unikernel/duniverse/ocaml-tls/lwt/examples/echo_client_alpn.ml

@@ -0,0 +1,22 @@
+
+open Ex_common
+open Lwt
+
+let echo_client host port =
+  let open Lwt_io in
+  let port = int_of_string port in
+  let authenticator = null_auth in
+  Tls_lwt.Unix.connect
+    (get_ok Tls.Config.(client ~authenticator ~alpn_protocols:["http/1.1"; "h2"] ()))
+    (host, port) >>= fun t ->
+  match Tls_lwt.Unix.epoch t with
+  | Error () -> printl "Error"
+  | Ok epoch -> (
+    match epoch.Tls.Core.alpn_protocol with
+      | None -> printl "No protocol selected"
+      | Some protocol -> printl ("Selected protocol: " ^ protocol)
+  )
+    >>= fun () -> Tls_lwt.Unix.close t
+
+let () =
+  Lwt_main.run (echo_client "127.0.0.1" "4433")