Добавлена оперативная и историческая статистика нод и узлов mnesia #22

src/core/core_counters.erl

@@ -0,0 +1,30 @@
+-module(core_counters).
+-export([inc/1, dec/1, get/1, read_and_reset/1]).
+
+-define(TABLE, eventhub_counters).
+
+inc(Key) ->
+  try ets:update_counter(?TABLE, Key, {2, 1})  % позиция 2 — значение
+  catch error:badarg ->
+    ets:insert(?TABLE, {Key, 1})
+  end.
+
+dec(Key) ->
+  try ets:update_counter(?TABLE, Key, {2, -1})
+  catch error:badarg ->
+    ets:insert(?TABLE, {Key, 0})
+  end.
+
+get(Key) ->
+  case ets:lookup(?TABLE, Key) of
+    [{Key, Val}] -> Val;
+    [] -> 0
+  end.
+
+read_and_reset(Key) ->
+  case ets:lookup(?TABLE, Key) of
+    [{Key, Val}] ->
+      ets:insert(?TABLE, {Key, 0}),
+      Val;
+    [] -> 0
+  end.