(*
- * 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_misc;;
open Hbugs_types;;
+open Printf;;
exception Client_already_in of client_id;;
exception Client_not_found of client_id;;
exception Tutor_already_in of tutor_id;;
exception Tutor_not_found of tutor_id;;
+class type registry =
+ object
+ method dump: string
+ method purge: unit
+ end
+
+let expire_time = 1800. (* 30 minutes *)
+
class clients =
object (self)
inherit ThreadSafe.threadSafe
+(*
+ (* <DEBUGGING> *)
+ method private doCritical: 'a. 'a lazy_t -> 'a = fun act -> Lazy.force act
+ method private doWriter: 'a. 'a lazy_t -> 'a = fun act -> Lazy.force act
+ method private doReader: 'a. 'a lazy_t -> 'a = fun act -> Lazy.force act
+ (* </DEBUGGING> *)
+*)
+ val timetable: (client_id, float) Hashtbl.t = Hashtbl.create 17
val urls: (client_id, string) Hashtbl.t = Hashtbl.create 17
val subscriptions: (client_id, tutor_id list) Hashtbl.t = Hashtbl.create 17
+ (** INVARIANT: each client registered has an entry in 'urls' hash table
+ _and_ in 'subscriptions hash table even if it hasn't yet invoked
+ 'subscribe' method *)
+
method register id url = self#doWriter (lazy (
if Hashtbl.mem urls id then
raise (Client_already_in id)
else begin
Hashtbl.add urls id url;
- Hashtbl.add subscriptions id []
+ Hashtbl.add subscriptions id [];
+ Hashtbl.add timetable id (Unix.time ())
end
))
+ method private remove id =
+ Hashtbl.remove urls id;
+ Hashtbl.remove subscriptions id;
+ Hashtbl.remove timetable id
method unregister id = self#doWriter (lazy (
- if Hashtbl.mem urls id then begin
- Hashtbl.remove urls id;
- Hashtbl.remove subscriptions id
- end else
+ if Hashtbl.mem urls id then
+ self#remove id
+ else
raise (Client_not_found id)
))
method isAuthenticated id = self#doReader (lazy (
raise (Client_not_found id)
))
+ method dump = self#doReader (lazy (
+ "<clients>\n" ^
+ (Hashtbl.fold
+ (fun id url dump ->
+ (dump ^
+ (sprintf "<client id=\"%s\" url=\"%s\">\n" id url) ^
+ "<subscriptions>\n" ^
+ (String.concat "\n" (* id's subscriptions *)
+ (List.map
+ (fun tutor_id -> sprintf "<tutor id=\"%s\" />\n" tutor_id)
+ (Hashtbl.find subscriptions id))) ^
+ "</subscriptions>\n</client>\n"))
+ urls "") ^
+ "</clients>"
+ ))
+ method purge = self#doWriter (lazy (
+ let now = Unix.time () in
+ Hashtbl.iter
+ (fun id birthday ->
+ if now -. birthday > expire_time then
+ self#remove id)
+ timetable
+ ))
+
end
class tutors =
object (self)
inherit ThreadSafe.threadSafe
+(*
+ (* <DEBUGGING> *)
+ method private doCritical: 'a. 'a lazy_t -> 'a = fun act -> Lazy.force act
+ method private doWriter: 'a. 'a lazy_t -> 'a = fun act -> Lazy.force act
+ method private doReader: 'a. 'a lazy_t -> 'a = fun act -> Lazy.force act
+ (* </DEBUGGING> *)
+*)
+ val timetable: (tutor_id, float) Hashtbl.t = Hashtbl.create 17
val tbl: (tutor_id, string * hint_type * string) Hashtbl.t =
Hashtbl.create 17
method register id url hint_type dsc = self#doWriter (lazy (
if Hashtbl.mem tbl id then
raise (Tutor_already_in id)
- else
- Hashtbl.add tbl id (url, hint_type, dsc)
+ else begin
+ Hashtbl.add tbl id (url, hint_type, dsc);
+ Hashtbl.add timetable id (Unix.time ())
+ end
))
+ method private remove id =
+ Hashtbl.remove tbl id;
+ Hashtbl.remove timetable id
method unregister id = self#doWriter (lazy (
if Hashtbl.mem tbl id then
- Hashtbl.remove tbl id
+ self#remove id
else
raise (Tutor_not_found id)
))
(fun id (url, hint_type, dsc) idx -> (id, dsc) :: idx) tbl []
))
+ method dump = self#doReader (lazy (
+ "<tutors>\n" ^
+ (Hashtbl.fold
+ (fun id (url, hint_type, dsc) dump ->
+ dump ^
+ (sprintf
+"<tutor id=\"%s\" url=\"%s\">\n<hint_type>%s</hint_type>\n<description>%s</description>\n</tutor>"
+ id url hint_type dsc))
+ tbl "") ^
+ "</tutors>"
+ ))
+ method purge = self#doWriter (lazy (
+ let now = Unix.time () in
+ Hashtbl.iter
+ (fun id birthday ->
+ if now -. birthday > expire_time then
+ self#remove id)
+ timetable
+ ))
+
end
class musings =
object (self)
inherit ThreadSafe.threadSafe
+(*
+ (* <DEBUGGING> *)
+ method private doCritical: 'a. 'a lazy_t -> 'a = fun act -> Lazy.force act
+ method private doWriter: 'a. 'a lazy_t -> 'a = fun act -> Lazy.force act
+ method private doReader: 'a. 'a lazy_t -> 'a = fun act -> Lazy.force act
+ (* </DEBUGGING> *)
+*)
+ val timetable: (musing_id, float) Hashtbl.t = Hashtbl.create 17
val musings: (musing_id, client_id * tutor_id) Hashtbl.t = Hashtbl.create 17
- val clients: (client_id, musing_id) Hashtbl.t = Hashtbl.create 17
- val tutors: (tutor_id, musing_id) Hashtbl.t = Hashtbl.create 17
+ val clients: (client_id, musing_id list) Hashtbl.t = Hashtbl.create 17
+ val tutors: (tutor_id, musing_id list) Hashtbl.t = Hashtbl.create 17
+
+ (** INVARIANT: each registered musing <musing_id, client_id, tutor_id> has
+ an entry in 'musings' table, an entry in 'clients' (i.e. one of the
+ musings for client_id is musing_id) table, an entry in 'tutors' table
+ (i.e. one of the musings for tutor_id is musing_id) and an entry in
+ 'timetable' table *)
+
method register musing_id client_id tutor_id = self#doWriter (lazy (
if Hashtbl.mem musings musing_id then
raise (Musing_already_in musing_id)
else begin
Hashtbl.add musings musing_id (client_id, tutor_id);
- Hashtbl.add clients client_id musing_id;
- Hashtbl.add tutors tutor_id musing_id
+ (* now add this musing as the first one of musings list for client and
+ tutor *)
+ Hashtbl.replace clients client_id
+ (musing_id ::
+ (try Hashtbl.find clients client_id with Not_found -> []));
+ Hashtbl.replace tutors tutor_id
+ (musing_id ::
+ (try Hashtbl.find tutors tutor_id with Not_found -> []));
+ Hashtbl.add timetable musing_id (Unix.time ())
end
))
+ method private remove id =
+ (* ASSUMPTION: this method is invoked under a 'writer' lock *)
+ let (client_id, tutor_id) = self#getByMusingId' id in
+ Hashtbl.remove musings id;
+ (* now remove this musing from the list of musings for client and tutor
+ *)
+ Hashtbl.replace clients client_id
+ (List.filter ((<>) id)
+ (try Hashtbl.find clients client_id with Not_found -> []));
+ Hashtbl.replace tutors tutor_id
+ (List.filter ((<>) id)
+ (try Hashtbl.find tutors tutor_id with Not_found -> []));
+ Hashtbl.remove timetable id
method unregister id = self#doWriter (lazy (
- if Hashtbl.mem musings id then begin
- Hashtbl.remove musings id;
- hashtbl_remove_all clients id;
- hashtbl_remove_all tutors id
- end
+ if Hashtbl.mem musings id then
+ self#remove id
))
- method getByMusingId id = self#doReader (lazy (
+ method private getByMusingId' id =
+ (* ASSUMPTION: this method is invoked under a 'reader' lock *)
try
Hashtbl.find musings id
with Not_found -> raise (Musing_not_found id)
+ method getByMusingId id = self#doReader (lazy (
+ self#getByMusingId' id
))
method getByClientId id = self#doReader (lazy (
- Hashtbl.find_all clients id
+ try
+ Hashtbl.find clients id
+ with Not_found -> []
))
method getByTutorId id = self#doReader (lazy (
- Hashtbl.find_all tutors id
+ try
+ Hashtbl.find tutors id
+ with Not_found -> []
+ ))
+ method isActive id = self#doReader (lazy (
+ Hashtbl.mem musings id
+ ))
+
+ method dump = self#doReader (lazy (
+ "<musings>\n" ^
+ (Hashtbl.fold
+ (fun mid (cid, tid) dump ->
+ dump ^
+ (sprintf "<musing id=\"%s\" client=\"%s\" tutor=\"%s\" />\n"
+ mid cid tid))
+ musings "") ^
+ "</musings>"
+ ))
+ method purge = self#doWriter (lazy (
+ let now = Unix.time () in
+ Hashtbl.iter
+ (fun id birthday ->
+ if now -. birthday > expire_time then
+ self#remove id)
+ timetable
))
end
projects / helm.git / blobdiff