Merge remote-tracking branch 'processone/pr/2763'

* processone/pr/2763:
  disallow room creation if archive not empty and clear_archive_on_room_destroy is false
  check if mod_mam is loaded before calling mod_mam:is_empty_for_room
  added cmds to list and destroy empty rooms by ejabberdctl
  allow check if archive is empty for or user or room
  option to prevent archive removal on room destroy

5 files changed, 137 insertions, 29 deletions

diff --git a/src/mod_mam.erl b/src/mod_mam.erl
index 294d4f401..7dc80e462 100644
--- a/src/mod_mam.erl
+++ b/src/mod_mam.erl
@@ -40,7 +40,8 @@
 	 muc_process_iq/2, muc_filter_message/3, message_is_archived/3,
 	 delete_old_messages/2, get_commands_spec/0, msg_to_el/4,
 	 get_room_config/4, set_room_option/3, offline_message/1, export/1,
-	 mod_options/1, remove_mam_for_user_with_peer/3, remove_mam_for_user/2]).
+	 mod_options/1, remove_mam_for_user_with_peer/3, remove_mam_for_user/2,
+	 is_empty_for_user/2, is_empty_for_room/3, check_create_room/4]).
 
 -include("xmpp.hrl").
 -include("logger.hrl").
@@ -72,6 +73,8 @@
 -callback use_cache(binary()) -> boolean().
 -callback cache_nodes(binary()) -> [node()].
 -callback remove_from_archive(binary(), binary(), jid() | none) -> ok | {error, any()}.
+-callback is_empty_for_user(binary(), binary()) -> boolean().
+-callback is_empty_for_room(binary(), binary(), binary()) -> boolean().
 
 -optional_callbacks([use_cache/1, cache_nodes/1]).
 
@@ -113,8 +116,6 @@ start(Host, Opts) ->
 			       disco_sm_features, 50),
 	    ejabberd_hooks:add(remove_user, Host, ?MODULE,
 			       remove_user, 50),
-	    ejabberd_hooks:add(remove_room, Host, ?MODULE,
-			       remove_room, 50),
 	    ejabberd_hooks:add(get_room_config, Host, ?MODULE,
 			       get_room_config, 50),
 	    ejabberd_hooks:add(set_room_option, Host, ?MODULE,
@@ -126,11 +127,22 @@ start(Host, Opts) ->
 		false ->
 		    ok
 	    end,
+	    case gen_mod:get_opt(clear_archive_on_room_destroy, Opts) of
+		true ->
+		    ejabberd_hooks:add(remove_room, Host, ?MODULE,
+				       remove_room, 50);
+		false ->
+		    ejabberd_hooks:add(check_create_room, Host, ?MODULE,
+				       check_create_room, 50)
+	    end,
 	    ejabberd_commands:register_commands(get_commands_spec());
 	Err ->
 	    Err
     end.
 
+
+
+
 use_cache(Mod, Host) ->
     case erlang:function_exported(Mod, use_cache, 2) of
 	true -> Mod:use_cache(Host);
@@ -180,8 +192,6 @@ stop(Host) ->
 			  disco_sm_features, 50),
     ejabberd_hooks:delete(remove_user, Host, ?MODULE,
 			  remove_user, 50),
-    ejabberd_hooks:delete(remove_room, Host, ?MODULE,
-			  remove_room, 50),
     ejabberd_hooks:delete(get_room_config, Host, ?MODULE,
 			  get_room_config, 50),
     ejabberd_hooks:delete(set_room_option, Host, ?MODULE,
@@ -193,6 +203,14 @@ stop(Host) ->
 	false ->
 	    ok
     end,
+    case gen_mod:get_module_opt(Host, ?MODULE, clear_archive_on_room_destroy) of
+	true ->
+	    ejabberd_hooks:delete(remove_room, Host, ?MODULE,
+				  remove_room, 50);
+	false ->
+	    ejabberd_hooks:delete(check_create_room, Host, ?MODULE,
+				  check_create_room, 50)
+    end,
     case gen_mod:is_loaded_elsewhere(Host, ?MODULE) of
         false ->
             ejabberd_commands:unregister_commands(get_commands_spec());
@@ -559,6 +577,24 @@ export(LServer) ->
     Mod = gen_mod:db_mod(LServer, ?MODULE),
     Mod:export(LServer).
 
+-spec is_empty_for_user(binary(), binary()) -> boolean().
+is_empty_for_user(User, Server) ->
+    LUser = jid:nodeprep(User),
+    LServer = jid:nameprep(Server),
+    Mod = gen_mod:db_mod(LServer, ?MODULE),
+    Mod:is_empty_for_user(LUser, LServer).
+
+-spec is_empty_for_room(binary(), binary(), binary()) -> boolean().
+is_empty_for_room(LServer, Name, Host) ->
+    LName = jid:nodeprep(Name),
+    LHost = jid:nameprep(Host),
+    Mod = gen_mod:db_mod(LServer, ?MODULE),
+    Mod:is_empty_for_room(LServer, LName, LHost).
+
+-spec check_create_room(boolean(), binary(), binary(), binary()) -> boolean().
+check_create_room(Acc, ServerHost, RoomID, Host) ->
+    Acc and is_empty_for_room(ServerHost, RoomID, Host).
+
 %%%===================================================================
 %%% Internal functions
 %%%===================================================================
@@ -1211,6 +1247,8 @@ mod_opt_type(default) ->
 	(roster) -> roster
     end;
 mod_opt_type(request_activates_archiving) ->
+    fun (B) when is_boolean(B) -> B end;
+mod_opt_type(clear_archive_on_room_destroy) ->
     fun (B) when is_boolean(B) -> B end.
 
 mod_options(Host) ->
@@ -1218,6 +1256,7 @@ mod_options(Host) ->
      {default, never},
      {request_activates_archiving, false},
      {compress_xml, false},
+     {clear_archive_on_room_destroy, true},
      {db_type, ejabberd_config:default_db(Host, ?MODULE)},
      {use_cache, ejabberd_config:use_cache(Host)},
      {cache_size, ejabberd_config:cache_size(Host)},
diff --git a/src/mod_mam_mnesia.erl b/src/mod_mam_mnesia.erl
index 08d551585..f94dd2e49 100644
--- a/src/mod_mam_mnesia.erl
+++ b/src/mod_mam_mnesia.erl
@@ -28,7 +28,8 @@
 
 %% API
 -export([init/2, remove_user/2, remove_room/3, delete_old_messages/3,
-	 extended_fields/0, store/8, write_prefs/4, get_prefs/2, select/6, remove_from_archive/3]).
+	 extended_fields/0, store/8, write_prefs/4, get_prefs/2, select/6, remove_from_archive/3,
+	 is_empty_for_user/2, is_empty_for_room/3]).
 
 -include_lib("stdlib/include/ms_transform.hrl").
 -include("xmpp.hrl").
@@ -198,6 +199,13 @@ select(_LServer, JidRequestor,
     erlang:garbage_collect(),
     Result.
 
+is_empty_for_user(LUser, LServer) ->
+	not lists:member({LUser, LServer},
+		mnesia:dirty_all_keys(archive_msg)).
+
+is_empty_for_room(_LServer, LName, LHost) ->
+    is_empty_for_user(LName, LHost).
+
 %%%===================================================================
 %%% Internal functions
 %%%===================================================================
diff --git a/src/mod_mam_sql.erl b/src/mod_mam_sql.erl
index bcfa06708..6242de3c6 100644
--- a/src/mod_mam_sql.erl
+++ b/src/mod_mam_sql.erl
@@ -30,7 +30,8 @@
 
 %% API
 -export([init/2, remove_user/2, remove_room/3, delete_old_messages/3,
-	 extended_fields/0, store/8, write_prefs/4, get_prefs/2, select/6, export/1, remove_from_archive/3]).
+	 extended_fields/0, store/8, write_prefs/4, get_prefs/2, select/6, export/1, remove_from_archive/3,
+	 is_empty_for_user/2, is_empty_for_room/3]).
 
 -include_lib("stdlib/include/ms_transform.hrl").
 -include("xmpp.hrl").
@@ -264,6 +265,23 @@ export(_Server) ->
               []
       end}].
 
+is_empty_for_user(LUser, LServer) ->
+    case ejabberd_sql:sql_query(
+	   LServer,
+	   ?SQL("select @(count(*))d from archive"
+                " where username=%(LUser)s and %(LServer)H")) of
+		{selected, [{Res}]} ->
+			case Res of
+				0 -> true;
+				_ -> false
+			end;
+		_ -> false
+	end.
+
+is_empty_for_room(LServer, LName, LHost) ->
+    LUser = jid:encode({LName, LHost, <<>>}),
+    is_empty_for_user(LUser, LServer).
+
 %%%===================================================================
 %%% Internal functions
 %%%===================================================================
diff --git a/src/mod_muc.erl b/src/mod_muc.erl
index 29474e511..ae3c6f9f7 100644
--- a/src/mod_muc.erl
+++ b/src/mod_muc.erl
@@ -65,7 +65,8 @@
 	 iq_set_register_info/5,
 	 count_online_rooms_by_user/3,
 	 get_online_rooms_by_user/3,
-	 can_use_nick/4]).
+	 can_use_nick/4,
+	 check_create_room/4]).
 
 -export([init/1, handle_call/3, handle_cast/2,
 	 handle_info/2, terminate/2, code_change/3,
@@ -112,10 +113,14 @@
 %% API
 %%====================================================================
 start(Host, Opts) ->
+    ejabberd_hooks:add(check_create_room, Host, ?MODULE,
+               check_create_room, 50),
     gen_mod:start_child(?MODULE, Host, Opts).
 
 stop(Host) ->
     Rooms = shutdown_rooms(Host),
+    ejabberd_hooks:delete(check_create_room, Host, ?MODULE,
+               check_create_room, 50),
     gen_mod:stop_child(?MODULE, Host),
     {wait, Rooms}.
 
@@ -442,7 +447,9 @@ do_route1(Host, ServerHost, Access, HistorySize, RoomShaper,
 		true ->
 		    case check_user_can_create_room(
 			   ServerHost, AccessCreate, From, Room) and
-			check_create_roomid(ServerHost, Room) of
+			ejabberd_hooks:run_fold(check_create_room,
+					ServerHost, true,
+					[ServerHost, Room, Host]) of
 			true ->
 			    {ok, Pid} = start_new_room(
 					  Host, ServerHost, Access,
@@ -611,9 +618,10 @@ check_user_can_create_room(ServerHost, AccessCreate,
       _ -> false
     end.
 
-check_create_roomid(ServerHost, RoomID) ->
+check_create_room(Acc, ServerHost, RoomID, _Host) ->
     Max = gen_mod:get_module_opt(ServerHost, ?MODULE, max_room_id),
     Regexp = gen_mod:get_module_opt(ServerHost, ?MODULE, regexp_room_id),
+    Acc and
     (byte_size(RoomID) =< Max) and
     (re:run(RoomID, Regexp, [unicode, {capture, none}]) == match).
 
diff --git a/src/mod_muc_admin.erl b/src/mod_muc_admin.erl
index 0dac45e8b..494a4ef3f 100644
--- a/src/mod_muc_admin.erl
+++ b/src/mod_muc_admin.erl
@@ -34,6 +34,7 @@
 	 create_room_with_opts/4, create_room/3, destroy_room/2,
 	 create_rooms_file/1, destroy_rooms_file/1,
 	 rooms_unused_list/2, rooms_unused_destroy/2,
+	 rooms_empty_list/1, rooms_empty_destroy/1,
 	 get_user_rooms/2, get_room_occupants/2,
 	 get_room_occupants_number/2, send_direct_invitation/5,
 	 change_room_option/4, get_room_options/2,
@@ -194,6 +195,25 @@ get_commands_spec() ->
 		       args = [{host, binary}, {days, integer}],
 		       result = {rooms, {list, {room, string}}}},
 
+     #ejabberd_commands{name = rooms_empty_list, tags = [muc],
+		       desc = "List the rooms that have no messages in archive",
+		       module = ?MODULE, function = rooms_empty_list,
+		       args_desc = ["Server host"],
+		       args_example = ["example.com"],
+		       result_desc = "List of empty rooms",
+		       result_example = ["room1@muc.example.com", "room2@muc.example.com"],
+		       args = [{host, binary}],
+		       result = {rooms, {list, {room, string}}}},
+     #ejabberd_commands{name = rooms_empty_destroy, tags = [muc],
+		       desc = "Destroy the rooms that have no messages in archive",
+		       module = ?MODULE, function = rooms_empty_destroy,
+		       args_desc = ["Server host"],
+		       args_example = ["example.com"],
+		       result_desc = "List of empty rooms that have been destroyed",
+		       result_example = ["room1@muc.example.com", "room2@muc.example.com"],
+		       args = [{host, binary}],
+		       result = {rooms, {list, {room, string}}}},
+
      #ejabberd_commands{name = get_user_rooms, tags = [muc],
 			desc = "Get the list of rooms where this user is occupant",
 			module = ?MODULE, function = get_user_rooms,
@@ -718,35 +738,41 @@ create_rooms_file(Filename) ->
 	ok.
 
 
-%%----------------------------
-%% List/Delete Unused Rooms
-%%----------------------------
+%%---------------------------------
+%% List/Delete Unused/Empty Rooms
+%%---------------------------------
 
 %%---------------
 %% Control
 
 rooms_unused_list(ServerHost, Days) ->
-    rooms_unused_report(list, ServerHost, Days).
+    rooms_report(unused, list, ServerHost, Days).
 rooms_unused_destroy(ServerHost, Days) ->
-    rooms_unused_report(destroy, ServerHost, Days).
+    rooms_report(unused, destroy, ServerHost, Days).
 
-rooms_unused_report(Action, ServerHost, Days) ->
-    {NA, NP, RP} = muc_unused(Action, ServerHost, Days),
-    io:format("Unused rooms: ~p out of ~p~n", [NP, NA]),
+rooms_empty_list(ServerHost) ->
+    rooms_report(empty, list, ServerHost, 0).
+rooms_empty_destroy(ServerHost) ->
+    rooms_report(empty, destroy, ServerHost, 0).
+
+
+rooms_report(Method, Action, ServerHost, Days) ->
+    {NA, NP, RP} = muc_unused(Method, Action, ServerHost, Days),
+    io:format("rooms ~s: ~p out of ~p~n", [Method, NP, NA]),
     [<<R/binary, "@", H/binary>> || {R, H, _P} <- RP].
 
-muc_unused(Action, ServerHost, Last_allowed) ->
+muc_unused(Method, Action, ServerHost, Last_allowed) ->
     %% Get all required info about all existing rooms
     Rooms_all = get_rooms(ServerHost),
 
     %% Decide which ones pass the requirements
-    Rooms_pass = decide_rooms(Rooms_all, ServerHost, Last_allowed),
+    Rooms_pass = decide_rooms(Method, Rooms_all, ServerHost, Last_allowed),
 
     Num_rooms_all = length(Rooms_all),
     Num_rooms_pass = length(Rooms_pass),
 
     %% Perform the desired action for matching rooms
-    act_on_rooms(Action, Rooms_pass, ServerHost),
+    act_on_rooms(Method, Action, Rooms_pass, ServerHost),
 
     {Num_rooms_all, Num_rooms_pass, Rooms_pass}.
 
@@ -771,11 +797,11 @@ get_room_state(Room_pid) ->
 %%---------------
 %% Decide
 
-decide_rooms(Rooms, ServerHost, Last_allowed) ->
-    Decide = fun(R) -> decide_room(R, ServerHost, Last_allowed) end,
+decide_rooms(Method, Rooms, ServerHost, Last_allowed) ->
+    Decide = fun(R) -> decide_room(Method, R, ServerHost, Last_allowed) end,
     lists:filter(Decide, Rooms).
 
-decide_room({_Room_name, _Host, Room_pid}, ServerHost, Last_allowed) ->
+decide_room(unused, {_Room_name, _Host, Room_pid}, ServerHost, Last_allowed) ->
     C = get_room_config(Room_pid),
     Persistent = C#config.persistent,
 
@@ -811,6 +837,13 @@ decide_room({_Room_name, _Host, Room_pid}, ServerHost, Last_allowed) ->
 	    true;
 	_ ->
 	    false
+    end;
+decide_room(empty, {Room_name, Host, _Room_pid}, ServerHost, _Last_allowed) ->
+    case gen_mod:is_loaded(ServerHost, mod_mam) of
+        true ->
+        mod_mam:is_empty_for_room(ServerHost, Room_name, Host);
+        _ ->
+        false
     end.
 
 seconds_to_days(S) ->
@@ -819,7 +852,7 @@ seconds_to_days(S) ->
 %%---------------
 %% Act
 
-act_on_rooms(Action, Rooms, ServerHost) ->
+act_on_rooms(Method, Action, Rooms, ServerHost) ->
     ServerHosts = [ {A, find_host(A)} || A <- ejabberd_config:get_myhosts() ],
     Delete = fun({_N, H, _Pid} = Room) ->
 		     SH = case ServerHost of
@@ -827,7 +860,7 @@ act_on_rooms(Action, Rooms, ServerHost) ->
 			      O -> O
 			  end,
 
-		     act_on_room(Action, Room, SH)
+		     act_on_room(Method, Action, Room, SH)
 	     end,
     lists:foreach(Delete, Rooms).
 
@@ -835,13 +868,15 @@ find_serverhost(Host, ServerHosts) ->
     {value, {ServerHost, Host}} = lists:keysearch(Host, 2, ServerHosts),
     ServerHost.
 
-act_on_room(destroy, {N, H, Pid}, SH) ->
+act_on_room(Method, destroy, {N, H, Pid}, SH) ->
+    Message = iolist_to_binary(io_lib:format(
+        <<"Room destroyed by rooms_~s_destroy.">>, [Method])),
     p1_fsm:send_all_state_event(
-      Pid, {destroy, <<"Room destroyed by rooms_unused_destroy.">>}),
+      Pid, {destroy, Message}),
     mod_muc:room_destroyed(H, N, Pid, SH),
     mod_muc:forget_room(SH, H, N);
 
-act_on_room(list, _, _) ->
+act_on_room(_Method, list, _, _) ->
     ok.