add custom middleware - count requests

bin/nikodream.ml

@@ -1,11 +1,23 @@
+let count = ref 0
+
+(* middleware *)
+let count_requests inner_handler request =
+  count := !count + 1;
+  inner_handler request
+
 let () =
   Dream.run
   @@ Dream.logger
+  @@ count_requests
   @@ Dream.router [
     Dream.get "/"
       (fun _ ->
         Dream.html "Hello, world!");
 
+    Dream.get "/count"
+      (fun _ ->
+        Dream.html (Printf.sprintf "Saw %i requests" !count));
+
     Dream.get "/echo/:word"
       (fun request ->
         Dream.html (Dream.param request "word"));