req body
  }
};