Merge pull request #9139 from lafirest/fix/clean_blocked_user_data

feat(banned): clean retained/delayed data when client is banned

CHANGES-5.0.md

@@ -9,6 +9,7 @@
   Prior to this fix, the message publish APIs (`api/v5/publish` and `api/v5/publish/bulk`) echos the message back to the client in HTTP body.
   This change fixed it to only send back the message ID.
 * Add /trace/:name/log_detail HTTP API to return trace file's size and mtime [#9152](https://github.com/emqx/emqx/pull/9152)
+* Allow clear retained/delayed data when client is banned.[#9139](https://github.com/emqx/emqx/pull/9139)
 
 ## Bug fixes
 

apps/emqx/i18n/emqx_schema_i18n.conf

@@ -495,6 +495,19 @@ emqx_schema {
     }
   }
 
+  flapping_detect_clean_when_banned {
+    desc {
+        en: "Clean retained/delayed messages when client is banned.\n"
+            "Note: This may be expensive and only supports users banned by clientid."
+        zh: "当客户端被禁时删除其保留、延迟消息"
+            "注意: 这个操作开销可能较大,且只支持通过 clientid 封禁的用户数据。"
+    }
+    label: {
+        en: "Clean when banned"
+        zh: "被禁时清理消息"
+    }
+  }
+
   persistent_session_store_enabled {
     desc {
         en: "Use the database to store information about persistent sessions.\n"

apps/emqx/priv/bpapi.versions

@@ -9,6 +9,7 @@
 {emqx_conf,2}.
 {emqx_dashboard,1}.
 {emqx_delayed,1}.
+{emqx_delayed,2}.
 {emqx_exhook,1}.
 {emqx_gateway_api_listeners,1}.
 {emqx_gateway_cm,1}.

apps/emqx/src/emqx_banned.erl

@@ -32,11 +32,13 @@
 -export([
     check/1,
     create/1,
+    create/2,
     look_up/1,
     delete/1,
     info/1,
     format/1,
-    parse/1
+    parse/1,
+    parse_opts/1
 ]).
 
 %% gen_server callbacks
@@ -63,6 +65,13 @@
 -compile(nowarn_export_all).
 -endif.
 
+-type banned_opts() :: #{
+    clean => boolean(),
+    atom() => term()
+}.
+
+-export_type([banned_opts/0]).
+
 %%--------------------------------------------------------------------
 %% Mnesia bootstrap
 %%--------------------------------------------------------------------
@@ -141,6 +150,11 @@ parse(Params) ->
                     {error, ErrorReason}
             end
     end.
+
+parse_opts(Params) ->
+    Clean = maps:get(<<"clean">>, Params, false),
+    #{clean => Clean}.
+
 pares_who(#{as := As, who := Who}) ->
     pares_who(#{<<"as">> => As, <<"who">> => Who});
 pares_who(#{<<"as">> := peerhost, <<"who">> := Peerhost0}) ->
@@ -162,13 +176,15 @@ to_rfc3339(Timestamp) ->
 
 -spec create(emqx_types:banned() | map()) ->
     {ok, emqx_types:banned()} | {error, {already_exist, emqx_types:banned()}}.
-create(#{
-    who := Who,
-    by := By,
-    reason := Reason,
-    at := At,
-    until := Until
-}) ->
+create(
+    #{
+        who := Who,
+        by := By,
+        reason := Reason,
+        at := At,
+        until := Until
+    } = Data
+) ->
     Banned = #banned{
         who = Who,
         by = By,
@@ -176,11 +192,16 @@ create(#{
         at = At,
         until = Until
     },
-    create(Banned);
-create(Banned = #banned{who = Who}) ->
+    create(Banned, Data);
+create(Banned = #banned{}) ->
+    create(Banned, #{clean => false}).
+
+-spec create(emqx_types:banned(), banned_opts()) ->
+    {ok, emqx_types:banned()} | {error, {already_exist, emqx_types:banned()}}.
+create(Banned = #banned{who = Who}, Opts) ->
     case look_up(Who) of
         [] ->
-            mria:dirty_write(?BANNED_TAB, Banned),
+            insert_banned(Banned, Opts),
             {ok, Banned};
         [OldBanned = #banned{until = Until}] ->
             %% Don't support shorten or extend the until time by overwrite.
@@ -190,7 +211,7 @@ create(Banned = #banned{who = Who}) ->
                     {error, {already_exist, OldBanned}};
                 %% overwrite expired one is ok.
                 false ->
-                    mria:dirty_write(?BANNED_TAB, Banned),
+                    insert_banned(Banned, Opts),
                     {ok, Banned}
             end
     end.
@@ -266,3 +287,12 @@ expire_banned_items(Now) ->
         ok,
         ?BANNED_TAB
     ).
+
+insert_banned(Banned, Opts) ->
+    mria:dirty_write(?BANNED_TAB, Banned),
+    run_hooks(Banned, Opts).
+
+run_hooks(Banned, #{clean := true}) ->
+    emqx_hooks:run('client.banned', [Banned]);
+run_hooks(_Banned, _Opts) ->
+    ok.

apps/emqx/src/emqx_flapping.erl

@@ -121,7 +121,7 @@ handle_cast(
             started_at = StartedAt,
             detect_cnt = DetectCnt
         },
-        #{window_time := WindTime, ban_time := Interval}},
+        #{window_time := WindTime, ban_time := Interval, clean_when_banned := Clean}},
     State
 ) ->
     case now_diff(StartedAt) < WindTime of
@@ -145,7 +145,7 @@ handle_cast(
                 at = Now,
                 until = Now + (Interval div 1000)
             },
-            {ok, _} = emqx_banned:create(Banned),
+            {ok, _} = emqx_banned:create(Banned, #{clean => Clean}),
             ok;
         false ->
             ?SLOG(

apps/emqx/src/emqx_schema.erl

@@ -640,6 +640,14 @@ fields("flapping_detect") ->
                     default => "5m",
                     desc => ?DESC(flapping_detect_ban_time)
                 }
+            )},
+        {"clean_when_banned",
+            sc(
+                boolean(),
+                #{
+                    default => false,
+                    desc => ?DESC(flapping_detect_clean_when_banned)
+                }
             )}
     ];
 fields("force_shutdown") ->

apps/emqx/test/emqx_flapping_SUITE.erl

@@ -34,7 +34,8 @@ init_per_suite(Config) ->
             % 0.1s
             window_time => 100,
             %% 2s
-            ban_time => 2000
+            ban_time => 2000,
+            clean_when_banned => false
         }
     ),
     Config.

apps/emqx_management/i18n/emqx_mgmt_api_banned_i18n.conf

@@ -95,4 +95,16 @@ emqx_mgmt_api_banned {
             zh: """封禁结束时间"""
         }
     }
+    clean {
+        desc {
+            en: """Clean retained/delayed messages when client is banned."""
+                """Note: This may be expensive and only supports users banned by clientid."""
+            zh: """当客户端被禁时删除其保留、延迟消息"""
+                """注意: 这个操作开销可能较大,且只支持通过 clientid 封禁的用户数据。"""
+        }
+        label {
+            en: """Clean when banned"""
+            zh: """被禁时清理消息"""
+        }
+    }
 }

apps/emqx_management/src/emqx_mgmt_api_banned.erl

@@ -150,6 +150,13 @@ fields(ban) ->
                 desc => ?DESC(until),
                 required => false,
                 example => <<"2021-10-25T21:53:47+08:00">>
+            })},
+        {clean,
+            hoconsc:mk(boolean(), #{
+                desc => ?DESC(clean),
+                required => false,
+                default => false,
+                example => false
             })}
     ].
 
@@ -161,7 +168,8 @@ banned(post, #{body := Body}) ->
         {error, Reason} ->
             {400, 'BAD_REQUEST', list_to_binary(Reason)};
         Ban ->
-            case emqx_banned:create(Ban) of
+            Opts = emqx_banned:parse_opts(Body),
+            case emqx_banned:create(Ban, Opts) of
                 {ok, Banned} ->
                     {200, format(Banned)};
                 {error, {already_exist, Old}} ->

apps/emqx_modules/src/emqx_delayed.erl

@@ -23,6 +23,7 @@
 -include_lib("emqx/include/logger.hrl").
 -include_lib("snabbkaffe/include/snabbkaffe.hrl").
 -include_lib("emqx/include/emqx_hooks.hrl").
+-include_lib("stdlib/include/ms_transform.hrl").
 
 %% Mnesia bootstrap
 -export([mnesia/1]).
@@ -31,7 +32,8 @@
 
 -export([
     start_link/0,
-    on_message_publish/1
+    on_message_publish/1,
+    on_client_banned/1
 ]).
 
 %% gen_server callbacks
@@ -44,7 +46,7 @@
     code_change/3
 ]).
 
-%% gen_server callbacks
+%% API
 -export([
     load/0,
     unload/0,
@@ -57,7 +59,9 @@
     delete_delayed_message/1,
     delete_delayed_message/2,
     cluster_list/1,
-    cluster_query/4
+    cluster_query/4,
+    clean_by_clientid/1,
+    do_clean_by_clientid/1
 ]).
 
 -export([
@@ -138,6 +142,11 @@ on_message_publish(
 on_message_publish(Msg) ->
     {ok, Msg}.
 
+on_client_banned(#banned{who = {clientid, ClientId}}) ->
+    clean_by_clientid(ClientId);
+on_client_banned(_) ->
+    ok.
+
 %%--------------------------------------------------------------------
 %% Start delayed publish server
 %%--------------------------------------------------------------------
@@ -228,7 +237,7 @@ get_delayed_message(Id) ->
 get_delayed_message(Node, Id) when Node =:= node() ->
     get_delayed_message(Id);
 get_delayed_message(Node, Id) ->
-    emqx_delayed_proto_v1:get_delayed_message(Node, Id).
+    emqx_delayed_proto_v2:get_delayed_message(Node, Id).
 
 -spec delete_delayed_message(binary()) -> with_id_return().
 delete_delayed_message(Id) ->
@@ -243,7 +252,7 @@ delete_delayed_message(Id) ->
 delete_delayed_message(Node, Id) when Node =:= node() ->
     delete_delayed_message(Id);
 delete_delayed_message(Node, Id) ->
-    emqx_delayed_proto_v1:delete_delayed_message(Node, Id).
+    emqx_delayed_proto_v2:delete_delayed_message(Node, Id).
 
 update_config(Config) ->
     emqx_conf:update([delayed], Config, #{rawconf_with_defaults => true, override_to => cluster}).
@@ -252,6 +261,15 @@ post_config_update(_KeyPath, _ConfigReq, NewConf, _OldConf, _AppEnvs) ->
     Enable = maps:get(enable, NewConf, undefined),
     load_or_unload(Enable).
 
+clean_by_clientid(ClientId) ->
+    Nodes = mria_mnesia:running_nodes(),
+    emqx_delayed_proto_v2:clean_by_clientid(Nodes, ClientId).
+
+do_clean_by_clientid(ClientId) ->
+    ets:select_delete(
+        ?TAB, ets:fun2ms(fun(#delayed_message{msg = Msg}) -> Msg#message.from =:= ClientId end)
+    ).
+
 %%--------------------------------------------------------------------
 %% gen_server callback
 %%--------------------------------------------------------------------
@@ -383,9 +401,11 @@ delayed_count() -> mnesia:table_info(?TAB, size).
 
 do_load_or_unload(true, State) ->
     emqx_hooks:put('message.publish', {?MODULE, on_message_publish, []}, ?HP_DELAY_PUB),
+    ok = emqx_hooks:put('client.banned', {?MODULE, on_client_banned, []}, ?HP_LOWEST),
     State;
 do_load_or_unload(false, #{publish_timer := PubTimer} = State) ->
     emqx_hooks:del('message.publish', {?MODULE, on_message_publish}),
+    ok = emqx_hooks:del('client.banned', {?MODULE, on_client_banned}),
     emqx_misc:cancel_timer(PubTimer),
     ets:delete_all_objects(?TAB),
     State#{publish_timer := undefined, publish_at := 0};

apps/emqx_modules/src/proto/emqx_delayed_proto_v2.erl

@@ -0,0 +1,47 @@
+%%--------------------------------------------------------------------
+%%Copyright (c) 2022 EMQ Technologies Co., Ltd. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%--------------------------------------------------------------------
+
+-module(emqx_delayed_proto_v2).
+
+-behaviour(emqx_bpapi).
+
+-export([
+    introduced_in/0,
+    get_delayed_message/2,
+    delete_delayed_message/2,
+    clean_by_clientid/2
+]).
+
+-include_lib("emqx/include/bpapi.hrl").
+
+-define(TIMEOUT, 15000).
+
+introduced_in() ->
+    "5.0.9".
+
+-spec get_delayed_message(node(), binary()) ->
+    emqx_delayed:with_id_return(map()) | emqx_rpc:badrpc().
+get_delayed_message(Node, Id) ->
+    rpc:call(Node, emqx_delayed, get_delayed_message, [Id]).
+
+-spec delete_delayed_message(node(), binary()) -> emqx_delayed:with_id_return() | emqx_rpc:badrpc().
+delete_delayed_message(Node, Id) ->
+    rpc:call(Node, emqx_delayed, delete_delayed_message, [Id]).
+
+-spec clean_by_clientid(list(node()), emqx_types:clientid()) ->
+    emqx_rpc:erpc_multicall().
+clean_by_clientid(Nodes, ClientID) ->
+    erpc:multicall(Nodes, emqx_delayed, do_clean_by_clientid, [ClientID], ?TIMEOUT).

apps/emqx_modules/test/emqx_delayed_SUITE.erl

@@ -212,6 +212,67 @@ t_delayed_precision(_) ->
     _ = on_message_publish(DelayedMsg0),
     ?assert(FutureDiff() =< MaxSpan).
 
+t_banned_clean(_) ->
+    emqx:update_config([delayed, max_delayed_messages], 10000),
+    ClientId1 = <<"bc1">>,
+    ClientId2 = <<"bc2">>,
+    {ok, C1} = emqtt:start_link([{clientid, ClientId1}, {clean_start, true}, {proto_ver, v5}]),
+    {ok, _} = emqtt:connect(C1),
+
+    {ok, C2} = emqtt:start_link([{clientid, ClientId2}, {clean_start, true}, {proto_ver, v5}]),
+    {ok, _} = emqtt:connect(C2),
+
+    [
+        begin
+            emqtt:publish(
+                Conn,
+                <<"$delayed/60/0/", ClientId/binary>>,
+                <<"">>,
+                [{qos, 0}, {retain, false}]
+            ),
+            emqtt:publish(
+                Conn,
+                <<"$delayed/60/1/", ClientId/binary>>,
+                <<"">>,
+                [{qos, 0}, {retain, false}]
+            )
+        end
+     || {ClientId, Conn} <- lists:zip([ClientId1, ClientId2], [C1, C2])
+    ],
+
+    emqtt:publish(
+        C2,
+        <<"$delayed/60/2/", ClientId2/binary>>,
+        <<"">>,
+        [{qos, 0}, {retain, false}]
+    ),
+
+    timer:sleep(500),
+    ?assertMatch(#{meta := #{count := 5}}, emqx_delayed:list(#{page => 1, limit => 10})),
+
+    Now = erlang:system_time(second),
+    Who = {clientid, ClientId2},
+    try
+        emqx_banned:create(#{
+            who => Who,
+            by => <<"test">>,
+            reason => <<"test">>,
+            at => Now,
+            until => Now + 120,
+            clean => true
+        }),
+
+        timer:sleep(500),
+
+        ?assertMatch(#{meta := #{count := 2}}, emqx_delayed:list(#{page => 1, limit => 10}))
+    after
+        emqx_banned:delete(Who),
+        emqx_delayed:clean_by_clientid(ClientId1)
+    end,
+    timer:sleep(500),
+    ok = emqtt:disconnect(C1),
+    ok = emqtt:disconnect(C2).
+
 subscribe_proc() ->
     Self = self(),
     Ref = erlang:make_ref(),

apps/emqx_retainer/src/emqx_retainer.app.src

@@ -2,7 +2,7 @@
 {application, emqx_retainer, [
     {description, "EMQX Retainer"},
     % strict semver, bump manually!
-    {vsn, "5.0.5"},
+    {vsn, "5.0.6"},
     {modules, []},
     {registered, [emqx_retainer_sup]},
     {applications, [kernel, stdlib, emqx]},

apps/emqx_retainer/src/emqx_retainer.erl

@@ -19,6 +19,7 @@
 -behaviour(gen_server).
 
 -include("emqx_retainer.hrl").
+-include_lib("emqx/include/emqx.hrl").
 -include_lib("emqx/include/logger.hrl").
 -include_lib("emqx/include/emqx_hooks.hrl").
 
@@ -26,7 +27,8 @@
 
 -export([
     on_session_subscribed/4,
-    on_message_publish/2
+    on_message_publish/2,
+    on_client_banned/1
 ]).
 
 -export([
@@ -39,6 +41,7 @@
     get_expiry_time/1,
     update_config/1,
     clean/0,
+    clean_by_clientid/1,
     delete/1,
     page_read/3,
     post_config_update/5,
@@ -80,6 +83,7 @@
 -callback match_messages(context(), topic(), cursor()) -> {ok, list(), cursor()}.
 -callback clear_expired(context()) -> ok.
 -callback clean(context()) -> ok.
+-callback clean_by_clientid(context(), emqx_types:clientid()) -> ok.
 -callback size(context()) -> non_neg_integer().
 
 %%--------------------------------------------------------------------
@@ -118,6 +122,11 @@ on_message_publish(Msg = #message{flags = #{retain := true}}, Context) ->
 on_message_publish(Msg, _) ->
     {ok, Msg}.
 
+on_client_banned(#banned{who = {clientid, ClientId}}) ->
+    clean_by_clientid(ClientId);
+on_client_banned(_) ->
+    ok.
+
 %%--------------------------------------------------------------------
 %% APIs
 %%--------------------------------------------------------------------
@@ -151,6 +160,9 @@ update_config(Conf) ->
 clean() ->
     call(?FUNCTION_NAME).
 
+clean_by_clientid(ClientId) ->
+    call({?FUNCTION_NAME, ClientId}).
+
 delete(Topic) ->
     call({?FUNCTION_NAME, Topic}).
 
@@ -207,6 +219,9 @@ handle_call({update_config, NewConf, OldConf}, _, State) ->
 handle_call(clean, _, #{context := Context} = State) ->
     clean(Context),
     {reply, ok, State};
+handle_call({clean_by_clientid, ClientId}, _, #{context := Context} = State) ->
+    clean_by_clientid(Context, ClientId),
+    {reply, ok, State};
 handle_call({delete, Topic}, _, #{context := Context} = State) ->
     delete_message(Context, Topic),
     {reply, ok, State};
@@ -298,6 +313,11 @@ clean(Context) ->
     Mod = get_backend_module(),
     Mod:clean(Context).
 
+-spec clean_by_clientid(context(), emqx_types:clientid()) -> ok.
+clean_by_clientid(Context, ClientId) ->
+    Mod = get_backend_module(),
+    Mod:clean_by_clientid(Context, ClientId).
+
 -spec update_config(state(), hocons:config(), hocons:config()) -> state().
 update_config(State, Conf, OldConf) ->
     update_config(
@@ -433,11 +453,13 @@ load(Context) ->
         'session.subscribed', {?MODULE, on_session_subscribed, [Context]}, ?HP_RETAINER
     ),
     ok = emqx_hooks:put('message.publish', {?MODULE, on_message_publish, [Context]}, ?HP_RETAINER),
+    ok = emqx_hooks:put('client.banned', {?MODULE, on_client_banned, []}, ?HP_LOWEST),
     emqx_stats:update_interval(emqx_retainer_stats, fun ?MODULE:stats_fun/0),
     ok.
 
 unload() ->
     ok = emqx_hooks:del('message.publish', {?MODULE, on_message_publish}),
     ok = emqx_hooks:del('session.subscribed', {?MODULE, on_session_subscribed}),
+    ok = emqx_hooks:del('client.banned', {?MODULE, on_client_banned}),
     emqx_stats:cancel_update(emqx_retainer_stats),
     ok.

apps/emqx_retainer/src/emqx_retainer_mnesia.erl

@@ -33,13 +33,14 @@
     match_messages/3,
     clear_expired/1,
     clean/1,
+    clean_by_clientid/2,
     size/1
 ]).
 
 %% Internal exports (RPC)
 -export([
     do_store_retained/1,
-    do_clear_expired/0,
+    do_clear/1,
     do_delete_message/1,
     do_populate_index_meta/1,
     do_reindex_batch/2
@@ -61,6 +62,8 @@
 -record(retained_index, {key, expiry_time}).
 -record(retained_index_meta, {key, read_indices, write_indices, reindexing, extra}).
 
+-type retained_message() :: #retained_message{}.
+
 -define(META_KEY, index_meta).
 
 -define(CLEAR_BATCH_SIZE, 1000).
@@ -164,18 +167,22 @@ do_store_retained(#message{topic = Topic} = Msg) ->
     end.
 
 clear_expired(_) ->
-    {atomic, _} = mria:transaction(?RETAINER_SHARD, fun ?MODULE:do_clear_expired/0),
+    NowMs = erlang:system_time(millisecond),
+    {atomic, _} = mria:transaction(?RETAINER_SHARD, fun ?MODULE:do_clear/1, [
+        fun(
+            #retained_message{expiry_time = ExpiryTime}
+        ) ->
+            (ExpiryTime =/= 0) and (ExpiryTime < NowMs)
+        end
+    ]),
     ok.
 
-do_clear_expired() ->
-    NowMs = erlang:system_time(millisecond),
+-spec do_clear(fun((retained_message()) -> boolean())) -> ok.
+do_clear(Pred) ->
     QH = qlc:q([
         TopicTokens
-     || #retained_message{
-            topic = TopicTokens,
-            expiry_time = ExpiryTime
-        } <- mnesia:table(?TAB_MESSAGE, [{lock, write}]),
-        (ExpiryTime =/= 0) and (ExpiryTime < NowMs)
+     || #retained_message{topic = TopicTokens} = Data <- mnesia:table(?TAB_MESSAGE, [{lock, write}]),
+        Pred(Data)
     ]),
     QC = qlc:cursor(QH),
     clear_batch(db_indices(write), QC).
@@ -263,6 +270,14 @@ clean(_) ->
     _ = mria:clear_table(?TAB_INDEX),
     ok.
 
+clean_by_clientid(_, ClientId) ->
+    {atomic, _} = mria:transaction(?RETAINER_SHARD, fun ?MODULE:do_clear/1, [
+        fun(Msg) ->
+            Msg#retained_message.msg#message.from =:= ClientId
+        end
+    ]),
+    ok.
+
 size(_) ->
     table_size().
 

apps/emqx_retainer/test/emqx_retainer_SUITE.erl

@@ -626,6 +626,66 @@ t_get_basic_usage_info(_Config) ->
     ?assertEqual(#{retained_messages => 5}, emqx_retainer:get_basic_usage_info()),
     ok.
 
+t_banned_clean(_) ->
+    ClientId1 = <<"bc1">>,
+    ClientId2 = <<"bc2">>,
+    {ok, C1} = emqtt:start_link([{clientid, ClientId1}, {clean_start, true}, {proto_ver, v5}]),
+    {ok, _} = emqtt:connect(C1),
+
+    {ok, C2} = emqtt:start_link([{clientid, ClientId2}, {clean_start, true}, {proto_ver, v5}]),
+    {ok, _} = emqtt:connect(C2),
+
+    [
+        begin
+            emqtt:publish(
+                Conn,
+                <<"bc/0/", ClientId/binary>>,
+                <<"this is a retained message 0">>,
+                [{qos, 0}, {retain, true}]
+            ),
+            emqtt:publish(
+                Conn,
+                <<"bc/1/", ClientId/binary>>,
+                <<"this is a retained message 1">>,
+                [{qos, 0}, {retain, true}]
+            )
+        end
+     || {ClientId, Conn} <- lists:zip([ClientId1, ClientId2], [C1, C2])
+    ],
+
+    emqtt:publish(
+        C2,
+        <<"bc/2/", ClientId2/binary>>,
+        <<"this is a retained message 2">>,
+        [{qos, 0}, {retain, true}]
+    ),
+
+    timer:sleep(500),
+    {ok, List} = emqx_retainer:page_read(<<"bc/+/+">>, 1, 10),
+    ?assertEqual(5, length(List)),
+
+    Now = erlang:system_time(second),
+    Who = {clientid, ClientId2},
+    emqx_banned:create(#{
+        who => Who,
+        by => <<"test">>,
+        reason => <<"test">>,
+        at => Now,
+        until => Now + 120,
+        clean => true
+    }),
+
+    timer:sleep(500),
+
+    {ok, List2} = emqx_retainer:page_read(<<"bc/#">>, 1, 10),
+    ?assertEqual(2, length(List2)),
+
+    emqx_banned:delete(Who),
+    emqx_retainer:clean(),
+    timer:sleep(500),
+    ok = emqtt:disconnect(C1),
+    ok = emqtt:disconnect(C2).
+
 %% test whether the app can start normally after disabling emqx_retainer
 %% fix: https://github.com/emqx/emqx/pull/8911
 test_disable_then_start(_Config) ->