Merge pull request #12216 from rabbitmq/mergify/bp/v4.0.x/pr-12148

Author: the-mikedavis

deps/rabbitmq_prometheus/src/collectors/prometheus_rabbitmq_core_metrics_collector.erl

@@ -640,6 +640,19 @@ get_data(Table, false, VHostsFilter) when Table == channel_exchange_metrics;
         _ ->
             [Result]
     end;
+get_data(ra_metrics = Table, true, _) ->
+    ets:foldl(
+      fun ({#resource{kind = queue}, _, _, _, _, _, _} = Row, Acc) ->
+              %% Metrics for QQ records use the queue resource as the table
+              %% key. The queue name and vhost will be rendered as tags.
+              [Row | Acc];
+          ({ClusterName, _, _, _, _, _, _} = Row, Acc) when is_atom(ClusterName) ->
+              %% Other Ra clusters like Khepri and the stream coordinator use
+              %% the cluster name as the metrics key. Transform this into a
+              %% value that can be rendered as a "raft_cluster" tag.
+              Row1 = setelement(1, Row, #{<<"raft_cluster">> => atom_to_binary(ClusterName, utf8)}),
+              [Row1 | Acc]
+      end, [], Table);
 get_data(exchange_metrics = Table, true, VHostsFilter) when is_map(VHostsFilter)->
     ets:foldl(fun
         ({#resource{kind = exchange, virtual_host = VHost}, _, _, _, _, _} = Row, Acc) when