Fix management extension enable/disable handling

When notifying about 'enabled' plugins, limit to explicitly given.
When handling 'disabled' plugins, call the event handler(s)
synchronously (while we still have loaded modules) prior to stopping
and unloading any apps.

3 files changed, 28 insertions, 10 deletions

diff --git a/src/rabbit.erl b/src/rabbit.erl
index 6c08520fd2..8a6826162f 100644
--- a/src/rabbit.erl
+++ b/src/rabbit.erl
@@ -210,6 +210,7 @@
 %% this really should be an abstract type
 -type(log_location() :: 'tty' | 'undefined' | file:filename()).
 -type(param() :: atom()).
+-type(app_name() :: atom()).
 
 -spec(start/0 :: () -> 'ok').
 -spec(boot/0 :: () -> 'ok').
@@ -241,6 +242,8 @@
 -spec(maybe_insert_default_data/0 :: () -> 'ok').
 -spec(boot_delegate/0 :: () -> 'ok').
 -spec(recover/0 :: () -> 'ok').
+-spec(start_apps/1 :: ([app_name()]) -> 'ok').
+-spec(stop_apps/1 :: ([app_name()]) -> 'ok').
 
 -endif.
 
@@ -350,8 +353,7 @@ start_apps(Apps) ->
         _         -> ok
     end,
     ok = app_utils:start_applications(StartupApps,
-                                      handle_app_error(could_not_start)),
-    StartupApps.
+                                      handle_app_error(could_not_start)).
 
 start_it(StartFun) ->
     Marker = spawn_link(fun() -> receive stop -> ok end end),
diff --git a/src/rabbit_event.erl b/src/rabbit_event.erl
index b867223b50..8872690092 100644
--- a/src/rabbit_event.erl
+++ b/src/rabbit_event.erl
@@ -23,6 +23,7 @@
          ensure_stats_timer/3, stop_stats_timer/2, reset_stats_timer/2]).
 -export([stats_level/2, if_enabled/3]).
 -export([notify/2, notify/3, notify_if/3]).
+-export([sync_notify/2, sync_notify/3]).
 
 %%----------------------------------------------------------------------------
 
@@ -61,6 +62,9 @@
 -spec(notify/2 :: (event_type(), event_props()) -> 'ok').
 -spec(notify/3 :: (event_type(), event_props(), reference() | 'none') -> 'ok').
 -spec(notify_if/3 :: (boolean(), event_type(), event_props()) -> 'ok').
+-spec(sync_notify/2 :: (event_type(), event_props()) -> 'ok').
+-spec(sync_notify/3 :: (event_type(), event_props(),
+                        reference() | 'none') -> 'ok').
 
 -endif.
 
@@ -145,7 +149,19 @@ notify_if(false, _Type, _Props) -> ok.
 notify(Type, Props) -> notify(Type, Props, none).
 
 notify(Type, Props, Ref) ->
-    gen_event:notify(?MODULE, #event{type      = Type,
-                                     props     = Props,
-                                     reference = Ref,
-                                     timestamp = os:timestamp()}).
+    do_notify(notify, #event{type      = Type,
+                             props     = Props,
+                             reference = Ref,
+                             timestamp = os:timestamp()}).
+
+sync_notify(Type, Props) -> sync_notify(Type, Props, none).
+
+sync_notify(Type, Props, Ref) ->
+    do_notify(sync_notify, #event{ type      = Type,
+                                   props     = Props,
+                                   reference = Ref,
+                                   timestamp = os:timestamp()}).
+
+do_notify(F, Event) ->
+    apply(gen_event, F, [?MODULE, Event]).
+
diff --git a/src/rabbit_plugins.erl b/src/rabbit_plugins.erl
index cc65c5699b..767e4adc33 100644
--- a/src/rabbit_plugins.erl
+++ b/src/rabbit_plugins.erl
@@ -40,15 +40,15 @@
 
 enable(Plugins) ->
     prepare_plugins(Plugins),
-    Diff = rabbit:start_apps(Plugins),
-    ok = rabbit_event:notify(plugins_changed, [{enabled, Diff}]).
+    rabbit:start_apps(Plugins),
+    ok = rabbit_event:notify(plugins_changed, [{enabled, Plugins}]).
 
 disable(Plugins) ->
     RunningApps = rabbit_misc:which_applications(),
     ToDisable = [P || P <- Plugins,
                       proplists:is_defined(P, RunningApps)],
-    rabbit:stop_apps(ToDisable),
-    ok = rabbit_event:notify(plugins_changed, [{disabled, ToDisable}]).
+    ok = rabbit_event:sync_notify(plugins_changed, [{disabled, ToDisable}]),
+    rabbit:stop_apps(ToDisable).
 
 %% @doc Prepares the file system and installs all enabled plugins.
 setup() ->