fix(rule): create_at lost when save to config files

apps/emqx_rule_engine/i18n/emqx_rule_engine_schema.conf

@@ -70,6 +70,17 @@ counter of the function action or the bridge channel will increase.
                           }
                   }
 
+    rules_metadata {
+                   desc {
+                         en: "Rule metadata, do not change manually"
+                         zh: "规则的元数据，不要手动修改"
+                        }
+                   label: {
+                           en: "Rule metadata"
+                           zh: "规则的元数据"
+                          }
+                  }
+
     rules_description {
                    desc {
                          en: "The description of the rule"

apps/emqx_rule_engine/src/emqx_rule_engine.erl

@@ -66,6 +66,8 @@
 %% exported for `emqx_telemetry'
 -export([get_basic_usage_info/0]).
 
+-export([now_ms/0]).
+
 %% gen_server Callbacks
 -export([
     init/1,
@@ -137,16 +139,22 @@ post_config_update(_, _Req, NewRules, OldRules, _AppEnvs) ->
 -spec load_rules() -> ok.
 load_rules() ->
     maps_foreach(
-        fun({Id, Rule}) ->
+        fun
-            {ok, _} = create_rule(Rule#{id => bin(Id)})
+            ({Id, #{metadata := #{created_at := CreatedAt}} = Rule}) ->
+                create_rule(Rule#{id => bin(Id)}, CreatedAt);
+            ({Id, Rule}) ->
+                create_rule(Rule#{id => bin(Id)})
         end,
         emqx:get_config([rule_engine, rules], #{})
     ).
 
 -spec create_rule(map()) -> {ok, rule()} | {error, term()}.
-create_rule(Params = #{id := RuleId}) when is_binary(RuleId) ->
+create_rule(Params) ->
+    create_rule(Params, now_ms()).
+
+create_rule(Params = #{id := RuleId}, CreatedAt) when is_binary(RuleId) ->
     case get_rule(RuleId) of
-        not_found -> parse_and_insert(Params, now_ms());
+        not_found -> parse_and_insert(Params, CreatedAt);
         {ok, _} -> {error, already_exists}
     end.
 

apps/emqx_rule_engine/src/emqx_rule_engine_api.erl

@@ -233,11 +233,6 @@ param_path_id() ->
 %% Rules API
 %%------------------------------------------------------------------------------
 
-%% To get around the hocon bug, we replace crlf with spaces
-replace_sql_clrf(#{<<"sql">> := SQL} = Params) ->
-    NewSQL = re:replace(SQL, "[\r\n]", " ", [{return, binary}, global]),
-    Params#{<<"sql">> => NewSQL}.
-
 '/rule_events'(get, _Params) ->
     {200, emqx_rule_events:event_info()}.
 
@@ -249,7 +244,7 @@ replace_sql_clrf(#{<<"sql">> := SQL} = Params) ->
         <<>> ->
             {400, #{code => 'BAD_REQUEST', message => <<"empty rule id is not allowed">>}};
         Id ->
-            Params = filter_out_request_body(replace_sql_clrf(Params0)),
+            Params = filter_out_request_body(add_metadata(Params0)),
             ConfPath = emqx_rule_engine:config_key_path() ++ [Id],
             case emqx_rule_engine:get_rule(Id) of
                 {ok, _Rule} ->
@@ -491,6 +486,13 @@ aggregate_metrics(AllMetrics) ->
 get_one_rule(AllRules, Id) ->
     [R || R = #{id := Id0} <- AllRules, Id0 == Id].
 
+add_metadata(Params) ->
+    Params#{
+        <<"metadata">> => #{
+            <<"created_at">> => emqx_rule_engine:now_ms()
+        }
+    }.
+
 filter_out_request_body(Conf) ->
     ExtraConfs = [
         <<"id">>,

apps/emqx_rule_engine/src/emqx_rule_engine_schema.erl

@@ -91,7 +91,8 @@ fields("rules") ->
                     example => "Some description",
                     default => <<>>
                 }
-            )}
+            )},
+        {"metadata", ?HOCON(map(), #{desc => ?DESC("rules_metadata")})}
     ];
 fields("builtin_action_republish") ->
     [