Merge pull request #474 from rabbitmq/md/aux/machine-version

ra_aux: Expose effective machine version, current term

src/ra_aux.erl

@@ -7,8 +7,10 @@
 
 -export([
          machine_state/1,
+         effective_machine_version/1,
          leader_id/1,
          last_applied/1,
+         current_term/1,
          members_info/1,
          overview/1,
          log_last_index_term/1,
@@ -17,6 +19,7 @@
         ]).
 
 -include("ra.hrl").
+-include("ra_server.hrl").
 
 -opaque internal_state() :: ra_server:state().
 
@@ -26,6 +29,11 @@
 machine_state(State) ->
     maps:get(?FUNCTION_NAME, State).
 
+-spec effective_machine_version(ra_aux:internal_state()) ->
+    ra_machine:version().
+effective_machine_version(#{cfg := Cfg}) ->
+    Cfg#cfg.effective_machine_version.
+
 -spec leader_id(ra_aux:internal_state()) -> undefined | ra_server_id().
 leader_id(State) ->
     maps:get(?FUNCTION_NAME, State).
@@ -34,6 +42,10 @@ leader_id(State) ->
 last_applied(State) ->
     maps:get(?FUNCTION_NAME, State).
 
+-spec current_term(ra_aux:internal_state()) -> ra_term().
+current_term(State) ->
+    maps:get(?FUNCTION_NAME, State).
+
 -spec members_info(ra_aux:internal_state()) -> ra_cluster().
 members_info(State) ->
     ra_server:state_query(?FUNCTION_NAME, State).