Make it possible to clear cluster_tags via rabbitmq.conf

Author: michaelklishin

deps/rabbit/src/rabbit.erl

@@ -38,7 +38,7 @@
 
 %%---------------------------------------------------------------------------
 %% Boot steps.
--export([maybe_set_cluster_tags/0, maybe_insert_default_data/0, boot_delegate/0, recover/0,
+-export([update_cluster_tags/0, maybe_insert_default_data/0, boot_delegate/0, recover/0,
          pg_local_amqp_session/0,
          pg_local_amqp_connection/0]).
 
@@ -211,7 +211,7 @@
 
 -rabbit_boot_step({cluster_tags,
                    [{description, "Set cluster tags"},
-                    {mfa,         {?MODULE, maybe_set_cluster_tags, []}},
+                    {mfa,         {?MODULE, update_cluster_tags, []}},
                     {requires,    core_initialized}]}).
 
 -rabbit_boot_step({routing_ready,
@@ -1145,17 +1145,13 @@ pg_local_scope(Prefix) ->
     list_to_atom(io_lib:format("~s_~s", [Prefix, node()])).
 
 
--spec maybe_set_cluster_tags() -> 'ok'.
+-spec update_cluster_tags() -> 'ok'.
 
-maybe_set_cluster_tags() ->
+update_cluster_tags() ->
     Tags = application:get_env(rabbit, cluster_tags, []),
-    case Tags of
-        [] -> ok;
-        Value ->
-            ?LOG_DEBUG("Seeding cluster tags from application environment key...",
+    ?LOG_DEBUG("Seeding cluster tags from application environment key...",
                        #{domain => ?RMQLOG_DOMAIN_GLOBAL}),
-            rabbit_runtime_parameters:set_global(cluster_tags, Value, <<"internal_user">>)
-    end.
+    rabbit_runtime_parameters:set_global(cluster_tags, Tags, <<"internal_user">>).
 
 -spec maybe_insert_default_data() -> 'ok'.