From 9a03869bd76652eaecb648941bec0dc60e27d2e2 Mon Sep 17 00:00:00 2001
From: JianBo He <heeejianbo@gmail.com>
Date: Tue, 4 Jan 2022 13:20:29 +0800
Subject: [PATCH 1/7] chore(slow-subs): change root name emqx_slow_subs >
 slow_subs

---
 apps/emqx_slow_subs/etc/emqx_slow_subs.conf   |  2 +-
 apps/emqx_slow_subs/src/emqx_slow_subs.erl    | 20 +++++++++----------
 .../emqx_slow_subs/src/emqx_slow_subs_api.erl |  6 +++---
 .../src/emqx_slow_subs_schema.erl             |  4 ++--
 .../test/emqx_slow_subs_SUITE.erl             |  2 +-
 .../test/emqx_slow_subs_api_SUITE.erl         |  4 ++--
 6 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/apps/emqx_slow_subs/etc/emqx_slow_subs.conf b/apps/emqx_slow_subs/etc/emqx_slow_subs.conf
index 9477b2e2c..8378e971c 100644
--- a/apps/emqx_slow_subs/etc/emqx_slow_subs.conf
+++ b/apps/emqx_slow_subs/etc/emqx_slow_subs.conf
@@ -2,7 +2,7 @@
 ## EMQ X Slow Subscribers Statistics
 ##--------------------------------------------------------------------
 
-emqx_slow_subs {
+slow_subs {
     enable = false
 
     threshold = 500ms
diff --git a/apps/emqx_slow_subs/src/emqx_slow_subs.erl b/apps/emqx_slow_subs/src/emqx_slow_subs.erl
index 356810d85..370f250fb 100644
--- a/apps/emqx_slow_subs/src/emqx_slow_subs.erl
+++ b/apps/emqx_slow_subs/src/emqx_slow_subs.erl
@@ -124,7 +124,7 @@ clear_history() ->
     gen_server:call(?MODULE, ?FUNCTION_NAME, ?DEF_CALL_TIMEOUT).
 
 update_settings(Conf) ->
-    emqx_conf:update([emqx_slow_subs], Conf, #{override_to => cluster}).
+    emqx_conf:update([slow_subs], Conf, #{override_to => cluster}).
 
 init_topk_tab() ->
     case ets:whereis(?TOPK_TAB) of
@@ -146,7 +146,7 @@ post_config_update(_KeyPath, _UpdateReq, NewConf, _OldConf, _AppEnvs) ->
 %%--------------------------------------------------------------------
 
 init([]) ->
-    emqx_conf:add_handler([emqx_slow_subs], ?MODULE),
+    emqx_conf:add_handler([slow_subs], ?MODULE),
 
     InitState = #{enable => false,
                   last_tick_at => 0,
@@ -154,11 +154,11 @@ init([]) ->
                   notice_timer => undefined
                  },
 
-    Enable = emqx:get_config([emqx_slow_subs, enable]),
+    Enable = emqx:get_config([slow_subs, enable]),
     {ok, check_enable(Enable, InitState)}.
 
 handle_call({update_settings, #{enable := Enable} = Conf}, _From, State) ->
-    emqx_config:put([emqx_slow_subs], Conf),
+    emqx_config:put([slow_subs], Conf),
     State2 = check_enable(Enable, State),
     {reply, ok, State2};
 
@@ -204,7 +204,7 @@ expire_tick() ->
     erlang:send_after(?EXPIRE_CHECK_INTERVAL, self(), ?FUNCTION_NAME).
 
 notice_tick() ->
-    case emqx:get_config([emqx_slow_subs, notice_interval]) of
+    case emqx:get_config([slow_subs, notice_interval]) of
         0 -> undefined;
         Interval ->
             erlang:send_after(Interval, self(), ?FUNCTION_NAME)
@@ -225,7 +225,7 @@ do_publish([], _, _) ->
     ok;
 
 do_publish(Logs, Rank, TickTime) ->
-    BatchSize = emqx:get_config([emqx_slow_subs, notice_batch_size]),
+    BatchSize = emqx:get_config([slow_subs, notice_batch_size]),
     do_publish(Logs, BatchSize, Rank, TickTime, []).
 
 do_publish([Log | T], Size, Rank, TickTime, Cache) when Size > 0 ->
@@ -254,7 +254,7 @@ publish(TickTime, Notices) ->
                   logs => lists:reverse(Notices)},
     Payload = emqx_json:encode(WindowLog),
     Msg = #message{ id = emqx_guid:gen()
-                  , qos = emqx:get_config([emqx_slow_subs, notice_qos])
+                  , qos = emqx:get_config([slow_subs, notice_qos])
                   , from = ?MODULE
                   , topic = emqx_topic:systop(?NOTICE_TOPIC_NAME)
                   , payload = Payload
@@ -264,7 +264,7 @@ publish(TickTime, Notices) ->
     ok.
 
 load(State) ->
-    MaxSizeT = emqx:get_config([emqx_slow_subs, top_k_num]),
+    MaxSizeT = emqx:get_config([slow_subs, top_k_num]),
     MaxSize = erlang:min(MaxSizeT, ?MAX_TAB_SIZE),
     _ = emqx:hook('message.slow_subs_stats',
                   {?MODULE, on_stats_update, [#{max_size => MaxSize}]}
@@ -283,7 +283,7 @@ unload(#{notice_timer := NoticeTimer, expire_timer := ExpireTimer} = State) ->
 
 do_clear(Logs) ->
     Now = ?NOW,
-    Interval = emqx:get_config([emqx_slow_subs, expire_interval]),
+    Interval = emqx:get_config([slow_subs, expire_interval]),
     Each = fun(#top_k{index = Index, last_update_time = Ts}) ->
                    case Now - Ts >= Interval of
                        true ->
@@ -330,7 +330,7 @@ check_enable(Enable, #{enable := IsEnable} = State) ->
     end.
 
 update_threshold() ->
-    Threshold = emqx:get_config([emqx_slow_subs, threshold]),
+    Threshold = emqx:get_config([slow_subs, threshold]),
     emqx_message_latency_stats:update_threshold(Threshold),
     ok.
 
diff --git a/apps/emqx_slow_subs/src/emqx_slow_subs_api.erl b/apps/emqx_slow_subs/src/emqx_slow_subs_api.erl
index 97abcfe9a..5ad7e207b 100644
--- a/apps/emqx_slow_subs/src/emqx_slow_subs_api.erl
+++ b/apps/emqx_slow_subs/src/emqx_slow_subs_api.erl
@@ -80,7 +80,7 @@ fields(record) ->
     ].
 
 conf_schema() ->
-    Ref = hoconsc:ref(emqx_slow_subs_schema, "emqx_slow_subs"),
+    Ref = hoconsc:ref(emqx_slow_subs_schema, "slow_subs"),
     hoconsc:mk(Ref, #{}).
 
 slow_subs(delete, _) ->
@@ -104,8 +104,8 @@ encode_record(#top_k{index = ?INDEX(Latency, ClientId),
       last_update_time => Ts}.
 
 settings(get, _) ->
-    {200, emqx:get_raw_config([?APP_NAME], #{})};
+    {200, emqx:get_raw_config([slow_subs], #{})};
 
 settings(put, #{body := Body}) ->
     _ = emqx_slow_subs:update_settings(Body),
-    {200, emqx:get_raw_config([?APP_NAME], #{})}.
+    {200, emqx:get_raw_config([slow_subs], #{})}.
diff --git a/apps/emqx_slow_subs/src/emqx_slow_subs_schema.erl b/apps/emqx_slow_subs/src/emqx_slow_subs_schema.erl
index 2cef9affc..4a802eb4c 100644
--- a/apps/emqx_slow_subs/src/emqx_slow_subs_schema.erl
+++ b/apps/emqx_slow_subs/src/emqx_slow_subs_schema.erl
@@ -4,9 +4,9 @@
 
 -export([roots/0, fields/1]).
 
-roots() -> ["emqx_slow_subs"].
+roots() -> ["slow_subs"].
 
-fields("emqx_slow_subs") ->
+fields("slow_subs") ->
     [ {enable, sc(boolean(), false, "switch of this function")}
     , {threshold,
        sc(emqx_schema:duration_ms(),
diff --git a/apps/emqx_slow_subs/test/emqx_slow_subs_SUITE.erl b/apps/emqx_slow_subs/test/emqx_slow_subs_SUITE.erl
index 7ecb34b6c..8111fba31 100644
--- a/apps/emqx_slow_subs/test/emqx_slow_subs_SUITE.erl
+++ b/apps/emqx_slow_subs/test/emqx_slow_subs_SUITE.erl
@@ -27,7 +27,7 @@
 -define(NOW, erlang:system_time(millisecond)).
 
 -define(BASE_CONF, <<"""
-emqx_slow_subs {
+slow_subs {
     enable = true
 	top_k_num = 5,
     expire_interval = 3000
diff --git a/apps/emqx_slow_subs/test/emqx_slow_subs_api_SUITE.erl b/apps/emqx_slow_subs/test/emqx_slow_subs_api_SUITE.erl
index a3fdd7fdb..832735054 100644
--- a/apps/emqx_slow_subs/test/emqx_slow_subs_api_SUITE.erl
+++ b/apps/emqx_slow_subs/test/emqx_slow_subs_api_SUITE.erl
@@ -35,7 +35,7 @@
 -define(CLUSTER_RPC_SHARD, emqx_cluster_rpc_shard).
 
 -define(CONF_DEFAULT, <<"""
-emqx_slow_subs
+slow_subs
 {
  enable = true
  top_k_num = 5,
@@ -121,7 +121,7 @@ t_clear(_) ->
     ?assertEqual(0, ets:info(?TOPK_TAB, size)).
 
 t_settting(_) ->
-    Conf = emqx:get_config([emqx_slow_subs]),
+    Conf = emqx:get_config([slow_subs]),
     Conf2 = Conf#{threshold => 1000},
     {ok, Data} = request_api(put,
                              api_path(["slow_subscriptions", "settings"]),

From 6bb919b65c26c00d1ca94f667bd905869b27e172 Mon Sep 17 00:00:00 2001
From: JianBo He <heeejianbo@gmail.com>
Date: Tue, 4 Jan 2022 14:11:08 +0800
Subject: [PATCH 2/7] chore(retainer): change root name emqx_retainer >
 retainer

---
 apps/emqx_retainer/etc/emqx_retainer.conf     |  2 +-
 apps/emqx_retainer/src/emqx_retainer.erl      | 22 +++++++++----------
 apps/emqx_retainer/src/emqx_retainer_api.erl  |  8 +++----
 .../src/emqx_retainer_mnesia.erl              |  4 ++--
 .../src/emqx_retainer_schema.erl              |  4 ++--
 .../test/emqx_retainer_SUITE.erl              |  2 +-
 .../test/emqx_retainer_mqtt_v5_SUITE.erl      |  2 +-
 7 files changed, 22 insertions(+), 22 deletions(-)

diff --git a/apps/emqx_retainer/etc/emqx_retainer.conf b/apps/emqx_retainer/etc/emqx_retainer.conf
index 5824186d0..f7ba44be3 100644
--- a/apps/emqx_retainer/etc/emqx_retainer.conf
+++ b/apps/emqx_retainer/etc/emqx_retainer.conf
@@ -5,7 +5,7 @@
 ## Where to store the retained messages.
 ##
 ## Notice that all nodes in the same cluster have to be configured to
-emqx_retainer {
+retainer {
   ## enable/disable emqx_retainer
   enable = true
 
diff --git a/apps/emqx_retainer/src/emqx_retainer.erl b/apps/emqx_retainer/src/emqx_retainer.erl
index adb8f7c71..ed81ece82 100644
--- a/apps/emqx_retainer/src/emqx_retainer.erl
+++ b/apps/emqx_retainer/src/emqx_retainer.erl
@@ -139,7 +139,7 @@ deliver(Result, #{context_id := Id} = Context, Pid, Topic, Cursor) ->
         false ->
             ok;
         _ ->
-            #{msg_deliver_quota := MaxDeliverNum} = emqx:get_config([?APP, flow_control]),
+            #{msg_deliver_quota := MaxDeliverNum} = emqx:get_config([retainer, flow_control]),
             case MaxDeliverNum of
                 0 ->
                     _ = [Pid ! {deliver, Topic, Msg} || Msg <- Result],
@@ -160,18 +160,18 @@ get_expiry_time(#message{headers = #{properties := #{'Message-Expiry-Interval' :
                          timestamp = Ts}) ->
     Ts + Interval * 1000;
 get_expiry_time(#message{timestamp = Ts}) ->
-    Interval = emqx_conf:get([?APP, msg_expiry_interval], ?DEF_EXPIRY_INTERVAL),
+    Interval = emqx_conf:get([retainer, msg_expiry_interval], ?DEF_EXPIRY_INTERVAL),
     case Interval of
         0 -> 0;
         _ -> Ts + Interval
     end.
 
 get_stop_publish_clear_msg() ->
-    emqx_conf:get([?APP, stop_publish_clear_msg], false).
+    emqx_conf:get([retainer, stop_publish_clear_msg], false).
 
 -spec update_config(hocon:config()) -> {ok, _} | {error, _}.
 update_config(Conf) ->
-    emqx_conf:update([emqx_retainer], Conf, #{override_to => cluster}).
+    emqx_conf:update([retainer], Conf, #{override_to => cluster}).
 
 clean() ->
     call(?FUNCTION_NAME).
@@ -196,10 +196,10 @@ stats_fun() ->
 %%--------------------------------------------------------------------
 
 init([]) ->
-    emqx_conf:add_handler([emqx_retainer], ?MODULE),
+    emqx_conf:add_handler([retainer], ?MODULE),
     init_shared_context(),
     State = new_state(),
-    #{enable := Enable} = Cfg = emqx:get_config([?APP]),
+    #{enable := Enable} = Cfg = emqx:get_config([retainer]),
     {ok,
      case Enable of
          true ->
@@ -245,7 +245,7 @@ handle_cast(Msg, State) ->
 handle_info(clear_expired, #{context := Context} = State) ->
     Mod = get_backend_module(),
     Mod:clear_expired(Context),
-    Interval = emqx_conf:get([?APP, msg_clear_interval], ?DEF_EXPIRY_INTERVAL),
+    Interval = emqx_conf:get([retainer, msg_clear_interval], ?DEF_EXPIRY_INTERVAL),
     {noreply, State#{clear_timer := add_timer(Interval, clear_expired)}, hibernate};
 
 handle_info(release_deliver_quota, #{context := Context, wait_quotas := Waits} = State) ->
@@ -261,7 +261,7 @@ handle_info(release_deliver_quota, #{context := Context, wait_quotas := Waits} =
                           end,
                           Waits2)
     end,
-    Interval = emqx:get_config([?APP, flow_control, quota_release_interval]),
+    Interval = emqx:get_config([retainer, flow_control, quota_release_interval]),
     {noreply, State#{release_quota_timer := add_timer(Interval, release_deliver_quota),
                      wait_quotas := []}};
 
@@ -294,7 +294,7 @@ new_context(Id) ->
     #{context_id => Id}.
 
 is_too_big(Size) ->
-    Limit = emqx_conf:get([?APP, max_payload_size], ?DEF_MAX_PAYLOAD_SIZE),
+    Limit = emqx_conf:get([retainer, max_payload_size], ?DEF_MAX_PAYLOAD_SIZE),
     Limit > 0 andalso (Size > Limit).
 
 %% @private
@@ -368,7 +368,7 @@ insert_shared_context(Key, Term) ->
 
 -spec get_msg_deliver_quota() -> non_neg_integer().
 get_msg_deliver_quota() ->
-    emqx:get_config([?APP, flow_control, msg_deliver_quota]).
+    emqx:get_config([retainer, flow_control, msg_deliver_quota]).
 
 -spec update_config(state(), hocons:config(), hocons:config()) -> state().
 update_config(State, Conf, OldConf) ->
@@ -461,7 +461,7 @@ check_timer(Timer, _, _) ->
 
 -spec get_backend_module() -> backend().
 get_backend_module() ->
-    #{type := Backend} = emqx:get_config([?APP, config]),
+    #{type := Backend} = emqx:get_config([retainer, config]),
     ModName = if Backend =:= built_in_database ->
                       mnesia;
                  true ->
diff --git a/apps/emqx_retainer/src/emqx_retainer_api.erl b/apps/emqx_retainer/src/emqx_retainer_api.erl
index 37aded29c..afbc69f5c 100644
--- a/apps/emqx_retainer/src/emqx_retainer_api.erl
+++ b/apps/emqx_retainer/src/emqx_retainer_api.erl
@@ -41,7 +41,7 @@ api_spec() ->
     {[lookup_retained_api(), with_topic_api(), config_api()], []}.
 
 conf_schema() ->
-    gen_schema(emqx:get_raw_config([emqx_retainer])).
+    gen_schema(emqx:get_raw_config([retainer])).
 
 message_props() ->
     properties([
@@ -126,12 +126,12 @@ with_topic_warp(Type, Params) ->
     check_backend(Type, Params, fun with_topic/2).
 
 config(get, _) ->
-    {200, emqx:get_raw_config([emqx_retainer])};
+    {200, emqx:get_raw_config([retainer])};
 
 config(put, #{body := Body}) ->
     try
         {ok, _} = emqx_retainer:update_config(Body),
-        {200,  emqx:get_raw_config([emqx_retainer])}
+        {200,  emqx:get_raw_config([retainer])}
     catch _:Reason:_ ->
             {400,
              #{code => 'UPDATE_FAILED',
@@ -188,7 +188,7 @@ to_bin_string(Data)  ->
     list_to_binary(io_lib:format("~p", [Data])).
 
 check_backend(Type, Params, Cont) ->
-    case emqx:get_config([emqx_retainer, config, type]) of
+    case emqx:get_config([retainer, config, type]) of
         built_in_database ->
             Cont(Type, Params);
         _ ->
diff --git a/apps/emqx_retainer/src/emqx_retainer_mnesia.erl b/apps/emqx_retainer/src/emqx_retainer_mnesia.erl
index 2209c760f..6bb0ae340 100644
--- a/apps/emqx_retainer/src/emqx_retainer_mnesia.erl
+++ b/apps/emqx_retainer/src/emqx_retainer_mnesia.erl
@@ -140,7 +140,7 @@ page_read(_, Topic, Page, Limit) ->
     {ok, Rows}.
 
 match_messages(_, Topic, Cursor) ->
-    MaxReadNum = emqx:get_config([?APP, flow_control, max_read_number]),
+    MaxReadNum = emqx:get_config([retainer, flow_control, max_read_number]),
     case Cursor of
         undefined ->
             case MaxReadNum of
@@ -249,7 +249,7 @@ make_cursor(Topic) ->
 
 -spec is_table_full() -> boolean().
 is_table_full() ->
-    #{max_retained_messages := Limit} = emqx:get_config([?APP, config]),
+    #{max_retained_messages := Limit} = emqx:get_config([retainer, config]),
     Limit > 0 andalso (table_size() >= Limit).
 
 -spec table_size() -> non_neg_integer().
diff --git a/apps/emqx_retainer/src/emqx_retainer_schema.erl b/apps/emqx_retainer/src/emqx_retainer_schema.erl
index d6bc598a7..308fc528f 100644
--- a/apps/emqx_retainer/src/emqx_retainer_schema.erl
+++ b/apps/emqx_retainer/src/emqx_retainer_schema.erl
@@ -6,9 +6,9 @@
 
 -define(TYPE(Type), hoconsc:mk(Type)).
 
-roots() -> ["emqx_retainer"].
+roots() -> ["retainer"].
 
-fields("emqx_retainer") ->
+fields("retainer") ->
     [ {enable, sc(boolean(), false)}
     , {msg_expiry_interval, sc(emqx_schema:duration_ms(), "0s")}
     , {msg_clear_interval, sc(emqx_schema:duration_ms(), "0s")}
diff --git a/apps/emqx_retainer/test/emqx_retainer_SUITE.erl b/apps/emqx_retainer/test/emqx_retainer_SUITE.erl
index 54657cf3d..e51417e6e 100644
--- a/apps/emqx_retainer/test/emqx_retainer_SUITE.erl
+++ b/apps/emqx_retainer/test/emqx_retainer_SUITE.erl
@@ -28,7 +28,7 @@
 all() -> emqx_common_test_helpers:all(?MODULE).
 
 -define(BASE_CONF, <<"""
-emqx_retainer {
+retainer {
     enable = true
     msg_clear_interval = 0s
     msg_expiry_interval = 0s
diff --git a/apps/emqx_retainer/test/emqx_retainer_mqtt_v5_SUITE.erl b/apps/emqx_retainer/test/emqx_retainer_mqtt_v5_SUITE.erl
index 40cd30e69..9a887d2d3 100644
--- a/apps/emqx_retainer/test/emqx_retainer_mqtt_v5_SUITE.erl
+++ b/apps/emqx_retainer/test/emqx_retainer_mqtt_v5_SUITE.erl
@@ -22,7 +22,7 @@
 -include_lib("eunit/include/eunit.hrl").
 
 -define(BASE_CONF, <<"""
-emqx_retainer {
+retainer {
     enable = true
     msg_clear_interval = 0s
     msg_expiry_interval = 0s

From af2868e59869f320444968dc9b737733ff336247 Mon Sep 17 00:00:00 2001
From: JianBo He <heeejianbo@gmail.com>
Date: Tue, 4 Jan 2022 14:23:52 +0800
Subject: [PATCH 3/7] chore(dashboard): change root name emqx_dashboard >
 dashboard

---
 apps/emqx_authn/test/emqx_authn_api_SUITE.erl         | 2 +-
 apps/emqx_dashboard/etc/emqx_dashboard.conf           | 2 +-
 apps/emqx_dashboard/src/emqx_dashboard.erl            | 2 +-
 apps/emqx_dashboard/src/emqx_dashboard_admin.erl      | 2 +-
 apps/emqx_dashboard/src/emqx_dashboard_collection.erl | 4 ++--
 apps/emqx_dashboard/src/emqx_dashboard_middleware.erl | 2 +-
 apps/emqx_dashboard/src/emqx_dashboard_schema.erl     | 4 ++--
 apps/emqx_dashboard/src/emqx_dashboard_token.erl      | 2 +-
 apps/emqx_dashboard/test/emqx_dashboard_SUITE.erl     | 2 +-
 9 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/apps/emqx_authn/test/emqx_authn_api_SUITE.erl b/apps/emqx_authn/test/emqx_authn_api_SUITE.erl
index 8a61af36a..63c631b4b 100644
--- a/apps/emqx_authn/test/emqx_authn_api_SUITE.erl
+++ b/apps/emqx_authn/test/emqx_authn_api_SUITE.erl
@@ -79,7 +79,7 @@ set_special_configs(emqx_dashboard) ->
             port => 18083
         }]
     },
-    emqx_config:put([emqx_dashboard], Config),
+    emqx_config:put([dashboard], Config),
     ok;
 set_special_configs(_App) ->
     ok.
diff --git a/apps/emqx_dashboard/etc/emqx_dashboard.conf b/apps/emqx_dashboard/etc/emqx_dashboard.conf
index ba2a68eeb..22c090457 100644
--- a/apps/emqx_dashboard/etc/emqx_dashboard.conf
+++ b/apps/emqx_dashboard/etc/emqx_dashboard.conf
@@ -2,7 +2,7 @@
 ## EMQ X Dashboard
 ##--------------------------------------------------------------------
 
-emqx_dashboard {
+dashboard {
     default_username = "admin"
     default_password = "public"
     ## notice: sample_interval should be divisible by 60.
diff --git a/apps/emqx_dashboard/src/emqx_dashboard.erl b/apps/emqx_dashboard/src/emqx_dashboard.erl
index fbd6d32eb..a8ec70b1b 100644
--- a/apps/emqx_dashboard/src/emqx_dashboard.erl
+++ b/apps/emqx_dashboard/src/emqx_dashboard.erl
@@ -90,7 +90,7 @@ listeners() ->
         Name = listener_name(Protocol, Port),
         RanchOptions = ranch_opts(maps:without([protocol], ListenerOptions)),
         {Name, Protocol, Port, RanchOptions}
-    end || ListenerOptions <- emqx_conf:get([emqx_dashboard, listeners], [])].
+    end || ListenerOptions <- emqx_conf:get([dashboard, listeners], [])].
 
 ranch_opts(RanchOptions) ->
     Keys = [ {ack_timeout, handshake_timeout}
diff --git a/apps/emqx_dashboard/src/emqx_dashboard_admin.erl b/apps/emqx_dashboard/src/emqx_dashboard_admin.erl
index 39e73f659..158c42e6e 100644
--- a/apps/emqx_dashboard/src/emqx_dashboard_admin.erl
+++ b/apps/emqx_dashboard/src/emqx_dashboard_admin.erl
@@ -229,7 +229,7 @@ add_default_user() ->
     add_default_user(binenv(default_username), binenv(default_password)).
 
 binenv(Key) ->
-    iolist_to_binary(emqx_conf:get([emqx_dashboard, Key], "")).
+    iolist_to_binary(emqx_conf:get([dashboard, Key], "")).
 
 add_default_user(Username, Password) when ?EMPTY_KEY(Username) orelse ?EMPTY_KEY(Password) ->
     {ok, empty};
diff --git a/apps/emqx_dashboard/src/emqx_dashboard_collection.erl b/apps/emqx_dashboard/src/emqx_dashboard_collection.erl
index b125dfa3e..00f9d6d10 100644
--- a/apps/emqx_dashboard/src/emqx_dashboard_collection.erl
+++ b/apps/emqx_dashboard/src/emqx_dashboard_collection.erl
@@ -55,7 +55,7 @@ get_collect() -> gen_server:call(whereis(?MODULE), get_collect).
 init([]) ->
     timer(next_interval(), collect),
     timer(get_today_remaining_seconds(), clear_expire_data),
-    ExpireInterval = emqx_conf:get([emqx_dashboard, monitor, interval], ?EXPIRE_INTERVAL),
+    ExpireInterval = emqx_conf:get([dashboard, monitor, interval], ?EXPIRE_INTERVAL),
     State = #{
         count => count(),
         expire_interval => ExpireInterval,
@@ -75,7 +75,7 @@ next_interval() ->
     (1000 * interval()) - (erlang:system_time(millisecond) rem (1000 * interval())) - 1.
 
 interval() ->
-    emqx_conf:get([?APP, sample_interval], ?DEFAULT_INTERVAL).
+    emqx_conf:get([dashboard, sample_interval], ?DEFAULT_INTERVAL).
 
 count() ->
     60 div interval().
diff --git a/apps/emqx_dashboard/src/emqx_dashboard_middleware.erl b/apps/emqx_dashboard/src/emqx_dashboard_middleware.erl
index 7c22ee3ef..77b6dbdd0 100644
--- a/apps/emqx_dashboard/src/emqx_dashboard_middleware.erl
+++ b/apps/emqx_dashboard/src/emqx_dashboard_middleware.erl
@@ -21,7 +21,7 @@
 -export([execute/2]).
 
 execute(Req, Env) ->
-    CORS = emqx_conf:get([emqx_dashboard, cors], false),
+    CORS = emqx_conf:get([dashboard, cors], false),
     case CORS andalso cowboy_req:header(<<"origin">>, Req, undefined) of
         false ->
             {ok, Req, Env};
diff --git a/apps/emqx_dashboard/src/emqx_dashboard_schema.erl b/apps/emqx_dashboard/src/emqx_dashboard_schema.erl
index cd1bcf0d8..fddf8ca62 100644
--- a/apps/emqx_dashboard/src/emqx_dashboard_schema.erl
+++ b/apps/emqx_dashboard/src/emqx_dashboard_schema.erl
@@ -22,9 +22,9 @@
         ,namespace/0]).
 
 namespace() -> <<"dashboard">>.
-roots() -> ["emqx_dashboard"].
+roots() -> ["dashboard"].
 
-fields("emqx_dashboard") ->
+fields("dashboard") ->
     [ {listeners, hoconsc:array(hoconsc:union([hoconsc:ref(?MODULE, "http"),
                                                hoconsc:ref(?MODULE, "https")]))}
     , {default_username, fun default_username/1}
diff --git a/apps/emqx_dashboard/src/emqx_dashboard_token.erl b/apps/emqx_dashboard/src/emqx_dashboard_token.erl
index e8c9f8619..515a59cae 100644
--- a/apps/emqx_dashboard/src/emqx_dashboard_token.erl
+++ b/apps/emqx_dashboard/src/emqx_dashboard_token.erl
@@ -163,7 +163,7 @@ jwt_expiration_time() ->
     erlang:system_time(millisecond) + token_ttl().
 
 token_ttl() ->
-    emqx_conf:get([emqx_dashboard, token_expired_time], ?EXPTIME).
+    emqx_conf:get([dashboard, token_expired_time], ?EXPTIME).
 
 format(Token, Username, ExpTime) ->
     #?ADMIN_JWT{
diff --git a/apps/emqx_dashboard/test/emqx_dashboard_SUITE.erl b/apps/emqx_dashboard/test/emqx_dashboard_SUITE.erl
index 11d8e8052..9fa20a6d8 100644
--- a/apps/emqx_dashboard/test/emqx_dashboard_SUITE.erl
+++ b/apps/emqx_dashboard/test/emqx_dashboard_SUITE.erl
@@ -94,7 +94,7 @@ set_special_configs(emqx_dashboard) ->
                default_username => <<"admin">>,
                default_password => <<"public">>
               },
-    emqx_config:put([emqx_dashboard], Config),
+    emqx_config:put([dashboard], Config),
     ok;
 set_special_configs(_) ->
     ok.

From 10b110447cea66165125969c461c2ceb656e86f5 Mon Sep 17 00:00:00 2001
From: JianBo He <heeejianbo@gmail.com>
Date: Tue, 4 Jan 2022 15:30:24 +0800
Subject: [PATCH 4/7] chore(exhook): change root name emqx_exhook > exhook

---
 apps/emqx_exhook/etc/emqx_exhook.conf             |  2 +-
 apps/emqx_exhook/src/emqx_exhook_api.erl          |  8 ++++----
 apps/emqx_exhook/src/emqx_exhook_mgr.erl          |  8 ++++----
 apps/emqx_exhook/src/emqx_exhook_schema.erl       |  6 +++---
 apps/emqx_exhook/test/emqx_exhook_SUITE.erl       | 10 +++++-----
 apps/emqx_exhook/test/emqx_exhook_api_SUITE.erl   | 15 ++++++++-------
 apps/emqx_exhook/test/props/prop_exhook_hooks.erl | 11 ++++++-----
 .../test/emqx_mgmt_api_test_util.erl              |  2 +-
 8 files changed, 32 insertions(+), 30 deletions(-)

diff --git a/apps/emqx_exhook/etc/emqx_exhook.conf b/apps/emqx_exhook/etc/emqx_exhook.conf
index 8769e9a2d..fcdb0de96 100644
--- a/apps/emqx_exhook/etc/emqx_exhook.conf
+++ b/apps/emqx_exhook/etc/emqx_exhook.conf
@@ -2,7 +2,7 @@
 ## EMQ X Hooks
 ##====================================================================
 
-emqx_exhook {
+exhook {
 
     servers = [
     ##{
diff --git a/apps/emqx_exhook/src/emqx_exhook_api.erl b/apps/emqx_exhook/src/emqx_exhook_api.erl
index 7de57f724..bd3351616 100644
--- a/apps/emqx_exhook/src/emqx_exhook_api.erl
+++ b/apps/emqx_exhook/src/emqx_exhook_api.erl
@@ -146,7 +146,7 @@ exhooks(get, _) ->
     {200, ServerL2};
 
 exhooks(post, #{body := Body}) ->
-    case emqx_exhook_mgr:update_config([emqx_exhook, servers], {add, Body}) of
+    case emqx_exhook_mgr:update_config([exhook, servers], {add, Body}) of
         {ok, Result} ->
             {201, Result};
         {error, Error} ->
@@ -168,7 +168,7 @@ action_with_name(get, #{bindings := #{name := Name}}) ->
     end;
 
 action_with_name(put, #{bindings := #{name := Name}, body := Body}) ->
-    case emqx_exhook_mgr:update_config([emqx_exhook, servers],
+    case emqx_exhook_mgr:update_config([exhook, servers],
                                        {update, Name, Body}) of
         {ok, not_found} ->
             {400, #{code => <<"BAD_REQUEST">>,
@@ -187,7 +187,7 @@ action_with_name(put, #{bindings := #{name := Name}, body := Body}) ->
     end;
 
 action_with_name(delete, #{bindings := #{name := Name}}) ->
-    case emqx_exhook_mgr:update_config([emqx_exhook, servers],
+    case emqx_exhook_mgr:update_config([exhook, servers],
                                        {delete, Name}) of
         {ok, _} ->
             {200};
@@ -200,7 +200,7 @@ action_with_name(delete, #{bindings := #{name := Name}}) ->
 move(post, #{bindings := #{name := Name}, body := Body}) ->
     #{<<"position">> := PositionT, <<"related">> := Related} = Body,
     Position = erlang:binary_to_atom(PositionT),
-    case emqx_exhook_mgr:update_config([emqx_exhook, servers],
+    case emqx_exhook_mgr:update_config([exhook, servers],
                                        {move, Name, Position, Related}) of
         {ok, ok} ->
             {200};
diff --git a/apps/emqx_exhook/src/emqx_exhook_mgr.erl b/apps/emqx_exhook/src/emqx_exhook_mgr.erl
index 35bbe00a4..d3d429021 100644
--- a/apps/emqx_exhook/src/emqx_exhook_mgr.erl
+++ b/apps/emqx_exhook/src/emqx_exhook_mgr.erl
@@ -108,10 +108,10 @@ lookup(Name) ->
     call({lookup, Name}).
 
 enable(Name) ->
-    update_config([emqx_exhook, servers], {enable, Name, true}).
+    update_config([exhook, servers], {enable, Name, true}).
 
 disable(Name) ->
-    update_config([emqx_exhook, servers], {enable, Name, false}).
+    update_config([exhook, servers], {enable, Name, false}).
 
 server_status(Name) ->
     call({server_status, Name}).
@@ -176,8 +176,8 @@ post_config_update(_KeyPath, UpdateReq, NewConf, _OldConf, _AppEnvs) ->
 
 init([]) ->
     process_flag(trap_exit, true),
-    emqx_conf:add_handler([emqx_exhook, servers], ?MODULE),
-    ServerL = emqx:get_config([emqx_exhook, servers]),
+    emqx_conf:add_handler([exhook, servers], ?MODULE),
+    ServerL = emqx:get_config([exhook, servers]),
     {Waiting, Running, Stopped} = load_all_servers(ServerL),
     Orders = reorder(ServerL),
     {ok, ensure_reload_timer(
diff --git a/apps/emqx_exhook/src/emqx_exhook_schema.erl b/apps/emqx_exhook/src/emqx_exhook_schema.erl
index 88a61ef1c..a8666798c 100644
--- a/apps/emqx_exhook/src/emqx_exhook_schema.erl
+++ b/apps/emqx_exhook/src/emqx_exhook_schema.erl
@@ -34,11 +34,11 @@
 
 -export([namespace/0, roots/0, fields/1, server_config/0]).
 
-namespace() -> emqx_exhook.
+namespace() -> exhook.
 
-roots() -> [emqx_exhook].
+roots() -> [exhook].
 
-fields(emqx_exhook) ->
+fields(exhook) ->
     [{servers,
       sc(hoconsc:array(ref(server)),
           #{default => []})}
diff --git a/apps/emqx_exhook/test/emqx_exhook_SUITE.erl b/apps/emqx_exhook/test/emqx_exhook_SUITE.erl
index 490e002e3..002900f1e 100644
--- a/apps/emqx_exhook/test/emqx_exhook_SUITE.erl
+++ b/apps/emqx_exhook/test/emqx_exhook_SUITE.erl
@@ -24,11 +24,11 @@
 -define(CLUSTER_RPC_SHARD, emqx_cluster_rpc_shard).
 
 -define(CONF_DEFAULT, <<"
-emqx_exhook
-{servers = [
-            {name = default,
-             url = \"http://127.0.0.1:9000\"
-            }]
+exhook {
+  servers = [
+    { name = default,
+      url = \"http://127.0.0.1:9000\"
+    }]
 }
 ">>).
 
diff --git a/apps/emqx_exhook/test/emqx_exhook_api_SUITE.erl b/apps/emqx_exhook/test/emqx_exhook_api_SUITE.erl
index f95f2b98c..b82451714 100644
--- a/apps/emqx_exhook/test/emqx_exhook_api_SUITE.erl
+++ b/apps/emqx_exhook/test/emqx_exhook_api_SUITE.erl
@@ -27,12 +27,13 @@
 -define(CLUSTER_RPC_SHARD, emqx_cluster_rpc_shard).
 
 -define(CONF_DEFAULT, <<"
-emqx_exhook {servers = [
-                        {name = default,
-                         url = \"http://127.0.0.1:9000\"
-                         }
-                       ]
-            }
+exhook {
+  servers =
+    [ { name = default,
+        url = \"http://127.0.0.1:9000\"
+      }
+    ]
+}
 ">>).
 
 all() ->
@@ -49,7 +50,7 @@ init_per_suite(Config) ->
     _ = emqx_exhook_demo_svr:start(),
     ok = emqx_config:init_load(emqx_exhook_schema, ?CONF_DEFAULT),
     emqx_mgmt_api_test_util:init_suite([emqx_exhook]),
-    [Conf] = emqx:get_config([emqx_exhook, servers]),
+    [Conf] = emqx:get_config([exhook, servers]),
     [{template, Conf} | Config].
 
 end_per_suite(Config) ->
diff --git a/apps/emqx_exhook/test/props/prop_exhook_hooks.erl b/apps/emqx_exhook/test/props/prop_exhook_hooks.erl
index 284e2b89b..84999e4a8 100644
--- a/apps/emqx_exhook/test/props/prop_exhook_hooks.erl
+++ b/apps/emqx_exhook/test/props/prop_exhook_hooks.erl
@@ -31,11 +31,12 @@
         ]).
 
 -define(CONF_DEFAULT, <<"
-emqx_exhook
-{servers = [
-            {name = default,
-             url = \"http://127.0.0.1:9000\"
-            }]
+exhook {
+  servers =
+    [ { name = default,
+        url = \"http://127.0.0.1:9000\"
+      }
+    ]
 }
 ">>).
 
diff --git a/apps/emqx_management/test/emqx_mgmt_api_test_util.erl b/apps/emqx_management/test/emqx_mgmt_api_test_util.erl
index 8dcbfcc5e..42481abcb 100644
--- a/apps/emqx_management/test/emqx_mgmt_api_test_util.erl
+++ b/apps/emqx_management/test/emqx_mgmt_api_test_util.erl
@@ -45,7 +45,7 @@ set_special_configs(emqx_dashboard) ->
                                port => 18083
                               }]
               },
-    emqx_config:put([emqx_dashboard], Config),
+    emqx_config:put([dashboard], Config),
     ok;
 set_special_configs(_App) ->
     ok.

From 12cc9065f879d92ce1f395d4e6dea5df6b2241df Mon Sep 17 00:00:00 2001
From: JianBo He <heeejianbo@gmail.com>
Date: Tue, 4 Jan 2022 15:34:43 +0800
Subject: [PATCH 5/7] chore(limiter): change root name emqx_limiter > limiter

---
 apps/emqx/src/emqx_limiter/etc/emqx_limiter.conf |  3 ++-
 .../src/emqx_limiter/src/emqx_limiter_schema.erl | 16 ++++++++--------
 .../src/emqx_limiter/src/emqx_limiter_server.erl |  4 ++--
 .../emqx_limiter/src/emqx_limiter_server_sup.erl |  2 +-
 apps/emqx/test/emqx_channel_SUITE.erl            |  6 +++---
 apps/emqx/test/emqx_ratelimiter_SUITE.erl        | 14 +++++++-------
 6 files changed, 23 insertions(+), 22 deletions(-)

diff --git a/apps/emqx/src/emqx_limiter/etc/emqx_limiter.conf b/apps/emqx/src/emqx_limiter/etc/emqx_limiter.conf
index 5c199e63f..78cb35207 100644
--- a/apps/emqx/src/emqx_limiter/etc/emqx_limiter.conf
+++ b/apps/emqx/src/emqx_limiter/etc/emqx_limiter.conf
@@ -1,7 +1,8 @@
 ##--------------------------------------------------------------------
 ## Emq X Rate Limiter
 ##--------------------------------------------------------------------
-emqx_limiter {
+
+limiter {
   bytes_in {
     global.rate = infinity         # token generation rate
     zone.default.rate = infinity
diff --git a/apps/emqx/src/emqx_limiter/src/emqx_limiter_schema.erl b/apps/emqx/src/emqx_limiter/src/emqx_limiter_schema.erl
index 37002edc4..ed87ce6c2 100644
--- a/apps/emqx/src/emqx_limiter/src/emqx_limiter_schema.erl
+++ b/apps/emqx/src/emqx_limiter/src/emqx_limiter_schema.erl
@@ -56,16 +56,16 @@
 
 -import(emqx_schema, [sc/2, map/2]).
 
-roots() -> [emqx_limiter].
-
-fields(emqx_limiter) ->
-    [ {bytes_in, sc(ref(limiter), #{})}
-    , {message_in, sc(ref(limiter), #{})}
-    , {connection, sc(ref(limiter), #{})}
-    , {message_routing, sc(ref(limiter), #{})}
-    ];
+roots() -> [limiter].
 
 fields(limiter) ->
+    [ {bytes_in, sc(ref(limiter_opts), #{})}
+    , {message_in, sc(ref(limiter_opts), #{})}
+    , {connection, sc(ref(limiter_opts), #{})}
+    , {message_routing, sc(ref(limiter_opts), #{})}
+    ];
+
+fields(limiter_opts) ->
     [ {global, sc(ref(rate_burst), #{})}
     , {zone, sc(map("zone name", ref(rate_burst)), #{})}
     , {bucket, sc(map("bucket id", ref(bucket)),
diff --git a/apps/emqx/src/emqx_limiter/src/emqx_limiter_server.erl b/apps/emqx/src/emqx_limiter/src/emqx_limiter_server.erl
index f683ef68e..5e189a8b1 100644
--- a/apps/emqx/src/emqx_limiter/src/emqx_limiter_server.erl
+++ b/apps/emqx/src/emqx_limiter/src/emqx_limiter_server.erl
@@ -95,7 +95,7 @@
 -spec connect(limiter_type(),
               bucket_name() | #{limiter_type() => bucket_name()}) -> emqx_htb_limiter:limiter().
 connect(Type, BucketName) when is_atom(BucketName) ->
-    Path = [emqx_limiter, Type, bucket, BucketName],
+    Path = [limiter, Type, bucket, BucketName],
     case emqx:get_config(Path, undefined) of
         undefined ->
             ?SLOG(error, #{msg => "bucket_config_not_found", path => Path}),
@@ -447,7 +447,7 @@ dispatch_burst_to_buckets([], _, Alloced, Nodes) ->
 init_tree(Type, State) ->
     #{global := Global,
       zone := Zone,
-      bucket := Bucket} = emqx:get_config([emqx_limiter, Type]),
+      bucket := Bucket} = emqx:get_config([limiter, Type]),
     {Factor, Root} = make_root(Global, Zone),
     State2 = State#{root := Root},
     {NodeId, State3} = make_zone(maps:to_list(Zone), Factor, 1, State2),
diff --git a/apps/emqx/src/emqx_limiter/src/emqx_limiter_server_sup.erl b/apps/emqx/src/emqx_limiter/src/emqx_limiter_server_sup.erl
index 7698449db..7f8d227ec 100644
--- a/apps/emqx/src/emqx_limiter/src/emqx_limiter_server_sup.erl
+++ b/apps/emqx/src/emqx_limiter/src/emqx_limiter_server_sup.erl
@@ -89,6 +89,6 @@ make_child(Type) ->
       modules => [emqx_limiter_server]}.
 
 childs() ->
-    Conf = emqx:get_config([emqx_limiter]),
+    Conf = emqx:get_config([limiter]),
     Types = maps:keys(Conf),
     [make_child(Type) || Type <- Types].
diff --git a/apps/emqx/test/emqx_channel_SUITE.erl b/apps/emqx/test/emqx_channel_SUITE.erl
index da7e24058..9e64e70c9 100644
--- a/apps/emqx/test/emqx_channel_SUITE.erl
+++ b/apps/emqx/test/emqx_channel_SUITE.erl
@@ -130,7 +130,7 @@ basic_conf() ->
       stats => stats_conf(),
       listeners => listeners_conf(),
       zones => zone_conf(),
-      emqx_limiter => emqx:get_config([emqx_limiter])
+      limiter => emqx:get_config([limiter])
     }.
 
 set_test_listener_confs() ->
@@ -201,7 +201,7 @@ modify_limiter(TestCase, NewConf) ->
 
 %% per_client 5/1s,5
 %% aggregated 10/1s,10
-modify_limiter(#{emqx_limiter := Limiter} = NewConf) ->
+modify_limiter(#{limiter := Limiter} = NewConf) ->
     #{message_routing := #{bucket := Bucket} = Routing} = Limiter,
     #{default := #{per_client := Client} = Default} = Bucket,
     Client2 = Client#{rate := 5,
@@ -216,7 +216,7 @@ modify_limiter(#{emqx_limiter := Limiter} = NewConf) ->
     Bucket2 = Bucket#{default := Default2},
     Routing2 = Routing#{bucket := Bucket2},
 
-    NewConf2 = NewConf#{emqx_limiter := Limiter#{message_routing := Routing2}},
+    NewConf2 = NewConf#{limiter := Limiter#{message_routing := Routing2}},
     emqx_config:put(NewConf2),
     emqx_limiter_manager:restart_server(message_routing),
     ok.
diff --git a/apps/emqx/test/emqx_ratelimiter_SUITE.erl b/apps/emqx/test/emqx_ratelimiter_SUITE.erl
index 6d21399ce..17a63e79a 100644
--- a/apps/emqx/test/emqx_ratelimiter_SUITE.erl
+++ b/apps/emqx/test/emqx_ratelimiter_SUITE.erl
@@ -25,7 +25,7 @@
 -include_lib("common_test/include/ct.hrl").
 
 -define(BASE_CONF, <<"""
-emqx_limiter {
+limiter {
   bytes_in {
     global.rate = infinity
     zone.default.rate = infinity
@@ -496,7 +496,7 @@ start_client(Name, EndTime, Counter, Number) ->
 
 start_client(Name, EndTime, Counter) ->
     #{per_client := PerClient} =
-        emqx_config:get([emqx_limiter, message_routing, bucket, Name]),
+        emqx_config:get([limiter, message_routing, bucket, Name]),
     #{rate := Rate} = PerClient,
     Client = #client{start = ?NOW,
                      endtime = EndTime,
@@ -578,18 +578,18 @@ to_rate(Str) ->
     Rate.
 
 with_global(Modifier, ZoneName, ZoneModifier, Buckets, Case) ->
-    Path = [emqx_limiter, message_routing],
+    Path = [limiter, message_routing],
     #{global := Global} = Cfg = emqx_config:get(Path),
     Cfg2 = Cfg#{global := Modifier(Global)},
     with_zone(Cfg2, ZoneName, ZoneModifier, Buckets, Case).
 
 with_zone(Name, Modifier, Buckets, Case) ->
-    Path = [emqx_limiter, message_routing],
+    Path = [limiter, message_routing],
     Cfg = emqx_config:get(Path),
     with_zone(Cfg, Name, Modifier, Buckets, Case).
 
 with_zone(Cfg, Name, Modifier, Buckets, Case) ->
-    Path = [emqx_limiter, message_routing],
+    Path = [limiter, message_routing],
     #{zone := ZoneCfgs,
       bucket := BucketCfgs} = Cfg,
     ZoneCfgs2 = apply_modifier(Name, Modifier, ZoneCfgs),
@@ -598,11 +598,11 @@ with_zone(Cfg, Name, Modifier, Buckets, Case) ->
     with_config(Path, fun(_) -> Cfg2 end, Case).
 
 with_bucket(Bucket, Modifier, Case) ->
-    Path = [emqx_limiter, message_routing, bucket, Bucket],
+    Path = [limiter, message_routing, bucket, Bucket],
     with_config(Path, Modifier, Case).
 
 with_per_client(Bucket, Modifier, Case) ->
-    Path = [emqx_limiter, message_routing, bucket, Bucket, per_client],
+    Path = [limiter, message_routing, bucket, Bucket, per_client],
     with_config(Path, Modifier, Case).
 
 with_config(Path, Modifier, Case) ->

From b1959086d952cb34f88d7af55406a39442fefb3c Mon Sep 17 00:00:00 2001
From: JianBo He <heeejianbo@gmail.com>
Date: Tue, 4 Jan 2022 16:57:52 +0800
Subject: [PATCH 6/7] chore: fix elvis warnings

---
 .../emqx_limiter/src/emqx_limiter_schema.erl  |  3 +-
 .../emqx_limiter/src/emqx_limiter_server.erl  |  7 +-
 apps/emqx/test/emqx_channel_SUITE.erl         | 14 ++-
 apps/emqx_exhook/src/emqx_exhook_api.erl      |  6 +-
 apps/emqx_retainer/src/emqx_retainer.erl      |  8 +-
 .../src/emqx_retainer_mnesia.erl              |  6 +-
 .../test/emqx_retainer_SUITE.erl              | 96 +++++++++++++++----
 .../test/emqx_retainer_mqtt_v5_SUITE.erl      | 63 +++++++++---
 apps/emqx_slow_subs/src/emqx_slow_subs.erl    |  3 +-
 .../emqx_slow_subs/src/emqx_slow_subs_api.erl | 15 ++-
 .../src/emqx_slow_subs_schema.erl             |  4 +-
 11 files changed, 172 insertions(+), 53 deletions(-)

diff --git a/apps/emqx/src/emqx_limiter/src/emqx_limiter_schema.erl b/apps/emqx/src/emqx_limiter/src/emqx_limiter_schema.erl
index ed87ce6c2..91936c8f0 100644
--- a/apps/emqx/src/emqx_limiter/src/emqx_limiter_schema.erl
+++ b/apps/emqx/src/emqx_limiter/src/emqx_limiter_schema.erl
@@ -94,7 +94,8 @@ fields(client_bucket) ->
     , {initial, sc(initial(), #{default => "0"})}
       %% low_water_mark add for emqx_channel and emqx_session
       %% both modules consume first and then check
-      %% so we need to use this value to prevent excessive consumption (e.g, consumption from an empty bucket)
+      %% so we need to use this value to prevent excessive consumption
+      %% (e.g, consumption from an empty bucket)
     , {low_water_mark, sc(initial(),
                           #{desc => "if the remaining tokens are lower than this value,
 the check/consume will succeed, but it will be forced to hang for a short period of time",
diff --git a/apps/emqx/src/emqx_limiter/src/emqx_limiter_server.erl b/apps/emqx/src/emqx_limiter/src/emqx_limiter_server.erl
index 5e189a8b1..1bccbf2a0 100644
--- a/apps/emqx/src/emqx_limiter/src/emqx_limiter_server.erl
+++ b/apps/emqx/src/emqx_limiter/src/emqx_limiter_server.erl
@@ -89,6 +89,8 @@
 -export_type([index/0]).
 -import(emqx_limiter_decimal, [add/2, sub/2, mul/2,  put_to_counter/3]).
 
+-elvis([{elvis_style, no_if_expression, disable}]).
+
 %%--------------------------------------------------------------------
 %% API
 %%--------------------------------------------------------------------
@@ -337,8 +339,9 @@ longitudinal(#{id := Id,
 
     case lists:min([ShouldAlloc, Flow, Capacity]) of
         Avaiable when Avaiable > 0 ->
-            %% XXX if capacity is infinity, and flow always > 0, the value in counter
-            %% will be overflow at some point in the future, do we need to deal with this situation???
+            %% XXX if capacity is infinity, and flow always > 0, the value in
+            %% counter will be overflow at some point in the future, do we need
+            %% to deal with this situation???
             {Inc, Node2} = emqx_limiter_correction:add(Avaiable, Node),
             counters:add(Counter, Index, Inc),
 
diff --git a/apps/emqx/test/emqx_channel_SUITE.erl b/apps/emqx/test/emqx_channel_SUITE.erl
index 9e64e70c9..19bc2b3c3 100644
--- a/apps/emqx/test/emqx_channel_SUITE.erl
+++ b/apps/emqx/test/emqx_channel_SUITE.erl
@@ -923,7 +923,12 @@ t_ws_cookie_init(_) ->
                  conn_mod => emqx_ws_connection,
                  ws_cookie => WsCookie
                 },
-    Channel = emqx_channel:init(ConnInfo, #{zone => default, limiter => limiter_cfg(), listener => {tcp, default}}),
+    Channel = emqx_channel:init(
+                ConnInfo,
+                #{zone => default,
+                  limiter => limiter_cfg(),
+                  listener => {tcp, default}
+                 }),
     ?assertMatch(#{ws_cookie := WsCookie}, emqx_channel:info(clientinfo, Channel)).
 
 %%--------------------------------------------------------------------
@@ -948,7 +953,12 @@ channel(InitFields) ->
     maps:fold(fun(Field, Value, Channel) ->
                       emqx_channel:set_field(Field, Value, Channel)
               end,
-              emqx_channel:init(ConnInfo, #{zone => default, limiter => limiter_cfg(), listener => {tcp, default}}),
+              emqx_channel:init(
+                ConnInfo,
+                #{zone => default,
+                  limiter => limiter_cfg(),
+                  listener => {tcp, default}
+                 }),
               maps:merge(#{clientinfo => clientinfo(),
                            session    => session(),
                            conn_state => connected
diff --git a/apps/emqx_exhook/src/emqx_exhook_api.erl b/apps/emqx_exhook/src/emqx_exhook_api.erl
index bd3351616..7581dd17b 100644
--- a/apps/emqx_exhook/src/emqx_exhook_api.erl
+++ b/apps/emqx_exhook/src/emqx_exhook_api.erl
@@ -77,7 +77,8 @@ schema("/exhooks/:name") ->
                   description => <<"Delete the server">>,
                   parameters => params_server_name_in_path(),
                   responses => #{204 => <<>>,
-                                 500 => error_codes([?BAD_RPC], <<"Bad RPC">>)                                }
+                                 500 => error_codes([?BAD_RPC], <<"Bad RPC">>)
+                                }
                  }
      };
 
@@ -176,7 +177,8 @@ action_with_name(put, #{bindings := #{name := Name}, body := Body}) ->
                    }};
         {ok, {error, Reason}} ->
             {400, #{code => <<"BAD_REQUEST">>,
-                    message => unicode:characters_to_binary(io_lib:format("Error Reason:~p~n", [Reason]))
+                    message => unicode:characters_to_binary(
+                                 io_lib:format("Error Reason:~p~n", [Reason]))
                    }};
         {ok, _} ->
             {200};
diff --git a/apps/emqx_retainer/src/emqx_retainer.erl b/apps/emqx_retainer/src/emqx_retainer.erl
index ed81ece82..3f43c1597 100644
--- a/apps/emqx_retainer/src/emqx_retainer.erl
+++ b/apps/emqx_retainer/src/emqx_retainer.erl
@@ -461,11 +461,9 @@ check_timer(Timer, _, _) ->
 
 -spec get_backend_module() -> backend().
 get_backend_module() ->
-    #{type := Backend} = emqx:get_config([retainer, config]),
-    ModName = if Backend =:= built_in_database ->
-                      mnesia;
-                 true ->
-                      Backend
+    ModName = case emqx:get_config([retainer, config]) of
+                  #{type := built_in_database} -> mnesia;
+                  #{type := Backend} -> Backend
               end,
     erlang:list_to_existing_atom(io_lib:format("~ts_~ts", [?APP, ModName])).
 
diff --git a/apps/emqx_retainer/src/emqx_retainer_mnesia.erl b/apps/emqx_retainer/src/emqx_retainer_mnesia.erl
index 6bb0ae340..28be3aa55 100644
--- a/apps/emqx_retainer/src/emqx_retainer_mnesia.erl
+++ b/apps/emqx_retainer/src/emqx_retainer_mnesia.erl
@@ -95,7 +95,11 @@ store_retained(_, Msg =#message{topic = Topic}) ->
             end,
             case mria:transaction(?RETAINER_SHARD, Fun) of
                 {atomic, ok} ->  ok;
-                {aborted, Reason} -> ?SLOG(error, #{msg => "failed_to_retain_message", topic => Topic, reason => Reason})
+                {aborted, Reason} ->
+                    ?SLOG(error, #{ msg => "failed_to_retain_message"
+                                  , topic => Topic
+                                  , reason => Reason
+                                  })
             end
     end.
 
diff --git a/apps/emqx_retainer/test/emqx_retainer_SUITE.erl b/apps/emqx_retainer/test/emqx_retainer_SUITE.erl
index e51417e6e..54e19e42c 100644
--- a/apps/emqx_retainer/test/emqx_retainer_SUITE.erl
+++ b/apps/emqx_retainer/test/emqx_retainer_SUITE.erl
@@ -90,7 +90,10 @@ t_store_and_clean(_) ->
     {ok, C1} = emqtt:start_link([{clean_start, true}, {proto_ver, v5}]),
     {ok, _} = emqtt:connect(C1),
 
-    emqtt:publish(C1, <<"retained">>, <<"this is a retained message">>, [{qos, 0}, {retain, true}]),
+    emqtt:publish(
+      C1, <<"retained">>,
+      <<"this is a retained message">>,
+      [{qos, 0}, {retain, true}]),
     timer:sleep(100),
     {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained">>, [{qos, 0}, {rh, 0}]),
     ?assertEqual(1, length(receive_messages(1))),
@@ -118,7 +121,10 @@ t_retain_handling(_) ->
     ?assertEqual(0, length(receive_messages(1))),
     {ok, #{}, [0]} = emqtt:unsubscribe(C1, <<"retained/#">>),
 
-    emqtt:publish(C1, <<"retained">>, <<"this is a retained message">>, [{qos, 0}, {retain, true}]),
+    emqtt:publish(
+      C1, <<"retained">>,
+      <<"this is a retained message">>,
+      [{qos, 0}, {retain, true}]),
 
     {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained">>, [{qos, 0}, {rh, 0}]),
     ?assertEqual(1, length(receive_messages(1))),
@@ -148,9 +154,18 @@ t_retain_handling(_) ->
 t_wildcard_subscription(_) ->
     {ok, C1} = emqtt:start_link([{clean_start, true}, {proto_ver, v5}]),
     {ok, _} = emqtt:connect(C1),
-    emqtt:publish(C1, <<"retained/0">>, <<"this is a retained message 0">>, [{qos, 0}, {retain, true}]),
-    emqtt:publish(C1, <<"retained/1">>, <<"this is a retained message 1">>, [{qos, 0}, {retain, true}]),
-    emqtt:publish(C1, <<"retained/a/b/c">>, <<"this is a retained message 2">>, [{qos, 0}, {retain, true}]),
+    emqtt:publish(
+      C1, <<"retained/0">>,
+      <<"this is a retained message 0">>,
+      [{qos, 0}, {retain, true}]),
+    emqtt:publish(
+      C1, <<"retained/1">>,
+      <<"this is a retained message 1">>,
+      [{qos, 0}, {retain, true}]),
+    emqtt:publish(
+      C1, <<"retained/a/b/c">>,
+      <<"this is a retained message 2">>,
+      [{qos, 0}, {retain, true}]),
 
     {ok, #{}, [0]} = emqtt:subscribe(C1,  <<"retained/+">>, 0),
     {ok, #{}, [0]} = emqtt:subscribe(C1,  <<"retained/+/b/#">>, 0),
@@ -165,11 +180,26 @@ t_message_expiry(_) ->
     {ok, C1} = emqtt:start_link([{clean_start, true}, {proto_ver, v5}]),
     {ok, _} = emqtt:connect(C1),
 
-    emqtt:publish(C1, <<"retained/0">>, #{'Message-Expiry-Interval' => 0}, <<"don't expire">>, [{qos, 0}, {retain, true}]),
-    emqtt:publish(C1, <<"retained/1">>, #{'Message-Expiry-Interval' => 2}, <<"expire">>, [{qos, 0}, {retain, true}]),
-    emqtt:publish(C1, <<"retained/2">>, #{'Message-Expiry-Interval' => 5}, <<"don't expire">>, [{qos, 0}, {retain, true}]),
-    emqtt:publish(C1, <<"retained/3">>, <<"don't expire">>, [{qos, 0}, {retain, true}]),
-    emqtt:publish(C1, <<"$SYS/retained/4">>, <<"don't expire">>, [{qos, 0}, {retain, true}]),
+    emqtt:publish(
+      C1, <<"retained/0">>, #{'Message-Expiry-Interval' => 0},
+      <<"don't expire">>,
+      [{qos, 0}, {retain, true}]),
+    emqtt:publish(
+      C1, <<"retained/1">>, #{'Message-Expiry-Interval' => 2},
+      <<"expire">>,
+      [{qos, 0}, {retain, true}]),
+    emqtt:publish(
+      C1, <<"retained/2">>, #{'Message-Expiry-Interval' => 5},
+      <<"don't expire">>,
+      [{qos, 0}, {retain, true}]),
+    emqtt:publish(
+      C1, <<"retained/3">>,
+      <<"don't expire">>,
+      [{qos, 0}, {retain, true}]),
+    emqtt:publish(
+      C1, <<"$SYS/retained/4">>,
+      <<"don't expire">>,
+      [{qos, 0}, {retain, true}]),
 
     {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained/+">>, 0),
     {ok, #{}, [0]} = emqtt:subscribe(C1, <<"$SYS/retained/+">>, 0),
@@ -210,9 +240,18 @@ t_message_expiry_2(_) ->
 t_clean(_) ->
     {ok, C1} = emqtt:start_link([{clean_start, true}, {proto_ver, v5}]),
     {ok, _} = emqtt:connect(C1),
-    emqtt:publish(C1, <<"retained/0">>, <<"this is a retained message 0">>, [{qos, 0}, {retain, true}]),
-    emqtt:publish(C1, <<"retained/1">>, <<"this is a retained message 1">>, [{qos, 0}, {retain, true}]),
-    emqtt:publish(C1, <<"retained/test/0">>, <<"this is a retained message 2">>, [{qos, 0}, {retain, true}]),
+    emqtt:publish(
+      C1, <<"retained/0">>,
+      <<"this is a retained message 0">>,
+      [{qos, 0}, {retain, true}]),
+    emqtt:publish(
+      C1, <<"retained/1">>,
+      <<"this is a retained message 1">>,
+      [{qos, 0}, {retain, true}]),
+    emqtt:publish(
+      C1, <<"retained/test/0">>,
+      <<"this is a retained message 2">>,
+      [{qos, 0}, {retain, true}]),
     {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained/#">>, [{qos, 0}, {rh, 0}]),
     ?assertEqual(3, length(receive_messages(3))),
 
@@ -227,7 +266,11 @@ t_stop_publish_clear_msg(_) ->
     emqx_retainer:update_config(#{<<"stop_publish_clear_msg">> => true}),
     {ok, C1} = emqtt:start_link([{clean_start, true}, {proto_ver, v5}]),
     {ok, _} = emqtt:connect(C1),
-    emqtt:publish(C1, <<"retained/0">>, <<"this is a retained message 0">>, [{qos, 0}, {retain, true}]),
+    emqtt:publish(
+      C1, <<"retained/0">>,
+      <<"this is a retained message 0">>,
+      [{qos, 0}, {retain, true}]
+     ),
 
     {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained/#">>, [{qos, 0}, {rh, 0}]),
     ?assertEqual(1, length(receive_messages(1))),
@@ -239,14 +282,27 @@ t_stop_publish_clear_msg(_) ->
     ok = emqtt:disconnect(C1).
 
 t_flow_control(_) ->
-    emqx_retainer:update_config(#{<<"flow_control">> => #{<<"max_read_number">> => 1,
-                                                          <<"msg_deliver_quota">> => 1,
-                                                          <<"quota_release_interval">> => <<"1s">>}}),
+    emqx_retainer:update_config(#{<<"flow_control">> =>
+                                  #{<<"max_read_number">> => 1,
+                                    <<"msg_deliver_quota">> => 1,
+                                    <<"quota_release_interval">> => <<"1s">>}}),
     {ok, C1} = emqtt:start_link([{clean_start, true}, {proto_ver, v5}]),
     {ok, _} = emqtt:connect(C1),
-    emqtt:publish(C1, <<"retained/0">>, <<"this is a retained message 0">>, [{qos, 0}, {retain, true}]),
-    emqtt:publish(C1, <<"retained/1">>, <<"this is a retained message 1">>, [{qos, 0}, {retain, true}]),
-    emqtt:publish(C1, <<"retained/3">>, <<"this is a retained message 3">>, [{qos, 0}, {retain, true}]),
+    emqtt:publish(
+      C1, <<"retained/0">>,
+      <<"this is a retained message 0">>,
+      [{qos, 0}, {retain, true}]
+     ),
+    emqtt:publish(
+      C1, <<"retained/1">>,
+      <<"this is a retained message 1">>,
+      [{qos, 0}, {retain, true}]
+     ),
+    emqtt:publish(
+      C1, <<"retained/3">>,
+      <<"this is a retained message 3">>,
+      [{qos, 0}, {retain, true}]
+     ),
     Begin = erlang:system_time(millisecond),
     {ok, #{}, [0]} = emqtt:subscribe(C1, <<"retained/#">>, [{qos, 0}, {rh, 0}]),
     ?assertEqual(3, length(receive_messages(3))),
diff --git a/apps/emqx_retainer/test/emqx_retainer_mqtt_v5_SUITE.erl b/apps/emqx_retainer/test/emqx_retainer_mqtt_v5_SUITE.erl
index 9a887d2d3..c5c828e55 100644
--- a/apps/emqx_retainer/test/emqx_retainer_mqtt_v5_SUITE.erl
+++ b/apps/emqx_retainer/test/emqx_retainer_mqtt_v5_SUITE.erl
@@ -94,13 +94,23 @@ t_publish_retain_message(_) ->
 
     {ok, Client1} = emqtt:start_link([{proto_ver, v5}]),
     {ok, _} = emqtt:connect(Client1),
-    {ok, _} = emqtt:publish(Client1, Topic, #{}, <<"retained message">>, [{qos, 2}, {retain, true}]),
-    {ok, _} = emqtt:publish(Client1, Topic, #{}, <<"new retained message">>, [{qos, 2}, {retain, true}]),
-    {ok, _} = emqtt:publish(Client1, Topic, #{}, <<"not retained message">>, [{qos, 2}, {retain, false}]),
+    {ok, _} = emqtt:publish(
+                Client1, Topic, #{},
+                <<"retained message">>,
+                [{qos, 2}, {retain, true}]),
+    {ok, _} = emqtt:publish(
+                Client1, Topic, #{},
+                <<"new retained message">>,
+                [{qos, 2}, {retain, true}]),
+    {ok, _} = emqtt:publish(
+                Client1, Topic, #{},
+                <<"not retained message">>,
+                [{qos, 2}, {retain, false}]),
     {ok, _, [2]} = emqtt:subscribe(Client1, Topic, 2),
 
     [Msg] = receive_messages(1),
-    ?assertEqual(<<"new retained message">>, maps:get(payload, Msg)),   %% [MQTT-3.3.1-5] [MQTT-3.3.1-8]
+    %% [MQTT-3.3.1-5] [MQTT-3.3.1-8]
+    ?assertEqual(<<"new retained message">>, maps:get(payload, Msg)),
 
     {ok, _, [0]} = emqtt:unsubscribe(Client1, Topic),
     {ok, _} = emqtt:publish(Client1, Topic, #{}, <<"">>, [{qos, 2}, {retain, true}]),
@@ -113,16 +123,33 @@ t_publish_retain_message(_) ->
 t_publish_message_expiry_interval(_) ->
     {ok, Client1} = emqtt:start_link([{proto_ver, v5}]),
     {ok, _} = emqtt:connect(Client1),
-    {ok, _} = emqtt:publish(Client1, <<"topic/A">>, #{'Message-Expiry-Interval' => 1}, <<"retained message">>, [{qos, 1}, {retain, true}]),
-    {ok, _} = emqtt:publish(Client1, <<"topic/B">>, #{'Message-Expiry-Interval' => 1}, <<"retained message">>, [{qos, 2}, {retain, true}]),
-    {ok, _} = emqtt:publish(Client1, <<"topic/C">>, #{'Message-Expiry-Interval' => 10}, <<"retained message">>, [{qos, 1}, {retain, true}]),
-    {ok, _} = emqtt:publish(Client1, <<"topic/D">>, #{'Message-Expiry-Interval' => 10}, <<"retained message">>, [{qos, 2}, {retain, true}]),
+    {ok, _} = emqtt:publish(
+                Client1, <<"topic/A">>, #{'Message-Expiry-Interval' => 1},
+                <<"retained message">>,
+                [{qos, 1}, {retain, true}]),
+    {ok, _} = emqtt:publish(
+                Client1, <<"topic/B">>, #{'Message-Expiry-Interval' => 1},
+                <<"retained message">>,
+                [{qos, 2}, {retain, true}]),
+    {ok, _} = emqtt:publish(
+                Client1, <<"topic/C">>, #{'Message-Expiry-Interval' => 10},
+                <<"retained message">>,
+                [{qos, 1}, {retain, true}]),
+    {ok, _} = emqtt:publish(
+                Client1, <<"topic/D">>, #{'Message-Expiry-Interval' => 10},
+                <<"retained message">>,
+                [{qos, 2}, {retain, true}]),
     timer:sleep(1500),
     {ok, _, [2]} = emqtt:subscribe(Client1, <<"topic/+">>, 2),
     Msgs = receive_messages(4),
     ?assertEqual(2, length(Msgs)),  %% [MQTT-3.3.2-5]
 
-    L = lists:map(fun(Msg) -> MessageExpiryInterval = maps:get('Message-Expiry-Interval', maps:get(properties, Msg)), MessageExpiryInterval < 10 end, Msgs), 
+    L = lists:map(
+          fun(Msg) ->
+            MessageExpiryInterval = maps:get('Message-Expiry-Interval',
+                                             maps:get(properties, Msg)),
+            MessageExpiryInterval < 10
+          end, Msgs),
     ?assertEqual(2, length(L)),  %% [MQTT-3.3.2-6]
 
     ok = emqtt:disconnect(Client1),
@@ -137,9 +164,21 @@ t_publish_message_expiry_interval(_) ->
 t_subscribe_retain_handing(_) ->
     {ok, Client1} = emqtt:start_link([{proto_ver, v5}]),
     {ok, _} = emqtt:connect(Client1),
-    ok = emqtt:publish(Client1, <<"topic/A">>, #{}, <<"retained message">>, [{qos, 0}, {retain, true}]),
-    {ok, _} = emqtt:publish(Client1, <<"topic/B">>, #{}, <<"retained message">>, [{qos, 1}, {retain, true}]),
-    {ok, _} = emqtt:publish(Client1, <<"topic/C">>, #{}, <<"retained message">>, [{qos, 2}, {retain, true}]),
+    ok = emqtt:publish(
+           Client1, <<"topic/A">>, #{},
+           <<"retained message">>,
+           [{qos, 0}, {retain, true}]
+          ),
+    {ok, _} = emqtt:publish(
+                Client1, <<"topic/B">>, #{},
+                <<"retained message">>,
+                [{qos, 1}, {retain, true}]
+               ),
+    {ok, _} = emqtt:publish(
+                Client1, <<"topic/C">>, #{},
+                <<"retained message">>,
+                [{qos, 2}, {retain, true}]
+               ),
 
     {ok, _, [2]} = emqtt:subscribe(Client1, #{}, [{<<"topic/+">>, [{rh, 1}, {qos, 2}]}]),
     ?assertEqual(3, length(receive_messages(3))),   %% [MQTT-3.3.1-10]
diff --git a/apps/emqx_slow_subs/src/emqx_slow_subs.erl b/apps/emqx_slow_subs/src/emqx_slow_subs.erl
index 370f250fb..027b304b1 100644
--- a/apps/emqx_slow_subs/src/emqx_slow_subs.erl
+++ b/apps/emqx_slow_subs/src/emqx_slow_subs.erl
@@ -104,7 +104,8 @@ on_stats_update(#{clientid := ClientId,
     case ets:lookup(?TOPK_TAB, LastIndex) of
         [#top_k{index = Index}] ->
             %% if last value == the new value, update the type and last_update_time
-            %% XXX for clients whose latency are stable for a long time, is it possible to reduce updates?
+            %% XXX for clients whose latency are stable for a long time, is it
+            %% possible to reduce updates?
             ets:insert(?TOPK_TAB,
                        #top_k{index = Index, type = Type, last_update_time = Ts});
         [_] ->
diff --git a/apps/emqx_slow_subs/src/emqx_slow_subs_api.erl b/apps/emqx_slow_subs/src/emqx_slow_subs_api.erl
index 5ad7e207b..ee2016268 100644
--- a/apps/emqx_slow_subs/src/emqx_slow_subs_api.erl
+++ b/apps/emqx_slow_subs/src/emqx_slow_subs_api.erl
@@ -72,11 +72,16 @@ schema("/slow_subscriptions/settings") ->
      }.
 
 fields(record) ->
-    [
-     {clientid, mk(string(), #{desc => <<"the clientid">>})},
-     {latency, mk(integer(), #{desc => <<"average time for message delivery or time for message expire">>})},
-     {type, mk(string(), #{desc => <<"type of the latency, could be average or expire">>})},
-     {last_update_time, mk(integer(), #{desc => <<"the timestamp of last update">>})}
+    [ {clientid,
+       mk(string(), #{desc => <<"the clientid">>})},
+      {latency,
+       mk(integer(),
+          #{desc => <<"average time for message delivery or time for message expire">>})},
+      {type,
+       mk(string(),
+          #{desc => <<"type of the latency, could be average or expire">>})},
+      {last_update_time,
+       mk(integer(), #{desc => <<"the timestamp of last update">>})}
     ].
 
 conf_schema() ->
diff --git a/apps/emqx_slow_subs/src/emqx_slow_subs_schema.erl b/apps/emqx_slow_subs/src/emqx_slow_subs_schema.erl
index 4a802eb4c..2eca0e730 100644
--- a/apps/emqx_slow_subs/src/emqx_slow_subs_schema.erl
+++ b/apps/emqx_slow_subs/src/emqx_slow_subs_schema.erl
@@ -23,8 +23,8 @@ fields("slow_subs") ->
     , {notice_interval,
        sc(emqx_schema:duration_ms(),
           "0s",
-          "The interval for pushing statistics table records to the system topic. When set to 0, push is disabled"
-          "publish topk list to $SYS/brokers/${node}/slow_subs per notice_interval"
+          "The interval for pushing statistics table records to the system topic. "
+          "publish topk list to $SYS/brokers/${node}/slow_subs per notice_interval. "
           "publish is disabled if set to 0s."
          )}
     , {notice_qos,

From 6e0a2485552738623668f444ccff65d502f9245c Mon Sep 17 00:00:00 2001
From: JianBo He <heeejianbo@gmail.com>
Date: Wed, 12 Jan 2022 19:04:08 +0800
Subject: [PATCH 7/7] chore: add namespace for _schema.erl module

---
 apps/emqx/src/emqx_limiter/src/emqx_limiter_schema.erl | 5 ++++-
 apps/emqx_retainer/src/emqx_retainer_schema.erl        | 4 +++-
 apps/emqx_slow_subs/src/emqx_slow_subs_schema.erl      | 4 +++-
 3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/apps/emqx/src/emqx_limiter/src/emqx_limiter_schema.erl b/apps/emqx/src/emqx_limiter/src/emqx_limiter_schema.erl
index 91936c8f0..5bee4ed93 100644
--- a/apps/emqx/src/emqx_limiter/src/emqx_limiter_schema.erl
+++ b/apps/emqx/src/emqx_limiter/src/emqx_limiter_schema.erl
@@ -19,7 +19,8 @@
 -include_lib("typerefl/include/types.hrl").
 
 -export([ roots/0, fields/1, to_rate/1, to_capacity/1
-        , minimum_period/0, to_burst_rate/1, to_initial/1]).
+        , minimum_period/0, to_burst_rate/1, to_initial/1
+        , namespace/0]).
 
 -define(KILOBYTE, 1024).
 
@@ -56,6 +57,8 @@
 
 -import(emqx_schema, [sc/2, map/2]).
 
+namespace() -> limiter.
+
 roots() -> [limiter].
 
 fields(limiter) ->
diff --git a/apps/emqx_retainer/src/emqx_retainer_schema.erl b/apps/emqx_retainer/src/emqx_retainer_schema.erl
index 308fc528f..f4c1e54e5 100644
--- a/apps/emqx_retainer/src/emqx_retainer_schema.erl
+++ b/apps/emqx_retainer/src/emqx_retainer_schema.erl
@@ -2,10 +2,12 @@
 
 -include_lib("typerefl/include/types.hrl").
 
--export([roots/0, fields/1]).
+-export([roots/0, fields/1, namespace/0]).
 
 -define(TYPE(Type), hoconsc:mk(Type)).
 
+namespace() -> "retainer".
+
 roots() -> ["retainer"].
 
 fields("retainer") ->
diff --git a/apps/emqx_slow_subs/src/emqx_slow_subs_schema.erl b/apps/emqx_slow_subs/src/emqx_slow_subs_schema.erl
index 2eca0e730..7a1b57d0b 100644
--- a/apps/emqx_slow_subs/src/emqx_slow_subs_schema.erl
+++ b/apps/emqx_slow_subs/src/emqx_slow_subs_schema.erl
@@ -2,7 +2,9 @@
 
 -include_lib("typerefl/include/types.hrl").
 
--export([roots/0, fields/1]).
+-export([roots/0, fields/1, namespace/0]).
+
+namespace() -> "slow_subs".
 
 roots() -> ["slow_subs"].