From 3bc419ee64a33b9ee01ddff47075dc41ed64909a Mon Sep 17 00:00:00 2001
From: Stefan Strigler <stefan.strigler@emqx.io>
Date: Thu, 6 Jul 2023 15:25:50 +0200
Subject: [PATCH 1/6] fix(emqx_gateway): return 404 for unknown listener id

---
 apps/emqx_gateway/src/emqx_gateway_api_listeners.erl |  9 +++++++--
 apps/emqx_gateway/src/emqx_gateway_http.erl          |  2 +-
 apps/emqx_gateway/test/emqx_gateway_api_SUITE.erl    | 11 +++++++++++
 3 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/apps/emqx_gateway/src/emqx_gateway_api_listeners.erl b/apps/emqx_gateway/src/emqx_gateway_api_listeners.erl
index e62923bc2..046e23300 100644
--- a/apps/emqx_gateway/src/emqx_gateway_api_listeners.erl
+++ b/apps/emqx_gateway/src/emqx_gateway_api_listeners.erl
@@ -112,8 +112,13 @@ listeners(post, #{bindings := #{name := Name0}, body := LConf}) ->
 
 listeners_insta(delete, #{bindings := #{name := Name0, id := ListenerId}}) ->
     with_gateway(Name0, fun(_GwName, _) ->
-        ok = emqx_gateway_http:remove_listener(ListenerId),
-        {204}
+        case emqx_gateway_conf:listener(ListenerId) of
+            {ok, _Listener} ->
+                ok = emqx_gateway_http:remove_listener(ListenerId),
+                {204};
+            {error, not_found} ->
+                return_http_error(404, "Listener not found")
+        end
     end);
 listeners_insta(get, #{bindings := #{name := Name0, id := ListenerId}}) ->
     with_gateway(Name0, fun(_GwName, _) ->
diff --git a/apps/emqx_gateway/src/emqx_gateway_http.erl b/apps/emqx_gateway/src/emqx_gateway_http.erl
index 58c201c75..2186ac3d7 100644
--- a/apps/emqx_gateway/src/emqx_gateway_http.erl
+++ b/apps/emqx_gateway/src/emqx_gateway_http.erl
@@ -550,7 +550,7 @@ with_gateway(GwName0, Fun) ->
             return_http_error(400, [K, " is required"]);
         %% Exceptions from emqx_gateway_utils:parse_listener_id/1
         error:{invalid_listener_id, Id} ->
-            return_http_error(400, ["Invalid listener id: ", Id]);
+            return_http_error(404, ["Listener not found: ", Id]);
         %% Exceptions from emqx:get_config/1
         error:{config_not_found, Path0} ->
             Path = lists:concat(
diff --git a/apps/emqx_gateway/test/emqx_gateway_api_SUITE.erl b/apps/emqx_gateway/test/emqx_gateway_api_SUITE.erl
index f1cfd26d0..e486c8c16 100644
--- a/apps/emqx_gateway/test/emqx_gateway_api_SUITE.erl
+++ b/apps/emqx_gateway/test/emqx_gateway_api_SUITE.erl
@@ -409,6 +409,7 @@ t_listeners_tcp(_) ->
 
     {204, _} = request(delete, "/gateways/stomp/listeners/stomp:tcp:def"),
     {404, _} = request(get, "/gateways/stomp/listeners/stomp:tcp:def"),
+    {404, _} = request(delete, "/gateways/stomp/listeners/stomp:tcp:def"),
     ok.
 
 t_listeners_max_conns(_) ->
@@ -480,9 +481,19 @@ t_listeners_authn(_) ->
     {200, ConfResp3} = request(get, Path),
     assert_confs(AuthConf2, ConfResp3),
 
+    {404, _} = request(get, Path ++ "/users/not_exists"),
+    {404, _} = request(delete, Path ++ "/users/not_exists"),
+
     {204, _} = request(delete, Path),
     %% FIXME: 204?
     {204, _} = request(get, Path),
+
+    BadPath = "/gateways/stomp/listeners/stomp:tcp:not_exists/authentication/users/foo",
+    {404, _} = request(get, BadPath),
+    {404, _} = request(delete, BadPath),
+
+    {404, _} = request(get, "/gateways/stomp/listeners/not_exists"),
+    {404, _} = request(delete, "/gateways/stomp/listeners/not_exists"),
     ok.
 
 t_listeners_authn_data_mgmt(_) ->

From d65d690c175fe3e8cdc11a2d6eaa53c392654bb4 Mon Sep 17 00:00:00 2001
From: Stefan Strigler <stefan.strigler@emqx.io>
Date: Thu, 6 Jul 2023 15:26:15 +0200
Subject: [PATCH 2/6] fix(emqx_gateway): return 404 for unknown client id

---
 .../src/emqx_gateway_api_clients.erl          | 48 +++++++++++++++++--
 .../test/emqx_gateway_api_SUITE.erl           | 41 ++++++++++++++++
 .../test/emqx_gateway_cli_SUITE.erl           | 16 +------
 .../test/emqx_gateway_test_utils.erl          | 16 +++++++
 4 files changed, 102 insertions(+), 19 deletions(-)

diff --git a/apps/emqx_gateway/src/emqx_gateway_api_clients.erl b/apps/emqx_gateway/src/emqx_gateway_api_clients.erl
index 8037f4197..8cfcb70e6 100644
--- a/apps/emqx_gateway/src/emqx_gateway_api_clients.erl
+++ b/apps/emqx_gateway/src/emqx_gateway_api_clients.erl
@@ -57,7 +57,8 @@
     qs2ms/2,
     run_fuzzy_filter/2,
     format_channel_info/1,
-    format_channel_info/2
+    format_channel_info/2,
+    client_info_mountpoint/1
 ]).
 
 -define(TAGS, [<<"Gateway Clients">>]).
@@ -177,8 +178,12 @@ clients_insta(delete, #{
     }
 }) ->
     with_gateway(Name0, fun(GwName, _) ->
-        _ = emqx_gateway_http:kickout_client(GwName, ClientId),
-        {204}
+        case emqx_gateway_http:kickout_client(GwName, ClientId) of
+            {error, not_found} ->
+                return_http_error(404, "Client not found");
+            _ ->
+                {204}
+        end
     end).
 
 %% List the established subscriptions with mountpoint
@@ -234,8 +239,13 @@ subscriptions(delete, #{
     }
 }) ->
     with_gateway(Name0, fun(GwName, _) ->
-        _ = emqx_gateway_http:client_unsubscribe(GwName, ClientId, Topic),
-        {204}
+        case lookup_topic(GwName, ClientId, Topic) of
+            {ok, _} ->
+                _ = emqx_gateway_http:client_unsubscribe(GwName, ClientId, Topic),
+                {204};
+            {error, not_found} ->
+                return_http_error(404, "Resource not found")
+        end
     end).
 
 %%--------------------------------------------------------------------
@@ -260,6 +270,34 @@ extra_sub_props(Props) ->
         #{subid => maps:get(<<"subid">>, Props, undefined)}
     ).
 
+lookup_topic(GwName, ClientId, Topic) ->
+    Mountpoints = emqx_gateway_http:lookup_client(
+        GwName,
+        ClientId,
+        {?MODULE, client_info_mountpoint}
+    ),
+    case emqx_gateway_http:list_client_subscriptions(GwName, ClientId) of
+        {ok, Subscriptions} ->
+            case
+                [
+                    S
+                 || S = #{topic := Topic0} <- Subscriptions,
+                    Mountpoint <- Mountpoints,
+                    Topic0 == emqx_mountpoint:mount(Mountpoint, Topic)
+                ]
+            of
+                [] ->
+                    {error, not_found};
+                Filtered ->
+                    {ok, Filtered}
+            end;
+        Error ->
+            Error
+    end.
+
+client_info_mountpoint({_, #{clientinfo := #{mountpoint := Mountpoint}}, _}) ->
+    Mountpoint.
+
 %%--------------------------------------------------------------------
 %% QueryString to MatchSpec
 
diff --git a/apps/emqx_gateway/test/emqx_gateway_api_SUITE.erl b/apps/emqx_gateway/test/emqx_gateway_api_SUITE.erl
index e486c8c16..a3fe39852 100644
--- a/apps/emqx_gateway/test/emqx_gateway_api_SUITE.erl
+++ b/apps/emqx_gateway/test/emqx_gateway_api_SUITE.erl
@@ -586,6 +586,47 @@ t_listeners_authn_data_mgmt(_) ->
 
     ok.
 
+t_clients(_) ->
+    GwConf = #{
+        name => <<"mqttsn">>,
+        gateway_id => 1,
+        broadcast => true,
+        predefined => [#{id => 1, topic => <<"t/a">>}],
+        enable_qos3 => true,
+        listeners => [
+            #{name => <<"def">>, type => <<"udp">>, bind => <<"1884">>}
+        ]
+    },
+    init_gw("mqttsn", GwConf),
+    Path = "/gateways/mqttsn/clients",
+    MyClient = Path ++ "/my_client",
+    MyClientSubscriptions = MyClient ++ "/subscriptions",
+    {200, NoClients} = request(get, Path),
+    ?assertMatch(#{data := []}, NoClients),
+
+    ClientSocket = emqx_gateway_test_utils:sn_client_connect(<<"my_client">>),
+    {200, _} = request(get, MyClient),
+    {200, Clients} = request(get, Path),
+    ?assertMatch(#{data := [#{clientid := <<"my_client">>}]}, Clients),
+
+    {201, _} = request(post, MyClientSubscriptions, #{topic => <<"test/topic">>}),
+    {200, Subscriptions} = request(get, MyClientSubscriptions),
+    ?assertMatch([#{topic := <<"test/topic">>}], Subscriptions),
+    {204, _} = request(delete, MyClientSubscriptions ++ "/test%2Ftopic"),
+    {200, []} = request(get, MyClientSubscriptions),
+    {404, _} = request(delete, MyClientSubscriptions ++ "/test%2Ftopic"),
+
+    {204, _} = request(delete, MyClient),
+    {404, _} = request(delete, MyClient),
+    {404, _} = request(get, MyClient),
+    {404, _} = request(get, MyClientSubscriptions),
+    {404, _} = request(post, MyClientSubscriptions, #{topic => <<"foo">>}),
+    {404, _} = request(delete, MyClientSubscriptions ++ "/topic"),
+    {200, NoClients2} = request(get, Path),
+    ?assertMatch(#{data := []}, NoClients2),
+    emqx_gateway_test_utils:sn_client_disconnect(ClientSocket),
+    ok.
+
 t_authn_fuzzy_search(_) ->
     init_gw("stomp"),
     AuthConf = #{
diff --git a/apps/emqx_gateway/test/emqx_gateway_cli_SUITE.erl b/apps/emqx_gateway/test/emqx_gateway_cli_SUITE.erl
index 641528eda..fdaa55ab8 100644
--- a/apps/emqx_gateway/test/emqx_gateway_cli_SUITE.erl
+++ b/apps/emqx_gateway/test/emqx_gateway_cli_SUITE.erl
@@ -54,6 +54,8 @@ end).
     "}\n"
 ).
 
+-import(emqx_gateway_test_utils, [sn_client_connect/1, sn_client_disconnect/1]).
+
 %%--------------------------------------------------------------------
 %% Setup
 %%--------------------------------------------------------------------
@@ -303,17 +305,3 @@ acc_print(Acc) ->
     after 200 ->
         Acc
     end.
-
-sn_client_connect(ClientId) ->
-    {ok, Socket} = gen_udp:open(0, [binary]),
-    _ = emqx_sn_protocol_SUITE:send_connect_msg(Socket, ClientId),
-    ?assertEqual(
-        <<3, 16#05, 0>>,
-        emqx_sn_protocol_SUITE:receive_response(Socket)
-    ),
-    Socket.
-
-sn_client_disconnect(Socket) ->
-    _ = emqx_sn_protocol_SUITE:send_disconnect_msg(Socket, undefined),
-    gen_udp:close(Socket),
-    ok.
diff --git a/apps/emqx_gateway/test/emqx_gateway_test_utils.erl b/apps/emqx_gateway/test/emqx_gateway_test_utils.erl
index 2e8a3a583..950ae1bcf 100644
--- a/apps/emqx_gateway/test/emqx_gateway_test_utils.erl
+++ b/apps/emqx_gateway/test/emqx_gateway_test_utils.erl
@@ -19,6 +19,8 @@
 -compile(export_all).
 -compile(nowarn_export_all).
 
+-include_lib("eunit/include/eunit.hrl").
+
 assert_confs(Expected0, Effected) ->
     Expected = maybe_unconvert_listeners(Expected0),
     case do_assert_confs(root, Expected, Effected) of
@@ -181,3 +183,17 @@ url(Path, Qs) ->
 
 auth(Headers) ->
     [emqx_mgmt_api_test_util:auth_header_() | Headers].
+
+sn_client_connect(ClientId) ->
+    {ok, Socket} = gen_udp:open(0, [binary]),
+    _ = emqx_sn_protocol_SUITE:send_connect_msg(Socket, ClientId),
+    ?assertEqual(
+        <<3, 16#05, 0>>,
+        emqx_sn_protocol_SUITE:receive_response(Socket)
+    ),
+    Socket.
+
+sn_client_disconnect(Socket) ->
+    _ = emqx_sn_protocol_SUITE:send_disconnect_msg(Socket, undefined),
+    gen_udp:close(Socket),
+    ok.

From 3fd28f9e182ff34d96d85e5f01c6885ab06e562e Mon Sep 17 00:00:00 2001
From: Stefan Strigler <stefan.strigler@emqx.io>
Date: Fri, 7 Jul 2023 11:57:33 +0200
Subject: [PATCH 3/6] fix(emqx_management): return 404 for unknown listener id

---
 .../src/emqx_mgmt_api_listeners.erl           | 44 +++++++++----------
 .../test/emqx_mgmt_api_listeners_SUITE.erl    |  7 ++-
 2 files changed, 27 insertions(+), 24 deletions(-)

diff --git a/apps/emqx_management/src/emqx_mgmt_api_listeners.erl b/apps/emqx_management/src/emqx_mgmt_api_listeners.erl
index dd9013b16..8c20cbab8 100644
--- a/apps/emqx_management/src/emqx_mgmt_api_listeners.erl
+++ b/apps/emqx_management/src/emqx_mgmt_api_listeners.erl
@@ -45,14 +45,10 @@
     update/3
 ]).
 
--include_lib("emqx/include/emqx.hrl").
 -include_lib("hocon/include/hoconsc.hrl").
 
--define(NODE_LISTENER_NOT_FOUND, <<"Node name or listener id not found">>).
--define(NODE_NOT_FOUND_OR_DOWN, <<"Node not found or Down">>).
 -define(LISTENER_NOT_FOUND, <<"Listener id not found">>).
 -define(LISTENER_ID_INCONSISTENT, <<"Path and body's listener id not match">>).
--define(ADDR_PORT_INUSE, <<"Addr port in use">>).
 
 namespace() -> "listeners".
 
@@ -156,7 +152,7 @@ schema("/listeners/:id") ->
             parameters => [?R_REF(listener_id)],
             responses => #{
                 204 => <<"Listener deleted">>,
-                400 => error_codes(['BAD_REQUEST'])
+                404 => error_codes(['BAD_LISTENER_ID'])
             }
         }
     };
@@ -405,20 +401,8 @@ list_listeners(get, #{query_string := Query}) ->
 list_listeners(post, #{body := Body}) ->
     create_listener(Body).
 
-crud_listeners_by_id(get, #{bindings := #{id := Id0}}) ->
-    Listeners =
-        [
-            Conf#{
-                <<"id">> => Id,
-                <<"type">> => Type,
-                <<"bind">> := iolist_to_binary(
-                    emqx_listeners:format_bind(maps:get(<<"bind">>, Conf))
-                )
-            }
-         || {Id, Type, Conf} <- emqx_listeners:list_raw(),
-            Id =:= Id0
-        ],
-    case Listeners of
+crud_listeners_by_id(get, #{bindings := #{id := Id}}) ->
+    case find_listeners_by_id(Id) of
         [] -> {404, #{code => 'BAD_LISTENER_ID', message => ?LISTENER_NOT_FOUND}};
         [L] -> {200, L}
     end;
@@ -449,9 +433,12 @@ crud_listeners_by_id(post, #{body := Body}) ->
     create_listener(Body);
 crud_listeners_by_id(delete, #{bindings := #{id := Id}}) ->
     {ok, #{type := Type, name := Name}} = emqx_listeners:parse_listener_id(Id),
-    case ensure_remove(Type, Name) of
-        {ok, _} -> {204};
-        {error, Reason} -> {400, #{code => 'BAD_REQUEST', message => err_msg(Reason)}}
+    case find_listeners_by_id(Id) of
+        [_L] ->
+            {ok, _Res} = ensure_remove(Type, Name),
+            {204};
+        [] ->
+            {404, #{code => 'BAD_LISTENER_ID', message => ?LISTENER_NOT_FOUND}}
     end.
 
 parse_listener_conf(Conf0) ->
@@ -585,6 +572,19 @@ do_list_listeners() ->
         <<"listeners">> => Listeners
     }.
 
+find_listeners_by_id(Id) ->
+    [
+        Conf#{
+            <<"id">> => Id0,
+            <<"type">> => Type,
+            <<"bind">> := iolist_to_binary(
+                emqx_listeners:format_bind(maps:get(<<"bind">>, Conf))
+            )
+        }
+     || {Id0, Type, Conf} <- emqx_listeners:list_raw(),
+        Id0 =:= Id
+    ].
+
 wrap_rpc({badrpc, Reason}) ->
     {error, Reason};
 wrap_rpc(Res) ->
diff --git a/apps/emqx_management/test/emqx_mgmt_api_listeners_SUITE.erl b/apps/emqx_management/test/emqx_mgmt_api_listeners_SUITE.erl
index 862d81ab8..96ec8f2de 100644
--- a/apps/emqx_management/test/emqx_mgmt_api_listeners_SUITE.erl
+++ b/apps/emqx_management/test/emqx_mgmt_api_listeners_SUITE.erl
@@ -399,12 +399,15 @@ crud_listeners_by_id(ListenerId, NewListenerId, MinListenerId, BadId, Type, Port
     ?assertEqual([], delete(MinPath)),
     ?assertEqual({error, not_found}, is_running(NewListenerId)),
     ?assertMatch({error, {"HTTP/1.1", 404, _}}, request(get, NewPath, [], [])),
-    ?assertEqual([], delete(NewPath)),
+    ?assertMatch({error, {"HTTP/1.1", 404, _}}, request(delete, NewPath, [], [])),
     ok.
 
 t_delete_nonexistent_listener(Config) when is_list(Config) ->
     NonExist = emqx_mgmt_api_test_util:api_path(["listeners", "tcp:nonexistent"]),
-    ?assertEqual([], delete(NonExist)),
+    ?assertMatch(
+        {error, {_, 404, _}},
+        request(delete, NonExist, [], [])
+    ),
     ok.
 
 t_action_listeners(Config) when is_list(Config) ->

From 80e4ffff752918fa4db08091a7eb8b2bdf27b576 Mon Sep 17 00:00:00 2001
From: Stefan Strigler <stefan.strigler@emqx.io>
Date: Fri, 7 Jul 2023 13:17:52 +0200
Subject: [PATCH 4/6] fix(emqx_management): return 404 if plugin does not exist

---
 apps/emqx_management/src/emqx_mgmt_api_plugins.erl        | 3 +++
 apps/emqx_management/test/emqx_mgmt_api_plugins_SUITE.erl | 8 ++++++++
 2 files changed, 11 insertions(+)

diff --git a/apps/emqx_management/src/emqx_mgmt_api_plugins.erl b/apps/emqx_management/src/emqx_mgmt_api_plugins.erl
index f50e44771..3db0c42fb 100644
--- a/apps/emqx_management/src/emqx_mgmt_api_plugins.erl
+++ b/apps/emqx_management/src/emqx_mgmt_api_plugins.erl
@@ -132,6 +132,7 @@ schema("/plugins/:name") ->
             parameters => [hoconsc:ref(name)],
             responses => #{
                 204 => <<"Uninstall successfully">>,
+                400 => emqx_dashboard_swagger:error_codes(['PARAM_ERROR'], <<"Bad parameter">>),
                 404 => emqx_dashboard_swagger:error_codes(['NOT_FOUND'], <<"Plugin Not Found">>)
             }
         }
@@ -484,6 +485,8 @@ ensure_action(Name, restart) ->
 
 return(Code, ok) ->
     {Code};
+return(_, {error, #{error := "bad_info_file", return := {enoent, _} = Reason}}) ->
+    {404, #{code => 'NOT_FOUND', message => iolist_to_binary(io_lib:format("~p", [Reason]))}};
 return(_, {error, Reason}) ->
     {400, #{code => 'PARAM_ERROR', message => iolist_to_binary(io_lib:format("~p", [Reason]))}}.
 
diff --git a/apps/emqx_management/test/emqx_mgmt_api_plugins_SUITE.erl b/apps/emqx_management/test/emqx_mgmt_api_plugins_SUITE.erl
index 62fed8211..ba613abc4 100644
--- a/apps/emqx_management/test/emqx_mgmt_api_plugins_SUITE.erl
+++ b/apps/emqx_management/test/emqx_mgmt_api_plugins_SUITE.erl
@@ -133,6 +133,14 @@ t_bad_plugin(Config) ->
         )
     ).
 
+t_delete_non_existing(_Config) ->
+    Path = emqx_mgmt_api_test_util:api_path(["plugins", "non_exists"]),
+    ?assertMatch(
+        {error, {_, 404, _}},
+        emqx_mgmt_api_test_util:request_api(delete, Path)
+    ),
+    ok.
+
 list_plugins() ->
     Path = emqx_mgmt_api_test_util:api_path(["plugins"]),
     case emqx_mgmt_api_test_util:request_api(get, Path) of

From 1110b5d8f5768e314ffcb1570b7d8beb48028f60 Mon Sep 17 00:00:00 2001
From: Stefan Strigler <stefan.strigler@emqx.io>
Date: Fri, 7 Jul 2023 13:31:57 +0200
Subject: [PATCH 5/6] fix(emqx_retainer): return 404 in delete if topic not
 found

---
 apps/emqx_retainer/src/emqx_retainer.app.src        |  2 +-
 apps/emqx_retainer/src/emqx_retainer_api.erl        | 13 +++++++++++--
 apps/emqx_retainer/test/emqx_retainer_api_SUITE.erl |  1 +
 3 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/apps/emqx_retainer/src/emqx_retainer.app.src b/apps/emqx_retainer/src/emqx_retainer.app.src
index d13359509..f117fda05 100644
--- a/apps/emqx_retainer/src/emqx_retainer.app.src
+++ b/apps/emqx_retainer/src/emqx_retainer.app.src
@@ -2,7 +2,7 @@
 {application, emqx_retainer, [
     {description, "EMQX Retainer"},
     % strict semver, bump manually!
-    {vsn, "5.0.14"},
+    {vsn, "5.0.15"},
     {modules, []},
     {registered, [emqx_retainer_sup]},
     {applications, [kernel, stdlib, emqx, emqx_ctl]},
diff --git a/apps/emqx_retainer/src/emqx_retainer_api.erl b/apps/emqx_retainer/src/emqx_retainer_api.erl
index 7b1337140..3274f0e4c 100644
--- a/apps/emqx_retainer/src/emqx_retainer_api.erl
+++ b/apps/emqx_retainer/src/emqx_retainer_api.erl
@@ -102,6 +102,7 @@ schema(?PREFIX ++ "/message/:topic") ->
             parameters => parameters(),
             responses => #{
                 204 => <<>>,
+                404 => error_codes(['NOT_FOUND'], ?DESC(message_not_exist)),
                 400 => error_codes(
                     ['BAD_REQUEST'],
                     ?DESC(unsupported_backend)
@@ -187,8 +188,16 @@ with_topic(get, #{bindings := Bindings}) ->
     end;
 with_topic(delete, #{bindings := Bindings}) ->
     Topic = maps:get(topic, Bindings),
-    emqx_retainer_mnesia:delete_message(undefined, Topic),
-    {204}.
+    case emqx_retainer_mnesia:page_read(undefined, Topic, 1, 1) of
+        {ok, []} ->
+            {404, #{
+                code => <<"NOT_FOUND">>,
+                message => <<"Viewed message doesn't exist">>
+            }};
+        {ok, _} ->
+            emqx_retainer_mnesia:delete_message(undefined, Topic),
+            {204}
+    end.
 
 format_message(#message{
     id = ID,
diff --git a/apps/emqx_retainer/test/emqx_retainer_api_SUITE.erl b/apps/emqx_retainer/test/emqx_retainer_api_SUITE.erl
index 61eee0510..d00ade556 100644
--- a/apps/emqx_retainer/test/emqx_retainer_api_SUITE.erl
+++ b/apps/emqx_retainer/test/emqx_retainer_api_SUITE.erl
@@ -218,6 +218,7 @@ t_lookup_and_delete(_) ->
     {ok, []} = request_api(delete, API),
 
     {error, {"HTTP/1.1", 404, "Not Found"}} = request_api(get, API),
+    {error, {"HTTP/1.1", 404, "Not Found"}} = request_api(delete, API),
 
     ok = emqtt:disconnect(C1).
 

From da052e0a5e1720c63930232701f47477ac5f1e09 Mon Sep 17 00:00:00 2001
From: Stefan Strigler <stefan.strigler@emqx.io>
Date: Fri, 7 Jul 2023 16:38:27 +0200
Subject: [PATCH 6/6] chore: add changelog

---
 changes/ce/fix-11211.en.md | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 changes/ce/fix-11211.en.md

diff --git a/changes/ce/fix-11211.en.md b/changes/ce/fix-11211.en.md
new file mode 100644
index 000000000..0b69fefca
--- /dev/null
+++ b/changes/ce/fix-11211.en.md
@@ -0,0 +1 @@
+Consistently return `404` for `DELETE` operations on non-existent resources.