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|
open Core
open Async
open Websocket_async
let () = Logs.set_reporter (Logs_async_reporter.reporter ())
let client protocol extensions uri =
let host = Option.value_exn ~message:"no host in uri" Uri.(host uri) in
let port =
match (Uri.port uri, Uri_services.tcp_port_of_uri uri) with
| Some p, _ -> p
| None, Some p -> p
| _ -> invalid_arg "port cannot be inferred from URL"
in
let scheme = Option.value_exn ~message:"no scheme in uri" Uri.(scheme uri) in
let tcp_fun (r, w) =
let module C = Cohttp in
let extra_headers = C.Header.init () in
let extra_headers =
Option.value_map protocol ~default:extra_headers ~f:(fun proto ->
C.Header.add extra_headers "Sec-Websocket-Protocol" proto)
in
let extra_headers =
Option.value_map extensions ~default:extra_headers ~f:(fun exts ->
C.Header.add extra_headers "Sec-Websocket-Extensions" exts)
in
let r, w =
client_ez ~extra_headers ~heartbeat:Time_ns.Span.(of_int_sec 5) uri r w
in
Deferred.all_unit
[
Pipe.transfer
Reader.(pipe @@ Lazy.force stdin)
w
~f:(fun s -> String.chop_suffix_exn s ~suffix:"\n");
Pipe.transfer r
Writer.(pipe @@ Lazy.force stderr)
~f:(fun s -> s ^ "\n");
]
in
Unix.Addr_info.get ~service:(string_of_int port) ~host [] >>= function
| [] -> failwithf "DNS resolution failed for %s" host ()
| { ai_addr; _ } :: _ ->
let addr =
match (scheme, ai_addr) with
| _, ADDR_UNIX path -> `Unix_domain_socket path
| "https", ADDR_INET (h, p) | "wss", ADDR_INET (h, p) ->
let h = Ipaddr_unix.of_inet_addr h in
`OpenSSL (h, p, Conduit_async.V2.Ssl.Config.create ())
| _, ADDR_INET (h, p) ->
let h = Ipaddr_unix.of_inet_addr h in
`TCP (h, p)
in
Conduit_async.V2.connect addr >>= tcp_fun
let src = Logs.Src.create "websocket.wscat"
let handle_client addr reader writer =
let addr_str = Socket.Address.(to_string addr) in
Logs_async.info ~src (fun m -> m "Client connection from %s" addr_str)
>>= fun () ->
let app_to_ws, sender_write = Pipe.create () in
let receiver_read, ws_to_app = Pipe.create () in
let check_request req =
Logs_async.info ~src (fun m ->
m "Incoming connnection request: %a" Cohttp.Request.pp_hum req)
>>= fun () ->
Deferred.return (String.equal Cohttp.Request.(uri req |> Uri.path) "/ws")
in
let rec loop () =
Pipe.read receiver_read >>= function
| `Eof ->
Logs_async.info ~src (fun m -> m "Client %s disconnected" addr_str)
| `Ok ({ Frame.opcode; content; _ } as frame) ->
let open Frame in
Logs_async.debug ~src (fun m -> m "<- %a" Frame.pp frame) >>= fun () ->
let frame', closed =
match opcode with
| Opcode.Ping -> (Some (create ~opcode:Opcode.Pong ~content ()), false)
| Opcode.Close ->
(* Immediately echo and pass this last message to the user *)
if String.length content >= 2 then
( Some
(create ~opcode:Opcode.Close
~content:(String.sub content ~pos:0 ~len:2)
()),
true )
else (Some (close 100), true)
| Opcode.Pong -> (None, false)
| Opcode.Text | Opcode.Binary -> (Some frame, false)
| _ -> (Some (close 1002), false)
in
(match frame' with
| None -> Deferred.unit
| Some frame' ->
Logs_async.debug ~src (fun m -> m "-> %a" pp frame') >>= fun () ->
Pipe.write sender_write frame')
>>= fun () -> if closed then Deferred.unit else loop ()
in
Deferred.any
[
(server ~check_request ~app_to_ws ~ws_to_app ~reader ~writer ()
>>= function
| Error err when Poly.equal (Error.to_exn err) Exit -> Deferred.unit
| Error err -> Error.raise err
| Ok () -> Deferred.unit);
loop ();
]
let command =
let spec =
let open Command.Spec in
empty
+> flag "-protocol" (optional string) ~doc:"str websocket protocol header"
+> flag "-extensions" (optional string)
~doc:"str websocket extensions header"
+> flag "-loglevel" (optional int) ~doc:"1-3 loglevel"
+> flag "-s" no_arg ~doc:" Run as server (default: no)"
+> anon ("url" %: string)
in
let set_loglevel = function
| 2 -> Logs.set_level (Some Info)
| 3 -> Logs.set_level (Some Debug)
| _ -> ()
in
let run protocol extension loglevel is_server url () =
Option.iter loglevel ~f:set_loglevel;
let url = Uri.of_string url in
match is_server with
| false -> client protocol extension url
| true ->
let port =
Option.value_exn ~message:"no port inferred from scheme"
Uri_services.(tcp_port_of_uri url)
in
Tcp.(
Server.create ~on_handler_error:`Ignore
Where_to_listen.(of_port port)
handle_client)
>>= Tcp.Server.close_finished
in
Command.async_spec ~summary:"telnet-like interface to Websockets" spec run
let () = Command_unix.run command
|
