Clear temporary runtime exchange parameters on boot

This makes sure that values that were set right before
node failure or restart are not retained.

Author: michaelklishin

src/rabbit_exchange.erl

@@ -171,7 +171,7 @@ declare(XName, Type, Durable, AutoDelete, Internal, Args) ->
     %%
     %% See rabbitmq/rabbitmq-federation#7.
     case rabbit_runtime_parameters:lookup(XName#resource.virtual_host,
-                                          <<"exchange-delete-in-progress">>,
+                                          ?EXCHANGE_DELETE_IN_PROGRESS_COMPONENT,
                                           XName#resource.name) of
         not_found ->
             rabbit_misc:execute_mnesia_transaction(
@@ -446,7 +446,7 @@ delete(XName, IfUnused) ->
         %%
         %% see rabbitmq/rabbitmq-federation#7
         rabbit_runtime_parameters:set(XName#resource.virtual_host,
-                                      <<"exchange-delete-in-progress">>,
+                                      ?EXCHANGE_DELETE_IN_PROGRESS_COMPONENT,
                                       XName#resource.name, true, none),
         call_with_exchange(
           XName,
@@ -462,7 +462,7 @@ delete(XName, IfUnused) ->
           end)
     after
         rabbit_runtime_parameters:clear(XName#resource.virtual_host,
-                                        <<"exchange-delete-in-progress">>,
+                                        ?EXCHANGE_DELETE_IN_PROGRESS_COMPONENT,
                                         XName#resource.name)
     end.
 

src/rabbit_exchange_parameters.erl

@@ -18,9 +18,13 @@
 
 -behaviour(rabbit_runtime_parameter).
 
+-include("rabbit.hrl").
+
 -export([register/0]).
 -export([validate/5, notify/4, notify_clear/3]).
 
+-import(rabbit_misc, [pget/2]).
+
 -rabbit_boot_step({?MODULE,
                    [{description, "exchange parameters"},
                     {mfa, {rabbit_exchange_parameters, register, []}},
@@ -29,13 +33,17 @@
 
 register() ->
     rabbit_registry:register(runtime_parameter,
-                             <<"exchange-delete-in-progress">>, ?MODULE).
+                             ?EXCHANGE_DELETE_IN_PROGRESS_COMPONENT, ?MODULE),
+    %% ensure there are no leftovers from before node restart/crash
+    rabbit_runtime_parameters:clear_component(
+      ?EXCHANGE_DELETE_IN_PROGRESS_COMPONENT),
+    ok.
 
-validate(_VHost, <<"exchange-delete-in-progress">>, _Name, _Term, _User) ->
+validate(_VHost, ?EXCHANGE_DELETE_IN_PROGRESS_COMPONENT, _Name, _Term, _User) ->
     ok.
 
-notify(_VHost, <<"exchange-delete-in-progress">>, _Name, _Term) ->
+notify(_VHost, ?EXCHANGE_DELETE_IN_PROGRESS_COMPONENT, _Name, _Term) ->
     ok.
 
-notify_clear(_VHost, <<"exchange-delete-in-progress">>, _Name) ->
+notify_clear(_VHost, ?EXCHANGE_DELETE_IN_PROGRESS_COMPONENT, _Name) ->
     ok.

src/rabbit_runtime_parameters.erl

@@ -51,7 +51,7 @@
 
 -export([parse_set/5, set/5, set_any/5, clear/3, clear_any/3, list/0, list/1,
          list_component/1, list/2, list_formatted/1, list_formatted/3,
-         lookup/3, value/3, value/4, info_keys/0]).
+         lookup/3, value/3, value/4, info_keys/0, clear_component/1]).
 
 -export([set_global/2, value_global/1, value_global/2]).
 
@@ -171,6 +171,17 @@ clear(_, <<"policy">> , _) ->
 clear(VHost, Component, Name) ->
     clear_any(VHost, Component, Name).
 
+clear_component(Component) ->
+    case rabbit_runtime_parameters:list_component(Component) of
+        [] ->
+            ok;
+        Xs ->
+            [rabbit_runtime_parameters:clear(pget(vhost, X),
+                                             pget(component, X),
+                                             pget(name, X))|| X <- Xs],
+            ok
+    end.
+
 clear_any(VHost, Component, Name) ->
     Notify = fun () ->
                      case lookup_component(Component) of