(*
- * Copyright (C) 2003, HELM Team.
+ * Copyright (C) 2003:
+ * Stefano Zacchiroli <zack@cs.unibo.it>
+ * for the HELM Team http://helm.cs.unibo.it/
*
* This file is part of HELM, an Hypertextual, Electronic
* Library of Mathematics, developed at the Computer Science
* MA 02111-1307, USA.
*
* For details, see the HELM World-Wide-Web page,
- * http://cs.unibo.it/helm/.
+ * http://helm.cs.unibo.it/
*)
open Hbugs_types;;
let debug = true ;;
let debug_print s = if debug then prerr_endline s ;;
+Http_common.debug := false;;
let daemon_name = "H-Bugs Broker" ;;
let default_port = 49081 ;;
prerr_endline "Warning: invalid port, reverting to default";
default_port
;;
+let usage_string = "HBugs Broker: usage string not yet written :-(";;
exception Unexpected_msg of message;;
-let xml_contype = ("Content-Type", "text/xml") ;;
let return_xml_msg body outchan =
- Http_daemon.respond ~headers:[xml_contype] ~body outchan
-;;
-let return_hbugs_msg msg = return_xml_msg (Hbugs_messages.string_of_msg msg);;
-let return_hbugs_exc name value = return_hbugs_msg (Exception (name, value));;
-let send_hbugs_req ~url msg =
- Hbugs_messages.msg_of_string
- (Hbugs_misc.http_post ~body:(Hbugs_messages.string_of_msg msg) url)
+ Http_daemon.respond ~headers:["Content-Type", "text/xml"] ~body outchan
;;
let parse_musing_id = function
- | Musing_started (_, musing_id) -> musing_id
+ | Musing_started (_, musing_id) ->
+ prerr_endline ("#### Started musing ID: " ^ musing_id);
+ musing_id
| Musing_aborted (_, musing_id) -> musing_id
- | _ -> assert false
+ | msg ->
+ prerr_endline (sprintf "Assertion failed, received msg: %s"
+ (Hbugs_messages.string_of_msg msg));
+ assert false
;;
let do_critical =
let mutex = Mutex.create () in
fun action ->
try
- Mutex.lock mutex; let res = Lazy.force action in Mutex.unlock mutex; res
+(* debug_print "Acquiring lock ..."; *)
+ Mutex.lock mutex;
+(* debug_print "Lock Acquired!"; *)
+ let res = Lazy.force action in
+(* debug_print "Releaseing lock ..."; *)
+ Mutex.unlock mutex;
+(* debug_print "Lock released!"; *)
+ res
with e -> Mutex.unlock mutex; raise e
;;
+ (* registries *)
let clients = new Hbugs_broker_registry.clients in
let tutors = new Hbugs_broker_registry.tutors in
let musings = new Hbugs_broker_registry.musings in
+let registries =
+ [ (clients :> Hbugs_broker_registry.registry);
+ (tutors :> Hbugs_broker_registry.registry);
+ (musings :> Hbugs_broker_registry.registry) ]
+in
+
let my_own_id = Hbugs_id_generator.new_broker_id () in
-let handle_msg outchan = function
+ (* debugging: dump broker internal status, used by '/dump' method *)
+let dump_registries () =
+ assert debug;
+ String.concat "\n" (List.map (fun o -> o#dump) registries)
+in
+let handle_msg outchan msg =
(* messages from clients *)
+ (match msg with
+
+ | Help ->
+ Hbugs_messages.respond_msg (Usage usage_string) outchan
| Register_client (client_id, client_url) -> do_critical (lazy (
- debug_print "Register_client";
try
clients#register client_id client_url;
- return_hbugs_msg (Client_registered my_own_id) outchan
+ Hbugs_messages.respond_msg (Client_registered my_own_id) outchan
with Hbugs_broker_registry.Client_already_in id ->
- return_hbugs_exc "already_registered" id outchan
+ Hbugs_messages.respond_exc "already_registered" id outchan
))
| Unregister_client client_id -> do_critical (lazy (
- debug_print "Unregister_client";
if clients#isAuthenticated client_id then begin
clients#unregister client_id;
- return_hbugs_msg (Client_unregistered my_own_id) outchan
+ Hbugs_messages.respond_msg (Client_unregistered my_own_id) outchan
end else
- return_hbugs_exc "forbidden" client_id outchan
+ Hbugs_messages.respond_exc "forbidden" client_id outchan
))
| List_tutors client_id -> do_critical (lazy (
- debug_print "List_tutors";
if clients#isAuthenticated client_id then begin
- return_hbugs_msg (Tutor_list (my_own_id, tutors#index)) outchan
+ Hbugs_messages.respond_msg
+ (Tutor_list (my_own_id, tutors#index))
+ outchan
end else
- return_hbugs_exc "forbidden" client_id outchan
+ Hbugs_messages.respond_exc "forbidden" client_id outchan
))
| Subscribe (client_id, tutor_ids) -> do_critical (lazy (
- debug_print "Subscribe";
if clients#isAuthenticated client_id then begin
- if List.for_all tutors#exists tutor_ids then begin
- clients#subscribe client_id tutor_ids;
- return_hbugs_msg (Subscribed (my_own_id, tutor_ids)) outchan
- end else (* required subscription to an unexistent tutor *)
- let tutor_id =
- List.find (fun id -> not (tutors#exists id)) tutor_ids
- in
- return_hbugs_exc "tutor_not_found" tutor_id outchan
+ if List.length tutor_ids <> 0 then begin (* at least one tutor id *)
+ if List.for_all tutors#exists tutor_ids then begin
+ clients#subscribe client_id tutor_ids;
+ Hbugs_messages.respond_msg
+ (Subscribed (my_own_id, tutor_ids)) outchan
+ end else (* required subscription to at least one unexistent tutor *)
+ let missing_tutors =
+ List.filter (fun id -> not (tutors#exists id)) tutor_ids
+ in
+ Hbugs_messages.respond_exc
+ "tutor_not_found" (String.concat " " missing_tutors) outchan
+ end else (* no tutor id specified *)
+ Hbugs_messages.respond_exc "no_tutor_specified" "" outchan
end else
- return_hbugs_exc "forbidden" client_id outchan
+ Hbugs_messages.respond_exc "forbidden" client_id outchan
))
| State_change (client_id, new_state) -> do_critical (lazy (
- debug_print "State_change";
if clients#isAuthenticated client_id then begin
let active_musings = musings#getByClientId client_id in
+ prerr_endline (sprintf "ACTIVE MUSINGS: %s" (String.concat ", " active_musings));
+ if List.length active_musings = 0 then
+ prerr_endline ("No active musings for client " ^ client_id);
+ prerr_endline "CSC: State change!!!" ;
let stop_answers =
List.map (* collect Abort_musing message's responses *)
(fun id -> (* musing id *)
let tutor = snd (musings#getByMusingId id) in
- send_hbugs_req
+ Hbugs_messages.submit_req
~url:(tutors#getUrl tutor) (Abort_musing (my_own_id, id)))
active_musings
in
+ let stopped_musing_ids = List.map parse_musing_id stop_answers in
List.iter musings#unregister active_musings;
- let started_musing_ids =
- List.map (* register new musings and collect their ids *)
- (fun tutor_id ->
- let res =
- send_hbugs_req
- ~url:(tutors#getUrl tutor_id)
- (Start_musing (my_own_id, new_state))
- in
- let musing_id = parse_musing_id res in
- musings#register musing_id client_id tutor_id;
- musing_id)
- (clients#getSubscription client_id)
- in
- let stopped_musing_ids = List.map parse_musing_id stop_answers in
- return_hbugs_msg
- (State_accepted (my_own_id, stopped_musing_ids, started_musing_ids))
- outchan
+ (match new_state with
+ | Some new_state -> (* need to start new musings *)
+ let subscriptions = clients#getSubscription client_id in
+ if List.length subscriptions = 0 then
+ prerr_endline ("No subscriptions for client " ^ client_id);
+ let started_musing_ids =
+ List.map (* register new musings and collect their ids *)
+ (fun tutor_id ->
+ let res =
+ Hbugs_messages.submit_req
+ ~url:(tutors#getUrl tutor_id)
+ (Start_musing (my_own_id, new_state))
+ in
+ let musing_id = parse_musing_id res in
+ musings#register musing_id client_id tutor_id;
+ musing_id)
+ subscriptions
+ in
+ Hbugs_messages.respond_msg
+ (State_accepted (my_own_id, stopped_musing_ids, started_musing_ids))
+ outchan
+ | None -> (* no need to start new musings *)
+ Hbugs_messages.respond_msg
+ (State_accepted (my_own_id, stopped_musing_ids, []))
+ outchan)
end else
- return_hbugs_exc "forbidden" client_id outchan
+ Hbugs_messages.respond_exc "forbidden" client_id outchan
))
(* messages from tutors *)
+
| Register_tutor (tutor_id, tutor_url, hint_type, dsc) -> do_critical (lazy (
- debug_print "Register_tutor";
try
tutors#register tutor_id tutor_url hint_type dsc;
- return_hbugs_msg (Tutor_registered my_own_id) outchan
+ Hbugs_messages.respond_msg (Tutor_registered my_own_id) outchan
with Hbugs_broker_registry.Tutor_already_in id ->
- return_hbugs_exc "already_registered" id outchan
+ Hbugs_messages.respond_exc "already_registered" id outchan
))
| Unregister_tutor tutor_id -> do_critical (lazy (
- debug_print "Unregister_tutor";
if tutors#isAuthenticated tutor_id then begin
tutors#unregister tutor_id;
- return_hbugs_msg (Tutor_unregistered my_own_id) outchan
+ Hbugs_messages.respond_msg (Tutor_unregistered my_own_id) outchan
end else
- return_hbugs_exc "forbidden" tutor_id outchan
+ Hbugs_messages.respond_exc "forbidden" tutor_id outchan
))
+
| Musing_completed (tutor_id, musing_id, result) -> do_critical (lazy (
- debug_print "Musing_completed";
- if tutors#isAuthenticated tutor_id then begin
+ if not (tutors#isAuthenticated tutor_id) then begin (* unauthorized *)
+ Hbugs_messages.respond_exc "forbidden" tutor_id outchan;
+ end else if not (musings#isActive musing_id) then begin (* too late *)
+ Hbugs_messages.respond_msg (Too_late (my_own_id, musing_id)) outchan;
+ end else begin (* all is ok: autorhized and on time *)
(match result with
| Sorry -> ()
- | Eureka extras ->
+ | Eureka hint ->
+ let client_url =
+ clients#getUrl (fst (musings#getByMusingId musing_id))
+ in
let res =
- let hint = (* TODO decidere la hint *) "hint!!!!" in
- let url =
- clients#getUrl (fst (musings#getByMusingId musing_id))
- in
- send_hbugs_req ~url (Hint (my_own_id, hint))
+ Hbugs_messages.submit_req ~url:client_url (Hint (my_own_id, hint))
in
- ignore res (* TODO mi interessa la risposta? *)
- );
- return_hbugs_msg (Thanks (my_own_id, musing_id)) outchan;
+ (match res with
+ | Wow _ -> () (* ok: client is happy with our hint *)
+ | unexpected_msg ->
+ prerr_endline
+ (sprintf
+ "Warning: unexpected msg from client: %s\nExpected was: Wow"
+ (Hbugs_messages.string_of_msg msg))));
+ Hbugs_messages.respond_msg (Thanks (my_own_id, musing_id)) outchan;
musings#unregister musing_id
- end else
- return_hbugs_exc "forbidden" tutor_id outchan
+ end
))
| msg -> (* unexpected message *)
debug_print "Unknown message!";
- return_hbugs_msg
- (Exception ("Unexpected_msg", Hbugs_messages.string_of_msg msg))
- outchan
+ Hbugs_messages.respond_exc
+ "unexpected_msg" (Hbugs_messages.string_of_msg msg) outchan)
+in
+(* (* DEBUGGING wrapper around 'handle_msg' *)
+let handle_msg outchan =
+ if debug then
+ (fun msg -> (* filter handle_msg through a function which dumps input
+ messages *)
+ debug_print (Hbugs_messages.string_of_msg msg);
+ handle_msg outchan msg)
+ else
+ handle_msg outchan
in
+*)
(* thread action *)
let callback (req: Http_types.request) outchan =
(match req#path with
(* TODO write help message *)
| "/help" -> return_xml_msg "<help> not yet written </help>" outchan
- | "/act" -> handle_msg outchan (Hbugs_messages.msg_of_string req#body)
+ | "/act" ->
+ let msg = Hbugs_messages.msg_of_string req#body in
+ handle_msg outchan msg
+ | "/dump" ->
+ if debug then
+ Http_daemon.respond ~body:(dump_registries ()) outchan
+ else
+ Http_daemon.respond_error ~code:400 outchan
| _ -> Http_daemon.respond_error ~code:400 outchan);
debug_print "Done!\n"
with
| Http_types.Param_not_found attr_name ->
- return_hbugs_exc "missing_parameter" attr_name outchan
+ Hbugs_messages.respond_exc "missing_parameter" attr_name outchan
| exc ->
- return_hbugs_exc "uncaught_exception" (Printexc.to_string exc) outchan
+ Hbugs_messages.respond_exc
+ "uncaught_exception" (Printexc.to_string exc) outchan
+in
+
+ (* thread who cleans up ancient client/tutor/musing registrations *)
+let ragman () =
+ let delay = 3600.0 in (* 1 hour delay *)
+ while true do
+ Thread.delay delay;
+ List.iter (fun o -> o#purge) registries
+ done
in
-(* TODO aggiungere lo spazzino che elimina i client/tutor/computation che non si
-fanno sentire da troppo tempo ... *)
- (* start daemon *)
+ (* start daemon *)
printf "Listening on port %d ...\n" port;
flush stdout;
+ignore (Thread.create ragman ());
Http_daemon.start' ~port ~mode:`Thread callback
projects / helm.git / blobdiff