try to download selenium

.gitignore

@@ -1 +1,3 @@
 _build/
+
+/selenium-*.jar

bin/main.ml

@@ -1 +1,29 @@
-let () = print_endline "Hello, World!"
+open Lwt.Syntax
+open Cohttp_lwt
+open Cohttp_lwt_unix
+
+let fmt = Printf.sprintf
+
+let download uri dest =
+  let* response, body = Client.get uri in
+  let status = Response.status response in
+  if Cohttp.Code.code_of_status status = 302
+  then (
+    print_endline (fmt "\nDownloading %s ..." (Uri.to_string uri));
+    let stream = Body.to_stream body in
+    Lwt_io.with_file ~mode:Lwt_io.output dest (fun chan ->
+        Lwt_stream.iter_s (Lwt_io.write chan) stream))
+  else
+    Lwt.fail_with
+      ("Failed to download file. HTTP status: " ^ Cohttp.Code.string_of_status status)
+;;
+
+let download_selenium version =
+  let url =
+    format_of_string
+      "https://github.com/SeleniumHQ/selenium/releases/download/selenium-%s/selenium-server-%s.jar"
+  in
+  download (Uri.of_string (fmt url version version)) (fmt "./selenium-%s.jar" version)
+;;
+
+let () = Lwt_main.run (download_selenium "4.9.0")