Ignore missing exchange decorators

2 files changed, 17 insertions, 4 deletions

diff --git a/src/rabbit_exchange.erl b/src/rabbit_exchange.erl
index 6d111b8316..e7847673b4 100644
--- a/src/rabbit_exchange.erl
+++ b/src/rabbit_exchange.erl
@@ -113,8 +113,17 @@ recover() ->
                    callback(X, create, map_create_tx(Tx), [X])
            end,
            rabbit_durable_exchange),
+    report_missing_decorators(Xs),
     [XName || #exchange{name = XName} <- Xs].
 
+report_missing_decorators(Xs) ->
+    Mods = lists:usort(lists:append([rabbit_exchange_decorator:select(raw, D) ||
+                                     #exchange{decorators = D} <- Xs])),
+    case [M || M <- Mods, code:which(M) =:= non_existing] of
+        [] -> ok;
+        M  -> rabbit_log:warning("Missing exchange decorators: ~p~n", [M])
+    end.
+
 callback(X = #exchange{type       = XType,
                        decorators = Decorators}, Fun, Serial0, Args) ->
     Serial = if is_function(Serial0) -> Serial0;
diff --git a/src/rabbit_exchange_decorator.erl b/src/rabbit_exchange_decorator.erl
index 3bc9de1ead..19cbf92f80 100644
--- a/src/rabbit_exchange_decorator.erl
+++ b/src/rabbit_exchange_decorator.erl
@@ -84,11 +84,13 @@ behaviour_info(_Other) ->
 
 %%----------------------------------------------------------------------------
 
-list() -> [M || {_, M} <- rabbit_registry:lookup_all(exchange_decorator)].
-
 %% select a subset of active decorators
-select(all,   {Route, NoRoute})  -> Route ++ NoRoute;
-select(route, {Route, _NoRoute}) -> Route.
+select(all,   {Route, NoRoute})  -> filter(Route ++ NoRoute);
+select(route, {Route, _NoRoute}) -> filter(Route);
+select(raw,   {Route, NoRoute})  -> Route ++ NoRoute.
+
+filter(Modules) ->
+    [M || M <- Modules, code:which(M) =/= non_existing].
 
 set(X) ->
     X#exchange{
@@ -99,5 +101,7 @@ set(X) ->
                              cons_if_eq(noroute, Callbacks, D, NoRoute)}
                     end, {[], []}, list())}.
 
+list() -> [M || {_, M} <- rabbit_registry:lookup_all(exchange_decorator)].
+
 cons_if_eq(Select,  Select, Item,  List) -> [Item | List];
 cons_if_eq(_Select, _Other, _Item, List) -> List.