fix(api): respond 404 on the deletion of nonexistent rule

apps/emqx_rule_engine/src/emqx_rule_engine.app.src

@@ -2,7 +2,7 @@
 {application, emqx_rule_engine, [
     {description, "EMQX Rule Engine"},
     % strict semver, bump manually!
-    {vsn, "5.0.15"},
+    {vsn, "5.0.16"},
     {modules, []},
     {registered, [emqx_rule_engine_sup, emqx_rule_engine]},
     {applications, [kernel, stdlib, rulesql, getopt, emqx_ctl]},

apps/emqx_rule_engine/src/emqx_rule_engine_api.erl

@@ -407,6 +407,8 @@ param_path_id() ->
             {400, #{code => 'BAD_REQUEST', message => ?ERR_BADARGS(Reason)}}
     end;
 '/rules/:id'(delete, #{bindings := #{id := Id}}) ->
+    case emqx_rule_engine:get_rule(Id) of
+        {ok, _Rule} ->
             ConfPath = emqx_rule_engine:config_key_path() ++ [Id],
             case emqx_conf:remove(ConfPath, #{override_to => cluster}) of
                 {ok, _} ->
@@ -418,6 +420,9 @@ param_path_id() ->
                         reason => Reason
                     }),
                     {500, #{code => 'INTERNAL_ERROR', message => ?ERR_BADARGS(Reason)}}
+            end;
+        not_found ->
+            {404, #{code => 'NOT_FOUND', message => <<"Rule Id Not Found">>}}
     end.
 
 '/rules/:id/metrics'(get, #{bindings := #{id := Id}}) ->

apps/emqx_rule_engine/test/emqx_rule_engine_api_SUITE.erl

@@ -120,7 +120,14 @@ t_crud_rule_api(_Config) ->
         )
     ),
 
-    %ct:pal("Show After Deleted: ~p", [NotFound]),
+    ?assertMatch(
+        {404, #{code := 'NOT_FOUND'}},
+        emqx_rule_engine_api:'/rules/:id'(
+            delete,
+            #{bindings => #{id => RuleId}}
+        )
+    ),
+
     ?assertMatch(
         {404, #{code := _, message := _Message}},
         emqx_rule_engine_api:'/rules/:id'(get, #{bindings => #{id => RuleId}})

changes/ce/fix-10677.en.md

@@ -0,0 +1 @@
+In Rule API, reapond with 404 HTTP error code when trying to delete a rule that does not exist.