fix(rule_engine_metics): centralized statistics exception

apps/emqx_rule_engine/src/emqx_rule_runtime.erl

@@ -51,23 +51,27 @@ apply_rules([], _Input) ->
 apply_rules([#rule{enabled = false}|More], Input) ->
     apply_rules(More, Input);
 apply_rules([Rule = #rule{id = RuleID}|More], Input) ->
-    ok = emqx_rule_metrics:inc_rules_matched(RuleID),
     try apply_rule_discard_result(Rule, Input)
     catch
         %% ignore the errors if select or match failed
         _:{select_and_transform_error, Error} ->
+            emqx_rule_metrics:inc_rules_exception(RuleId),
             ?LOG(warning, "SELECT clause exception for ~s failed: ~p",
                  [RuleID, Error]);
         _:{match_conditions_error, Error} ->
+            emqx_rule_metrics:inc_rules_exception(RuleId),
             ?LOG(warning, "WHERE clause exception for ~s failed: ~p",
                  [RuleID, Error]);
         _:{select_and_collect_error, Error} ->
+            emqx_rule_metrics:inc_rules_exception(RuleId),
             ?LOG(warning, "FOREACH clause exception for ~s failed: ~p",
                  [RuleID, Error]);
         _:{match_incase_error, Error} ->
+            emqx_rule_metrics:inc_rules_exception(RuleId),
             ?LOG(warning, "INCASE clause exception for ~s failed: ~p",
                  [RuleID, Error]);
         _:Error:StkTrace ->
+            emqx_rule_metrics:inc_rules_exception(RuleId),
             ?LOG(error, "Apply rule ~s failed: ~p. Stacktrace:~n~p",
                  [RuleID, Error, StkTrace])
     end,
@@ -79,6 +83,7 @@ apply_rule_discard_result(Rule, Input) ->
 
 apply_rule(Rule = #rule{id = RuleID}, Input) ->
     clear_rule_payload(),
+    ok = emqx_rule_metrics:inc_rules_matched(RuleID),
     do_apply_rule(Rule, add_metadata(Input, #{rule_id => RuleID})).
 
 do_apply_rule(#rule{id = RuleId,
@@ -89,15 +94,13 @@ do_apply_rule(#rule{id = RuleId,
                     conditions = Conditions,
                     on_action_failed = OnFailed,
                     actions = Actions}, Input) ->
-    {Selected, Collection} = ?RAISE(select_and_collect(Fields, Input),
+    {Selected, Collection} = ?RAISE(select_and_collect(Fields, Input),                                        
-                                        emqx_rule_metrics:inc_rules_exception(RuleId),
                                         {select_and_collect_error, {_EXCLASS_,_EXCPTION_,_ST_}}),
     ColumnsAndSelected = maps:merge(Input, Selected),
     case ?RAISE(match_conditions(Conditions, ColumnsAndSelected),
-                emqx_rule_metrics:inc_rules_exception(RuleId),
                 {match_conditions_error, {_EXCLASS_,_EXCPTION_,_ST_}}) of
         true ->
-            Collection2 = filter_collection(RuleId, Input, InCase, DoEach, Collection),
+            Collection2 = filter_collection(Input, InCase, DoEach, Collection),
             case Collection2 of 
                 [] -> emqx_rule_metrics:inc_rules_no_result(RuleId);
                 _ -> emqx_rule_metrics:inc_rules_passed(RuleId)
@@ -115,10 +118,8 @@ do_apply_rule(#rule{id = RuleId,
                     on_action_failed = OnFailed,
                     actions = Actions}, Input) ->
     Selected = ?RAISE(select_and_transform(Fields, Input), 
-                      emqx_rule_metrics:inc_rules_exception(RuleId),
                       {select_and_transform_error, {_EXCLASS_,_EXCPTION_,_ST_}}),
     case ?RAISE(match_conditions(Conditions, maps:merge(Input, Selected)),
-                emqx_rule_metrics:inc_rules_exception(RuleId),
                 {match_conditions_error, {_EXCLASS_,_EXCPTION_,_ST_}}) of
         true ->
             ok = emqx_rule_metrics:inc_rules_passed(RuleId),
@@ -176,18 +177,16 @@ select_and_collect([Field|More], Input, {Output, LastKV}) ->
         {nested_put(Key, Val, Output), LastKV}).
 
 %% Filter each item got from FOREACH
--dialyzer({nowarn_function, filter_collection/5}).
+-dialyzer({nowarn_function, filter_collection/4}).
-filter_collection(RuleId, Input, InCase, DoEach, {CollKey, CollVal}) ->
+filter_collection(Input, InCase, DoEach, {CollKey, CollVal}) ->
     lists:filtermap(
         fun(Item) ->
             InputAndItem = maps:merge(Input, #{CollKey => Item}),
             case ?RAISE(match_conditions(InCase, InputAndItem),
-                    emqx_rule_metrics:inc_rules_exception(RuleId),
                     {match_incase_error, {_EXCLASS_,_EXCPTION_,_ST_}}) of
                 true when DoEach == [] -> {true, InputAndItem};
                 true ->
                     {true, ?RAISE(select_and_transform(DoEach, InputAndItem),
-                                  emqx_rule_metrics:inc_rules_exception(RuleId),
                                   {doeach_error, {_EXCLASS_,_EXCPTION_,_ST_}})};
                 false -> false
             end