From af8bc8ee324a22a9f3938e9bcd30a3dca7909620 Mon Sep 17 00:00:00 2001
From: EMQ-YangM <yangm@emqx.io>
Date: Thu, 17 Feb 2022 18:15:19 +0800
Subject: [PATCH] fix(emqx_rule_metrics):  add a function for code hot upgrade

---
 apps/emqx_rule_engine/src/emqx_rule_metrics.erl | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/apps/emqx_rule_engine/src/emqx_rule_metrics.erl b/apps/emqx_rule_engine/src/emqx_rule_metrics.erl
index 0da6b1197..0dfec930e 100644
--- a/apps/emqx_rule_engine/src/emqx_rule_metrics.erl
+++ b/apps/emqx_rule_engine/src/emqx_rule_metrics.erl
@@ -340,7 +340,7 @@ code_change({down, _Vsn}, State = #state{metric_ids = MIDs}, [Vsn]) ->
                         Exception = get_actions_exception(Id),
                         Retry = get_actions_retry(Id),
                         ok = delete_counters(Id),
-                        ok = create_counters(Id, 7),
+                        ok = create_counters(Id, max_counters_size_old()),
                         inc_rules_matched(Id, Passed),
                         inc_actions_taken(Id, Take),
                         inc_actions_success(Id, Success),
@@ -464,6 +464,9 @@ precision(Float, N) ->
 %% Metrics Definitions
 %%------------------------------------------------------------------------------
 
+%% for code hot upgrade
+max_counters_size_old() -> 7.
+
 max_counters_size() -> 11.
 
 metrics_idx('rules.matched') ->       1;