make config file and port optional

src/server.ml

@@ -32,7 +32,9 @@ struct
   let config =
     let filename = Fpath.(Project.config_dir / "config.scfg") in
     match Scfg.Parse.from_file filename with
-    | Error (`Msg msg) -> Fmt.failwith "%s" msg
+    | Error (`Msg _msg) ->
+      (* TODO: warn to say there is no config file! *)
+      []
     | Ok config -> config
 
   open Scfg.Query
@@ -40,7 +42,9 @@ struct
   let port =
     let directive = get_dir "port" config in
     match directive with
-    | None -> Fmt.failwith "configuration file is missing a port directive"
+    | None ->
+      (* TODO: warn to say we use a default port! *)
+      8080
     | Some directive -> (
       let param = get_param_int 0 directive in
       match param with