generalise binding code somewhat to mostly abstract away the source kind

- not completely, since that would require substantial changes, but
  enough to make the code more pleasing to the eye

3 files changed, 21 insertions, 18 deletions

diff --git a/src/rabbit_binding.erl b/src/rabbit_binding.erl
index 78403b81a8..0199a35469 100644
--- a/src/rabbit_binding.erl
+++ b/src/rabbit_binding.erl
@@ -67,11 +67,12 @@
 -spec(remove/2 :: (rabbit_types:binding(), inner_fun()) ->
                        bind_res() | rabbit_types:error('binding_not_found')).
 -spec(list/1 :: (rabbit_types:vhost()) -> bindings()).
--spec(list_for_source/1 :: (rabbit_exchange:name()) -> bindings()).
--spec(list_for_destination/1 :: (rabbit_types:binding_destination()) ->
-                                     bindings()).
+-spec(list_for_source/1 ::
+        (rabbit_types:binding_source()) -> bindings()).
+-spec(list_for_destination/1 ::
+        (rabbit_types:binding_destination()) -> bindings()).
 -spec(list_for_source_and_destination/2 ::
-        (rabbit_exchange:name(), rabbit_types:binding_destination()) ->
+        (rabbit_types:binding_source(), rabbit_types:binding_destination()) ->
                                                 bindings()).
 -spec(info_keys/0 :: () -> [rabbit_types:info_key()]).
 -spec(info/1 :: (rabbit_types:binding()) -> [rabbit_types:info()]).
@@ -80,8 +81,8 @@
 -spec(info_all/1 :: (rabbit_types:vhost()) -> [[rabbit_types:info()]]).
 -spec(info_all/2 ::(rabbit_types:vhost(), [rabbit_types:info_key()])
                     -> [[rabbit_types:info()]]).
--spec(has_for_source/1 :: (rabbit_exchange:name()) -> boolean()).
--spec(remove_for_source/1 :: (rabbit_exchange:name()) -> bindings()).
+-spec(has_for_source/1 :: (rabbit_types:binding_source()) -> boolean()).
+-spec(remove_for_source/1 :: (rabbit_types:binding_source()) -> bindings()).
 -spec(remove_for_destination/1 ::
         (rabbit_types:binding_destination()) -> fun (() -> any())).
 -spec(remove_transient_for_destination/1 ::
@@ -282,12 +283,10 @@ sync_binding(Binding, Durable, Fun) ->
     ok.
 
 call_with_source_and_destination(SrcName, DstName, Fun) ->
-    DstTable = case DstName#resource.kind of
-                   queue    -> rabbit_queue;
-                   exchange -> rabbit_exchange
-               end,
+    SrcTable = table_for_resource(SrcName),
+    DstTable = table_for_resource(DstName),
     rabbit_misc:execute_mnesia_transaction(
-      fun () -> case {mnesia:read({rabbit_exchange, SrcName}),
+      fun () -> case {mnesia:read({SrcTable, SrcName}),
                       mnesia:read({DstTable, DstName})} of
                     {[Src], [Dst]} -> Fun(Src, Dst);
                     {[],    [_]  } -> {error, source_not_found};
@@ -296,6 +295,9 @@ call_with_source_and_destination(SrcName, DstName, Fun) ->
                 end
       end).
 
+table_for_resource(#resource{kind = exchange}) -> rabbit_exchange;
+table_for_resource(#resource{kind = queue})    -> rabbit_queue.
+
 %% Used with atoms from records; e.g., the type is expected to exist.
 type_to_module(T) ->
     {ok, Module} = rabbit_exchange_type_registry:lookup_module(T),
diff --git a/src/rabbit_router.erl b/src/rabbit_router.erl
index a2fbd3cab2..6f91633ecb 100644
--- a/src/rabbit_router.erl
+++ b/src/rabbit_router.erl
@@ -48,11 +48,11 @@
 
 -spec(deliver/2 ::
         (qpids(), rabbit_types:delivery()) -> {routing_result(), qpids()}).
--spec(match_bindings/2 :: (rabbit_exchange:name(),
+-spec(match_bindings/2 :: (rabbit_types:binding_source(),
                            fun ((rabbit_types:binding()) -> boolean())) ->
     match_result()).
--spec(match_routing_key/2 :: (rabbit_exchange:name(), routing_key() | '_') ->
-                                  match_result()).
+-spec(match_routing_key/2 :: (rabbit_types:binding_source(),
+                              routing_key() | '_') -> match_result()).
 
 -endif.
 
@@ -83,7 +83,7 @@ deliver(QPids, Delivery) ->
                    {Routed, Handled}).
 
 %% TODO: Maybe this should be handled by a cursor instead.
-%% TODO: This causes a full scan for each entry with the same exchange
+%% TODO: This causes a full scan for each entry with the same source
 match_bindings(SrcName, Match) ->
     Query = qlc:q([DestinationName ||
                       #route{binding = Binding = #binding{
diff --git a/src/rabbit_types.erl b/src/rabbit_types.erl
index 603c45bd1d..b971a63f72 100644
--- a/src/rabbit_types.erl
+++ b/src/rabbit_types.erl
@@ -39,7 +39,8 @@
               delivery/0, content/0, decoded_content/0, undecoded_content/0,
               unencoded_content/0, encoded_content/0, vhost/0, ctag/0,
               amqp_error/0, r/1, r2/2, r3/3, listener/0,
-              binding/0, binding_destination/0, amqqueue/0, exchange/0,
+              binding/0, binding_source/0, binding_destination/0,
+              amqqueue/0, exchange/0,
               connection/0, protocol/0, user/0, ok/1, error/1, ok_or_error/1,
               ok_or_error2/2, ok_pid_or_error/0, channel_exit/0,
               connection_exit/0]).
@@ -114,8 +115,8 @@
                 host     :: rabbit_networking:hostname(),
                 port     :: rabbit_networking:ip_port()}).
 
--type(binding_destination() ::
-        rabbit_amqqueue:name() | rabbit_exchange:name()).
+-type(binding_source() :: rabbit_exchange:name()).
+-type(binding_destination() :: rabbit_amqqueue:name() | rabbit_exchange:name()).
 
 -type(binding() ::
       #binding{source      :: rabbit_exchange:name(),