Switch (back) to using the type name atom in #exchange, rather than

the module.  This is to restore the indirection between types and
their implementation.  Note also that we no longer need the reverse
mapping.

4 files changed, 37 insertions, 32 deletions

diff --git a/src/rabbit_access_control.erl b/src/rabbit_access_control.erl
index daf6f5af40..6ff7a1046c 100644
--- a/src/rabbit_access_control.erl
+++ b/src/rabbit_access_control.erl
@@ -242,12 +242,12 @@ add_vhost(VHostPath) ->
                              rabbit_misc:r(VHostPath, exchange, Name),
                              Type, true, false, []) ||
                               {Name,Type} <-
-                                  [{<<"">>,           rabbit_exchange_type_direct},
-                                   {<<"amq.direct">>, rabbit_exchange_type_direct},
-                                   {<<"amq.topic">>,  rabbit_exchange_type_topic},
-                                   {<<"amq.match">>,  rabbit_exchange_type_headers}, %% per 0-9-1 pdf
-                                   {<<"amq.headers">>,  rabbit_exchange_type_headers}, %% per 0-9-1 xml
-                                   {<<"amq.fanout">>, rabbit_exchange_type_fanout}]],
+                                  [{<<"">>,           direct},
+                                   {<<"amq.direct">>, direct},
+                                   {<<"amq.topic">>,  topic},
+                                   {<<"amq.match">>,  headers}, %% per 0-9-1 pdf
+                                   {<<"amq.headers">>,  headers}, %% per 0-9-1 xml
+                                   {<<"amq.fanout">>, fanout}]],
                           ok;
                       [_] ->
                           mnesia:abort({vhost_already_exists, VHostPath})
diff --git a/src/rabbit_error_logger.erl b/src/rabbit_error_logger.erl
index 9651ae12ac..b9bd71b78d 100644
--- a/src/rabbit_error_logger.erl
+++ b/src/rabbit_error_logger.erl
@@ -48,7 +48,7 @@ boot() ->
 init([DefaultVHost]) ->
     #exchange{} = rabbit_exchange:declare(
                     rabbit_misc:r(DefaultVHost, exchange, ?LOG_EXCH_NAME),
-                    rabbit_exchange_type_topic, true, false, []),
+                    topic, true, false, []),
     {ok, #resource{virtual_host = DefaultVHost,
                    kind = exchange,
                    name = ?LOG_EXCH_NAME}}.
diff --git a/src/rabbit_exchange.erl b/src/rabbit_exchange.erl
index 05bef73af2..d004a279f8 100644
--- a/src/rabbit_exchange.erl
+++ b/src/rabbit_exchange.erl
@@ -123,7 +123,7 @@ recover_with_bindings([B = #binding{exchange_name = N} | Rest],
   when N =:= Name ->
     recover_with_bindings(Rest, Xs, [B | Bindings]);
 recover_with_bindings(Bs, [X = #exchange{ type = Type } | Xs], Bindings) ->
-    Type:recover(X, Bindings),
+    (type_to_module(Type)):recover(X, Bindings),
     recover_with_bindings(Bs, Xs, []);
 recover_with_bindings([], [], []) ->
     ok.
@@ -137,7 +137,8 @@ declare(ExchangeName, Type, Durable, AutoDelete, Args) ->
     %% We want to upset things if it isn't ok; this is different from
     %% the other hooks invocations, where we tend to ignore the return
     %% value.
-    ok = Type:validate(Exchange),
+    TypeModule = (type_to_module(Type)),
+    ok = TypeModule:validate(Exchange),
     case rabbit_misc:execute_mnesia_transaction(
            fun () ->
                    case mnesia:wread({rabbit_exchange, ExchangeName}) of
@@ -154,13 +155,13 @@ declare(ExchangeName, Type, Durable, AutoDelete, Args) ->
                            {existing, ExistingX}
                    end
            end) of
-        {new, X}      -> Type:create(X),
+        {new, X}      -> TypeModule:create(X),
                          X;
         {existing, X} -> X;
         Err           -> Err
     end.
 
-typename_to_plugin_module(T) ->
+type_to_module(T) ->
     case rabbit_exchange_type:lookup_module(T) of
         {ok, Module}       -> Module;
         {error, not_found} -> rabbit_misc:protocol_error(
@@ -168,12 +169,9 @@ typename_to_plugin_module(T) ->
                                 "invalid exchange type '~s'", [T])
     end.
 
-plugin_module_to_typename(M) ->
-    {ok, TypeName} = rabbit_exchange_type:lookup_name(M),
-    TypeName.
-
-check_type(T) ->
-    Module = typename_to_plugin_module(T),
+check_type(TypeBin) ->
+    T = rabbit_exchange_type:binary_to_type(TypeBin),
+    Module = type_to_module(T),
     case catch Module:description() of
         {'EXIT', {undef, [{_, description, []} | _]}} ->
             rabbit_misc:protocol_error(
@@ -182,7 +180,7 @@ check_type(T) ->
             rabbit_misc:protocol_error(
               command_invalid, "problem loading exchange type '~s'", [T]);
         _ ->
-            Module
+            T
     end.
 
 assert_type(#exchange{ type = ActualType }, RequiredType)
@@ -192,8 +190,8 @@ assert_type(#exchange{ name = Name, type = ActualType }, RequiredType) ->
     rabbit_misc:protocol_error(
       not_allowed, "cannot redeclare ~s of type '~s' with type '~s'",
       [rabbit_misc:rs(Name),
-       plugin_module_to_typename(ActualType),
-       plugin_module_to_typename(RequiredType)]).
+       ActualType,
+       RequiredType]).
 
 lookup(Name) ->
     rabbit_misc:dirty_read({rabbit_exchange, Name}).
@@ -217,7 +215,7 @@ map(VHostPath, F) ->
 infos(Items, X) -> [{Item, i(Item, X)} || Item <- Items].
 
 i(name,        #exchange{name        = Name})       -> Name;
-i(type,        #exchange{type        = Type})       -> plugin_module_to_typename(Type);
+i(type,        #exchange{type        = Type})       -> Type;
 i(durable,     #exchange{durable     = Durable})    -> Durable;
 i(auto_delete, #exchange{auto_delete = AutoDelete}) -> AutoDelete;
 i(arguments,   #exchange{arguments   = Arguments})  -> Arguments;
@@ -235,7 +233,7 @@ publish(X, Delivery) ->
     publish(X, [], Delivery).
 
 publish(X = #exchange{type = Type}, Seen, Delivery) ->
-    case Type:publish(X, Delivery) of
+    case (type_to_module(Type)):publish(X, Delivery) of
         {_, []} = R ->
             #exchange{name = XName, arguments = Args} = X,
             case rabbit_misc:r_arg(XName, exchange, Args,
@@ -306,9 +304,9 @@ delete_queue_bindings(QueueName, FwdDeleteFun) ->
                               none, [], []),
     fun () ->
             lists:foreach(fun ({{deleted, X = #exchange{ type = Type}}, Bs}) ->
-                                  Type:delete(X, Bs);
+                                  (type_to_module(Type)):delete(X, Bs);
                               ({{_, X = #exchange{ type = Type }}, Bs}) ->
-                                  [Type:delete_binding(X, B) || B <- Bs]
+                                  [(type_to_module(Type)):delete_binding(X, B) || B <- Bs]
                           end, BindingsWithExchanges)
     end.
 
@@ -392,7 +390,7 @@ add_binding(ExchangeName, QueueName, RoutingKey, Arguments) ->
                    end
            end) of
         {new, Exchange = #exchange{ type = Type }, Binding} ->
-            Type:add_binding(Exchange, Binding);
+            (type_to_module(Type)):add_binding(Exchange, Binding);
         {existing, _, _} ->
             ok;
         Err = {error, _}  ->
@@ -412,11 +410,12 @@ delete_binding(ExchangeName, QueueName, RoutingKey, Arguments) ->
                    end
            end) of
         {{deleted, X = #exchange{ type = Type }}, B} ->
-            Type:delete_binding(X, B),
-            Type:delete(X),
+            Module = (type_to_module(Type)),
+            Module:delete_binding(X, B),
+            Module:delete(X),
             ok;
         {{no_delete, X = #exchange{ type = Type }}, B} ->
-            Type:delete_binding(X, B),
+            (type_to_module(Type)):delete_binding(X, B),
             ok;
         Err ->
             Err
@@ -495,7 +494,7 @@ delete(ExchangeName, IfUnused) ->
           end,
     case call_with_exchange(ExchangeName, Fun) of
         {deleted, X = #exchange{ type = Type }, Bs} ->
-            Type:delete(X, Bs),
+            (type_to_module(Type)):delete(X, Bs),
             ok;
         Err ->
             Err
diff --git a/src/rabbit_exchange_type.erl b/src/rabbit_exchange_type.erl
index 58dcfbb6a2..9d5fb20229 100644
--- a/src/rabbit_exchange_type.erl
+++ b/src/rabbit_exchange_type.erl
@@ -38,10 +38,12 @@
 -export([init/1, handle_call/3, handle_cast/2, handle_info/2,
          terminate/2, code_change/3]).
 
--export([register/2, lookup_module/1, lookup_name/1]).
+-export([register/2, binary_to_type/1, lookup_module/1, lookup_name/1]).
 
 -define(SERVER, ?MODULE).
 
+%% TODO specs
+
 %%---------------------------------------------------------------------------
 
 start_link() ->
@@ -52,7 +54,10 @@ start_link() ->
 register(TypeName, ModuleName) ->
     gen_server:call(?SERVER, {register, TypeName, ModuleName}).
 
-lookup_module(T) when is_binary(T) ->
+binary_to_type(TypeBin) when is_binary(TypeBin) ->
+    list_to_atom(binary_to_list(TypeBin)).
+
+lookup_module(T) when is_atom(T) ->
     case ets:lookup(rabbit_exchange_type_modules, T) of
         [{_, Module}] ->
             {ok, Module};
@@ -68,7 +73,8 @@ lookup_name(M) when is_atom(M) ->
 
 internal_register(TypeName, ModuleName)
   when is_binary(TypeName), is_atom(ModuleName) ->
-    true = ets:insert(rabbit_exchange_type_modules, {TypeName, ModuleName}),
+    true = ets:insert(rabbit_exchange_type_modules,
+                      {binary_to_type(TypeName), ModuleName}),
     true = ets:insert(rabbit_exchange_type_names, {ModuleName, TypeName}),
     ok.