src/dune

@@ -1,4 +1,4 @@
 (library
  (name mte)
  (wrapped false)
- (libraries logs h2))
+ (libraries logs h2 lwt))

src/mte.ml

@@ -39,8 +39,8 @@ let request_handler request =
   | [ "" ] ->
       let content = home_page_text in
       let headers = default_headers ~content `Text_plain in
-      { status= `OK; headers; content }
+      Lwt.return { status= `OK; headers; content }
   | _ ->
       let content = "Not found." in
       let headers = default_headers ~content `Text_plain in
-      { status= `Not_found; headers; content }
+      Lwt.return { status= `Not_found; headers; content }

unikernel/server.ml

@@ -16,26 +16,43 @@ let http_1_1_request_handler reqd =
   let request = H1.Reqd.request reqd in
   Log.debug (fun m ->
       m "(HTTP/1.1) request-handler: %S" request.H1.Request.target);
-  let Mte.{ status; headers; content } =
-    Mte.request_handler (request_from_h1 ~scheme:"http" request)
-  in
-  let status =
-    match status with
-    | #H1.Status.t as status -> status
-    | _ -> Fmt.failwith "H2 status response on a H1 request"
-  in
-  let headers = H1.Headers.of_list (Headers.to_list headers) in
-  let response = H1.Response.create ~headers status in
-  H1.Reqd.respond_with_string reqd response content
+  Lwt.async @@ fun () ->
+  Lwt.catch
+    (fun () ->
+      let open Syntax in
+      let+ Mte.{ status; headers; content } =
+        Mte.request_handler (request_from_h1 ~scheme:"http" request)
+      in
+      let status =
+        match status with
+        | #H1.Status.t as status -> status
+        | _ -> Fmt.failwith "H2 status response on a H1 request"
+      in
+      let headers = H1.Headers.of_list (Headers.to_list headers) in
+      let response = H1.Response.create ~headers status in
+      H1.Reqd.respond_with_string reqd response content;
+      ())
+    (fun exn ->
+      (* note: not sure what this does exactly, this is what is done in Dream *)
+      H1.Reqd.report_exn reqd exn;
+      Lwt.return_unit)
 
 let http_2_0_request_handler reqd =
   let request = H2.Reqd.request reqd in
   Log.debug (fun m -> m "(H2) request-handler: %S" request.H2.Request.target);
-  let Mte.{ status; headers; content } =
-    Mte.request_handler (request_from_h2 request)
-  in
-  let response = H2.Response.create ~headers status in
-  H2.Reqd.respond_with_string reqd response content
+  Lwt.async @@ fun () ->
+  Lwt.catch
+    (fun () ->
+      let open Syntax in
+      let+ Mte.{ status; headers; content } =
+        Mte.request_handler (request_from_h2 request)
+      in
+      let response = H2.Response.create ~headers status in
+      H2.Reqd.respond_with_string reqd response content;
+      ())
+    (fun exn ->
+      H2.Reqd.report_exn reqd exn;
+      Lwt.return_unit)
 
 let alpn_request_handler : type reqd headers request response ro wo.
     reqd -> (reqd, headers, request, response, ro, wo) Alpn.protocol -> unit =