hop-2012/ui_relay.ml

99 lines
3.4 KiB
OCaml

(* Copyright 2012 Tony Garnock-Jones <tonygarnockjones@gmail.com>. *)
(* This file is part of Hop. *)
(* Hop is free software: you can redistribute it and/or modify it *)
(* under the terms of the GNU General Public License as published by the *)
(* Free Software Foundation, either version 3 of the License, or (at your *)
(* option) any later version. *)
(* Hop is distributed in the hope that it will be useful, but *)
(* WITHOUT ANY WARRANTY; without even the implied warranty of *)
(* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU *)
(* General Public License for more details. *)
(* You should have received a copy of the GNU General Public License *)
(* along with Hop. If not, see <http://www.gnu.org/licenses/>. *)
open Lwt
open Hof
let rec api_tap_source id r =
let mbox = Lwt_mvar.create
(Some (Message.subscribe (Sexp.Str (Node.local_container_name()),
Sexp.Str "", Sexp.Str "",
Sexp.Str "", Sexp.Str ""))) in
let handle_message n sexp = Lwt_mvar.put mbox (Some sexp) in
let n = Node.make "http_tap" handle_message in
let shutdown () =
lwt () = Node.unbind_all n in
Lwt_mvar.put mbox None
in
let generator yield =
let body_counter = ref 0 in
let yield_and_count s =
body_counter := String.length s + !body_counter;
yield s
in
lwt () = yield_and_count (id.Node.label ^ ";" ^ String.make 2048 'h' ^ ";") in
let rec drain_mbox () =
match_lwt Lwt_mvar.take mbox with
| None -> return ()
| Some sexp ->
lwt json = Sexpjson.json_of_sexp sexp in
let payload = Json.to_string json in
lwt () = yield_and_count (Printf.sprintf "%d;%s;" (String.length payload) payload) in
lwt () =
if !body_counter >= 131072
then shutdown ()
else return ()
in
drain_mbox ()
in drain_mbox ()
in
match_lwt Node.bind (id, n) with
| false -> Httpd.http_error_html 500 "Internal ID collision" []
| true ->
Httpd.resp_generic 200 "Streaming"
[Httpd.text_content_type_header;
"Access-Control-Allow-Origin", "*"]
(Httpd.Variable (Streamutil.stream_generator generator))
|> Httpd.add_disable_cache_headers
|> Httpd.add_date_header
|> Httpd.add_completion_callback shutdown
let api_tap_sink irrelevant_id r =
lwt content = Httpd.string_of_content r.Httpd.req_body.Httpd.content in
lwt params = Httpd.parse_urlencoded content in
match Httpd.find_param "metadata.type" params with
| Some (Some "send") ->
(match Httpd.find_param "data" params with
| Some (Some data_str) ->
lwt data =
(try return (Sexpjson.sexp_of_json (Json.of_string data_str))
with _ -> Httpd.http_error_html 406 "Bad data parameter" []) in
(match Message.message_of_sexp data with
| Message.Post (Sexp.Str name, body, token) ->
lwt () = Node.send_ignore' name body in
Httpd.resp_generic 202 "Accepted" [] (Httpd.empty_content)
| _ ->
Httpd.http_error_html 406 "Message not understood" [])
| _ -> Httpd.http_error_html 406 "Bad data parameter" [])
| Some (Some "close") ->
Httpd.resp_generic_ok [] Httpd.empty_content
| _ ->
Httpd.http_error_html 406 "Unsupported metadata.type" []
let api_tap _ id r =
match r.Httpd.verb with
| "GET" -> api_tap_source id r
| "POST" -> api_tap_sink id r
| _ -> Httpd.http_error_html 400 "Unsupported tap method" []
let init () =
Ui_main.register_dispatcher ("/_/tap", api_tap)