From c7a90d73b25741be9b616ca325277ba05ccc78fb Mon Sep 17 00:00:00 2001
From: "Zaiming (Stone) Shi" <zmstone@gmail.com>
Date: Wed, 19 Oct 2022 17:09:37 +0200
Subject: [PATCH 01/13] fix(shared): do not redispatch shared messages for
 certain shutdown

For takeover, there should be no message re-dispatch because
the messages will be retried by the new session.

For kick, messages should not be re-dispatched for security reason.
i.e. if admin has identified that there are malicious messages
stored in persisted sessions, killing the session should not
cause messages to be re-dispatched
---
 apps/emqx/src/emqx_session.erl           |  10 +-
 apps/emqx/test/emqx_shared_sub_SUITE.erl | 135 ++++++++++++++++++++++-
 2 files changed, 137 insertions(+), 8 deletions(-)

diff --git a/apps/emqx/src/emqx_session.erl b/apps/emqx/src/emqx_session.erl
index b285d0a88..51e57462b 100644
--- a/apps/emqx/src/emqx_session.erl
+++ b/apps/emqx/src/emqx_session.erl
@@ -802,8 +802,7 @@ replay(ClientInfo, Session = #session{inflight = Inflight}) ->
 -spec terminate(emqx_types:clientinfo(), Reason :: term(), session()) -> ok.
 terminate(ClientInfo, Reason, Session) ->
     run_terminate_hooks(ClientInfo, Reason, Session),
-    Reason =/= takenover andalso
-        redispatch_shared_messages(Session),
+    maybe_redispatch_shared_messages(Reason, Session),
     ok.
 
 run_terminate_hooks(ClientInfo, discarded, Session) ->
@@ -813,6 +812,13 @@ run_terminate_hooks(ClientInfo, takenover, Session) ->
 run_terminate_hooks(ClientInfo, Reason, Session) ->
     run_hook('session.terminated', [ClientInfo, Reason, info(Session)]).
 
+maybe_redispatch_shared_messages(takenover, _Session) ->
+    ok;
+maybe_redispatch_shared_messages(kicked, _Session) ->
+    ok;
+maybe_redispatch_shared_messages(_Reason, Session) ->
+    redispatch_shared_messages(Session).
+
 redispatch_shared_messages(#session{inflight = Inflight, mqueue = Q}) ->
     AllInflights = emqx_inflight:to_list(fun sort_fun/2, Inflight),
     F = fun
diff --git a/apps/emqx/test/emqx_shared_sub_SUITE.erl b/apps/emqx/test/emqx_shared_sub_SUITE.erl
index 291286aa2..dab4c698a 100644
--- a/apps/emqx/test/emqx_shared_sub_SUITE.erl
+++ b/apps/emqx/test/emqx_shared_sub_SUITE.erl
@@ -750,11 +750,16 @@ t_dispatch_qos2(Config) when is_list(Config) ->
     ?assertMatch([{_, _, {ok, 1}}], emqx:publish(Message3)),
     ?assertMatch([{_, _, {ok, 1}}], emqx:publish(Message4)),
 
+    %% assert client 2 receives two messages, they are eiter 1,3 or 2,4 depending
+    %% on if it's picked as the first one for round_robin
     MsgRec1 = ?WAIT(2000, {publish, #{client_pid := ConnPid2, payload := P1}}, P1),
     MsgRec2 = ?WAIT(2000, {publish, #{client_pid := ConnPid2, payload := P2}}, P2),
-    %% assert hello2 > hello1 or hello4 > hello3
-    ?assert(MsgRec2 > MsgRec1),
-
+    case MsgRec2 of
+        <<"hello3">> ->
+            ?assertEqual(<<"hello1">>, MsgRec1);
+        <<"hello4">> ->
+            ?assertEqual(<<"hello2">>, MsgRec1)
+    end,
     sys:resume(ConnPid1),
     %% emqtt subscriber automatically sends PUBREC, but since auto_ack is set to false
     %% so it will never send PUBCOMP, hence EMQX should not attempt to send
@@ -767,8 +772,14 @@ t_dispatch_qos2(Config) when is_list(Config) ->
     kill_process(ConnPid1),
     %% client 2 should receive the message
     MsgRec4 = ?WAIT(2000, {publish, #{client_pid := ConnPid2, payload := P4}}, P4),
-    %% assert hello2 > hello1 or hello4 > hello3
-    ?assert(MsgRec4 > MsgRec3),
+    case MsgRec2 of
+        <<"hello3">> ->
+            ?assertEqual(<<"hello2">>, MsgRec3),
+            ?assertEqual(<<"hello4">>, MsgRec4);
+        <<"hello4">> ->
+            ?assertEqual(<<"hello1">>, MsgRec3),
+            ?assertEqual(<<"hello3">>, MsgRec4)
+    end,
     emqtt:stop(ConnPid2),
     ok.
 
@@ -817,17 +828,129 @@ t_dispatch_qos0(Config) when is_list(Config) ->
     emqtt:stop(ConnPid2),
     ok.
 
+t_session_takeover({init, Config}) when is_list(Config) ->
+    Config;
+t_session_takeover({'end', Config}) when is_list(Config) ->
+    ok;
+t_session_takeover(Config) when is_list(Config) ->
+    Topic = <<"t1/a">>,
+    ClientId = iolist_to_binary("c" ++ integer_to_list(erlang:system_time())),
+    Opts = [
+        {clientid, ClientId},
+        {auto_ack, true},
+        {proto_ver, v5},
+        {clean_start, false},
+        {properties, #{'Session-Expiry-Interval' => 60}}
+    ],
+    {ok, ConnPid1} = emqtt:start_link(Opts),
+    %% with the same client ID, start another client
+    {ok, ConnPid2} = emqtt:start_link(Opts),
+    {ok, _} = emqtt:connect(ConnPid1),
+    emqtt:subscribe(ConnPid1, {<<"$share/t1/", Topic/binary>>, _QoS = 1}),
+    Message1 = emqx_message:make(<<"dummypub">>, 2, Topic, <<"hello1">>),
+    Message2 = emqx_message:make(<<"dummypub">>, 2, Topic, <<"hello2">>),
+    Message3 = emqx_message:make(<<"dummypub">>, 2, Topic, <<"hello3">>),
+    Message4 = emqx_message:make(<<"dummypub">>, 2, Topic, <<"hello4">>),
+    %% Make sure client1 is functioning
+    ?assertMatch([_], emqx:publish(Message1)),
+    {true, _} = last_message(<<"hello1">>, [ConnPid1]),
+    %% Kill client1
+    emqtt:stop(ConnPid1),
+    %% publish another message (should end up in client1's session)
+    ?assertMatch([_], emqx:publish(Message2)),
+    %% connect client2 (with the same clientid)
+
+    %% should trigger session take over
+    {ok, _} = emqtt:connect(ConnPid2),
+    ?assertMatch([_], emqx:publish(Message3)),
+    ?assertMatch([_], emqx:publish(Message4)),
+    {true, _} = last_message(<<"hello2">>, [ConnPid1]),
+    {true, _} = last_message(<<"hello3">>, [ConnPid1]),
+    {true, _} = last_message(<<"hello4">>, [ConnPid1]),
+    ?assertEqual([], collect_msgs(timer:seconds(2))),
+    emqtt:stop(ConnPid2),
+    ok.
+
+t_session_kicked({init, Config}) when is_list(Config) ->
+    emqx_config:put_zone_conf(default, [mqtt, max_inflight], 1),
+    Config;
+t_session_kicked({'end', Config}) when is_list(Config) ->
+    emqx_config:put_zone_conf(default, [mqtt, max_inflight], 0);
+t_session_kicked(Config) when is_list(Config) ->
+    ok = ensure_config(round_robin, _AckEnabled = false),
+    Topic = <<"foo/bar/1">>,
+    ClientId1 = <<"ClientId1">>,
+    ClientId2 = <<"ClientId2">>,
+
+    {ok, ConnPid1} = emqtt:start_link([{clientid, ClientId1}, {auto_ack, false}]),
+    {ok, ConnPid2} = emqtt:start_link([{clientid, ClientId2}, {auto_ack, true}]),
+    {ok, _} = emqtt:connect(ConnPid1),
+    {ok, _} = emqtt:connect(ConnPid2),
+
+    emqtt:subscribe(ConnPid1, {<<"$share/group/foo/bar/#">>, 2}),
+    emqtt:subscribe(ConnPid2, {<<"$share/group/foo/bar/#">>, 2}),
+
+    Message1 = emqx_message:make(ClientId1, 2, Topic, <<"hello1">>),
+    Message2 = emqx_message:make(ClientId1, 2, Topic, <<"hello2">>),
+    Message3 = emqx_message:make(ClientId1, 2, Topic, <<"hello3">>),
+    Message4 = emqx_message:make(ClientId1, 2, Topic, <<"hello4">>),
+    ct:sleep(100),
+
+    ok = sys:suspend(ConnPid1),
+
+    %% One message is inflight
+    ?assertMatch([{_, _, {ok, 1}}], emqx:publish(Message1)),
+    ?assertMatch([{_, _, {ok, 1}}], emqx:publish(Message2)),
+    ?assertMatch([{_, _, {ok, 1}}], emqx:publish(Message3)),
+    ?assertMatch([{_, _, {ok, 1}}], emqx:publish(Message4)),
+
+    %% assert client 2 receives two messages, they are eiter 1,3 or 2,4 depending
+    %% on if it's picked as the first one for round_robin
+    MsgRec1 = ?WAIT(2000, {publish, #{client_pid := ConnPid2, payload := P1}}, P1),
+    MsgRec2 = ?WAIT(2000, {publish, #{client_pid := ConnPid2, payload := P2}}, P2),
+    case MsgRec2 of
+        <<"hello3">> ->
+            ?assertEqual(<<"hello1">>, MsgRec1);
+        <<"hello4">> ->
+            ?assertEqual(<<"hello2">>, MsgRec1)
+    end,
+    sys:resume(ConnPid1),
+    %% emqtt subscriber automatically sends PUBREC, but since auto_ack is set to false
+    %% so it will never send PUBCOMP, hence EMQX should not attempt to send
+    %% the 4th message yet since max_inflight is 1.
+    MsgRec3 = ?WAIT(2000, {publish, #{client_pid := ConnPid1, payload := P3}}, P3),
+    case MsgRec2 of
+        <<"hello3">> ->
+            ?assertEqual(<<"hello2">>, MsgRec3);
+        <<"hello4">> ->
+            ?assertEqual(<<"hello1">>, MsgRec3)
+    end,
+    %% no message expected
+    ?assertEqual([], collect_msgs(0)),
+    %% now kick client 1
+    kill_process(ConnPid1, fun(_Pid) -> emqx_cm:kick_session(ClientId1) end),
+    %% client 2 should NOT receive the message
+    ?assertEqual([], collect_msgs(1000)),
+    emqtt:stop(ConnPid2),
+    ?assertEqual([], collect_msgs(0)),
+    ok.
+
 %%--------------------------------------------------------------------
 %% help functions
 %%--------------------------------------------------------------------
 
 kill_process(Pid) ->
+    kill_process(Pid, fun(_) -> erlang:exit(Pid, kill) end).
+
+kill_process(Pid, WithFun) ->
     _ = unlink(Pid),
     _ = monitor(process, Pid),
-    erlang:exit(Pid, kill),
+    _ = WithFun(Pid),
     receive
         {'DOWN', _, process, Pid, _} ->
             ok
+    after 10_000 ->
+        error(timeout)
     end.
 
 collect_msgs(Timeout) ->

From fa020d036f702a0b702dee8b6ba45a49b8ed62b1 Mon Sep 17 00:00:00 2001
From: JianBo He <heeejianbo@gmail.com>
Date: Thu, 20 Oct 2022 15:30:52 +0800
Subject: [PATCH 02/13] chore(docs): translate Max Awaiting PUBREL confs

---
 apps/emqx/i18n/emqx_schema_i18n.conf | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/apps/emqx/i18n/emqx_schema_i18n.conf b/apps/emqx/i18n/emqx_schema_i18n.conf
index 17e59a4dd..ae9da4579 100644
--- a/apps/emqx/i18n/emqx_schema_i18n.conf
+++ b/apps/emqx/i18n/emqx_schema_i18n.conf
@@ -869,23 +869,25 @@ When set to true, invalid utf8 strings in for example client ID, topic name, etc
 
     mqtt_max_awaiting_rel {
         desc {
-            en: """Maximum QoS 2 packets (Client -> Broker) awaiting PUBREL."""
-            zh: """PUBREL (Client -> Broker) 最大等待队列长度。"""
+            en: """EMQX creates a wait queue in the client's session to accept QoS 2 messages from the client until this QoS 2 message transmission is complete or is discarded due to timeout.</br>
+After this queue is full, the processing of QoS 2 messages will be stopped."""
+            zh: """EMQX 会在客户端的会话中创建一个等待队列来接受客户端的 QoS 2 消息，直到这条 QoS 2 消息传输完成或由于超时被丢弃。</br>
+该队列满后会停止处理 QoS 2 消息。"""
         }
         label: {
             en: """Max Awaiting PUBREL"""
-            zh: """Max Awaiting PUBREL"""
+            zh: """PUBREL 等待队列长度"""
         }
     }
 
     mqtt_await_rel_timeout {
         desc {
-            en: """The QoS 2 messages (Client -> Broker) will be dropped if awaiting PUBREL timeout."""
-            zh: """PUBREL (Client -> Broker) 最大等待时间，超时则会被丢弃。"""
+            en: """The QoS 2 messages (Client -> Broker) handle flow will be ignored if awaiting PUBREL timeout. This QoS 2 message can be published successfully."""
+            zh: """如果等待 PUBREL 超时，QoS 2消息（Client -> Broker）处理流程将被忽略。这条 QoS 2 仍然会成功发布。"""
         }
         label: {
             en: """Max Awaiting PUBREL TIMEOUT"""
-            zh: """Max Awaiting PUBREL TIMEOUT"""
+            zh: """PUBREL 最大等待时间"""
         }
     }
 

From b3ffe89f3521f93207de36765a089e0eda264f39 Mon Sep 17 00:00:00 2001
From: "Zaiming (Stone) Shi" <zmstone@gmail.com>
Date: Wed, 19 Oct 2022 18:16:38 +0200
Subject: [PATCH 03/13] test: assert message receive pid is in the expected
 pids list

---
 apps/emqx/test/emqx_shared_sub_SUITE.erl | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/apps/emqx/test/emqx_shared_sub_SUITE.erl b/apps/emqx/test/emqx_shared_sub_SUITE.erl
index dab4c698a..bc519117b 100644
--- a/apps/emqx/test/emqx_shared_sub_SUITE.erl
+++ b/apps/emqx/test/emqx_shared_sub_SUITE.erl
@@ -465,7 +465,7 @@ last_message(ExpectedPayload, Pids) ->
 last_message(ExpectedPayload, Pids, Timeout) ->
     receive
         {publish, #{client_pid := Pid, payload := ExpectedPayload}} ->
-            ct:pal("~p ====== ~p", [Pids, Pid]),
+            ?assert(lists:member(Pid, Pids)),
             {true, Pid}
     after Timeout ->
         ct:pal("not yet"),
@@ -864,9 +864,9 @@ t_session_takeover(Config) when is_list(Config) ->
     {ok, _} = emqtt:connect(ConnPid2),
     ?assertMatch([_], emqx:publish(Message3)),
     ?assertMatch([_], emqx:publish(Message4)),
-    {true, _} = last_message(<<"hello2">>, [ConnPid1]),
-    {true, _} = last_message(<<"hello3">>, [ConnPid1]),
-    {true, _} = last_message(<<"hello4">>, [ConnPid1]),
+    {true, _} = last_message(<<"hello2">>, [ConnPid2]),
+    {true, _} = last_message(<<"hello3">>, [ConnPid2]),
+    {true, _} = last_message(<<"hello4">>, [ConnPid2]),
     ?assertEqual([], collect_msgs(timer:seconds(2))),
     emqtt:stop(ConnPid2),
     ok.

From 67dd733e8d3ede357d109d0068725d1eeeeb451f Mon Sep 17 00:00:00 2001
From: "Zaiming (Stone) Shi" <zmstone@gmail.com>
Date: Thu, 20 Oct 2022 18:34:35 +0200
Subject: [PATCH 04/13] chore: bump to gun 1.3.9

1.3.7 had a bug which caused ssl_passive message unhandled
---
 mix.exs      | 2 +-
 rebar.config | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/mix.exs b/mix.exs
index a2863f137..43024c116 100644
--- a/mix.exs
+++ b/mix.exs
@@ -71,7 +71,7 @@ defmodule EMQXUmbrella.MixProject do
       {:esasl, github: "emqx/esasl", tag: "0.2.0"},
       {:jose, github: "potatosalad/erlang-jose", tag: "1.11.2"},
       # in conflict by ehttpc and emqtt
-      {:gun, github: "emqx/gun", tag: "1.3.7", override: true},
+      {:gun, github: "emqx/gun", tag: "1.3.9", override: true},
       # in conflict by emqx_connectior and system_monitor
       {:epgsql, github: "emqx/epgsql", tag: "4.7-emqx.2", override: true},
       # in conflict by mongodb and eredis_cluster
diff --git a/rebar.config b/rebar.config
index 9be69d963..f415b5901 100644
--- a/rebar.config
+++ b/rebar.config
@@ -48,7 +48,7 @@
     , {redbug, "2.0.7"}
     , {gpb, "4.19.5"} %% gpb only used to build, but not for release, pin it here to avoid fetching a wrong version due to rebar plugins scattered in all the deps
     , {typerefl, {git, "https://github.com/ieQu1/typerefl", {tag, "0.9.1"}}}
-    , {gun, {git, "https://github.com/emqx/gun", {tag, "1.3.7"}}}
+    , {gun, {git, "https://github.com/emqx/gun", {tag, "1.3.9"}}}
     , {ehttpc, {git, "https://github.com/emqx/ehttpc", {tag, "0.3.0"}}}
     , {gproc, {git, "https://github.com/uwiger/gproc", {tag, "0.8.0"}}}
     , {jiffy, {git, "https://github.com/emqx/jiffy", {tag, "1.0.5"}}}

From 05793ef1e516400694c12cd96a8a826324ab235d Mon Sep 17 00:00:00 2001
From: "Zaiming (Stone) Shi" <zmstone@gmail.com>
Date: Thu, 20 Oct 2022 19:13:09 +0200
Subject: [PATCH 05/13] chore: upgrade to dashboard v1.1.0

---
 Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index 74204afac..eeabaed33 100644
--- a/Makefile
+++ b/Makefile
@@ -6,7 +6,7 @@ export EMQX_DEFAULT_BUILDER = ghcr.io/emqx/emqx-builder/5.0-17:1.13.4-24.2.1-1-d
 export EMQX_DEFAULT_RUNNER = debian:11-slim
 export OTP_VSN ?= $(shell $(CURDIR)/scripts/get-otp-vsn.sh)
 export ELIXIR_VSN ?= $(shell $(CURDIR)/scripts/get-elixir-vsn.sh)
-export EMQX_DASHBOARD_VERSION ?= v1.0.9
+export EMQX_DASHBOARD_VERSION ?= v1.1.0
 export EMQX_EE_DASHBOARD_VERSION ?= e1.0.0
 export EMQX_REL_FORM ?= tgz
 export QUICER_DOWNLOAD_FROM_RELEASE = 1

From d1332b72e7f7e4075bfb7aa575449560baa9a146 Mon Sep 17 00:00:00 2001
From: "Zaiming (Stone) Shi" <zmstone@gmail.com>
Date: Tue, 18 Oct 2022 21:33:29 +0200
Subject: [PATCH 06/13] feat(api/publish): return detailed publish results

Prior to this change, the publish API returns 200 in most of
the cases.
This change provides more insights to the publish result.

For single message publish endpoint (`publish/`):

HTTP error codes are:

200: Everything is OK
202: No subscriber for the topic
400: When mesage is invalid message.
     e.g. bad topic name or QoS out of range.
503: Failed to dispatch the message. e.g. during EMQX restart.

The response body is a JSON object with two fields
`message_id`, and `publish_result`.
The `message_id` is a globally unique ID for tracing.
`publish_result` is `"OK"` when the message is delivered
to at least one subscriber.
Otherwise `"no_subscriber"`.
`publish_result` may also be some other informative
message to hint the failure result, the content of which
may change in the future.

For `publish/bulk` endpoint:

200: When all message in the bulk are published OK
202: If at least one message in the bulk had `"no_subscriber"` result
400: When mesage is invalid message. e.g. bad topic name or
     QoS out of range.
503: When there is at least one message failed at dispatch.

The reply body is a list of JSON objects having the same layout
as for hte `publish` endpoint.
---
 apps/emqx/src/emqx_message.erl                |  15 +-
 .../i18n/emqx_mgmt_api_publish_i18n.conf      | 127 +++++++++
 .../src/emqx_mgmt_api_publish.erl             | 241 ++++++++++++++---
 .../test/emqx_mgmt_api_publish_SUITE.erl      | 246 +++++++++++++++++-
 .../test/emqx_mgmt_api_test_util.erl          |  18 +-
 5 files changed, 604 insertions(+), 43 deletions(-)
 create mode 100644 apps/emqx_management/i18n/emqx_mgmt_api_publish_i18n.conf

diff --git a/apps/emqx/src/emqx_message.erl b/apps/emqx/src/emqx_message.erl
index ae74a614b..03f7ca6a2 100644
--- a/apps/emqx/src/emqx_message.erl
+++ b/apps/emqx/src/emqx_message.erl
@@ -74,7 +74,8 @@
     to_map/1,
     to_log_map/1,
     to_list/1,
-    from_map/1
+    from_map/1,
+    estimate_size/1
 ]).
 
 -export_type([message_map/0]).
@@ -175,6 +176,18 @@ make(MsgId, From, QoS, Topic, Payload, Flags, Headers) when
         timestamp = Now
     }.
 
+%% optimistic esitmation of a message size after serialization
+%% not including MQTT v5 message headers/user properties etc.
+-spec estimate_size(emqx_types:message()) -> non_neg_integer().
+estimate_size(#message{topic = Topic, payload = Payload}) ->
+    FixedHeaderSize = 1,
+    VarLenSize = 4,
+    TopicSize = iolist_size(Topic),
+    PayloadSize = iolist_size(Payload),
+    PacketIdSize = 2,
+    TopicLengthSize = 2,
+    FixedHeaderSize + VarLenSize + TopicLengthSize + TopicSize + PacketIdSize + PayloadSize.
+
 -spec id(emqx_types:message()) -> maybe(binary()).
 id(#message{id = Id}) -> Id.
 
diff --git a/apps/emqx_management/i18n/emqx_mgmt_api_publish_i18n.conf b/apps/emqx_management/i18n/emqx_mgmt_api_publish_i18n.conf
new file mode 100644
index 000000000..2a7c9def8
--- /dev/null
+++ b/apps/emqx_management/i18n/emqx_mgmt_api_publish_i18n.conf
@@ -0,0 +1,127 @@
+
+emqx_mgmt_api_publish {
+    publish_api {
+        desc {
+            en: """
+Publish one message.<br/>
+Possible HTTP status response codes are:<br/>
+<code>200</code>: The message is delivered to at least one subscriber;<br/>
+<code>202</code>: No matched subscribers;<br/>
+<code>400</code>: Message is invalid. for example bad topic name, or QoS is out of range;<br/>
+<code>503</code>: Failed to deliver the message to subscriber(s);<br/>
+"""
+            zh: """
+发布一个消息。<br/>
+可能的 HTTP 状态码如下：<br/>
+200: 消息被成功发送到至少一个订阅。<br/>
+202: 没有匹配到任何订阅。<br/>
+400: 消息编码错误，如非法主题，或 QoS 超出范围等。<br/>
+503: 服务重启等过程中导致转发失败。<br/><br/>
+"""
+        }
+    }
+    publish_bulk_api {
+        desc {
+            en: """
+Publish a batch of messages.<br/>
+Possible HTTP response status code are:<br/>
+200: All messages are delivered to at least one subscriber;<br/>
+202: At least one message was not delivered to any subscriber;<br/>
+400: At least one message is invalid. For example bad topic name, or QoS is out of range;<br/>
+503: Failed to deliver at least one of the messages;<br/>
+
+In case there is at lest one invalid message in the batch, the HTTP response body
+is the same as for <code>/publish</code> API.<br/>
+Otherwise the HTTP response body is an array of JSON objects indicating the publish
+result of each individual message in the batch.
+"""
+            zh: """
+批量发布一组消息。<br/>
+可能的 HTTP 状态码如下：<br/>
+200: 所有的消息都被成功发送到至少一个订阅。<br/>
+202: 至少有一个消息没有匹配到任何订阅。<br/>
+400: 至少有一个消息编码错误，如非法主题，或 QoS 超出范围等。<br/>
+503: 至少有一个小因为服务重启的原因导致转发失败。<br/>
+
+请求的 Body 或者 Body 中包含的某个消息无法通过 API 规范的类型检查时，HTTP 响应的消息与发布单个消息的 API
+ <code>/publish</code> 是一样的。
+如果所有的消息都是合法的，那么 HTTP 返回的内容是一个 JSON 数组，每个元素代表了该消息转发的状态。
+
+"""
+        }
+    }
+
+    topic_name {
+        desc {
+            en: "Topic Name"
+            zh: "主题名称"
+        }
+    }
+    qos {
+        desc {
+            en: "MQTT message QoS"
+            zh: "MQTT 消息的 QoS"
+        }
+    }
+    clientid {
+        desc {
+            en: "Each message can be published as if it is done on behalf of an MQTT client whos ID can be specified in this field."
+            zh: "每个消息都可以带上一个 MQTT 客户端 ID，用于模拟 MQTT 客户端的发布行为。"
+        }
+    }
+    payload {
+        desc {
+            en: "The MQTT message payload."
+            zh: "MQTT 消息体。"
+        }
+    }
+    retain {
+        desc {
+            en: "A boolean field to indicate if this message should be retained."
+            zh: "布尔型字段，用于表示该消息是否保留消息。"
+        }
+    }
+    payload_encoding {
+        desc {
+            en: "MQTT Payload Encoding, <code>base64</code> or <code>plain</code>. When set to <code>base64</code>, the message is decoded before it is published."
+            zh: "MQTT 消息体的编码方式，可以是 <code>base64</code> 或 <code>plain</code>。当设置为 <code>base64</code> 时，消息在发布前会先被解码。"
+        }
+    }
+    message_id {
+        desc {
+            en: "A globally unique message ID for correlation/tracing."
+            zh: "全局唯一的一个消息 ID，方便用于关联和追踪。"
+        }
+    }
+    reason_code {
+        desc {
+            en: """
+The MQTT reason code, as the same ones used in PUBACK packet.<br/>
+Currently supported codes are:<br/>
+
+16(0x10): No matching subscribers;<br/>
+131(0x81): Error happened when dispatching the message. e.g. during EMQX restart;<br/>
+144(0x90): Topic name invalid;<br/>
+151(0x97): Publish rate limited, or message size exceeded limit. The global size limit can be configured with <code>mqtt.max_packet_size</code><br/>
+NOTE: The message size is estimated with the received topic and payload size, meaning the actual size of serialized bytes (when sent to MQTT subscriber)
+might be slightly over the limit.
+"""
+            zh: """
+MQTT 消息发布的错误码，这些错误码也是 MQTT 规范中 PUBACK 消息可能携带的错误码。<br/>
+当前支持如下错误码：<br/>
+
+16(0x10)：没能匹配到任何订阅；<br/>
+131(0x81)：消息转发时发生错误，例如 EMQX 服务重启；<br/>
+144(0x90)：主题名称非法；<br/>
+151(0x97)：受到了速率限制，或者消息尺寸过大。全局消息大小限制可以通过配置项 <code>mqtt.max_packet_size</code> 来进行修改。<br/>
+注意：消息尺寸的是通过主题和消息体的字节数进行估算的。具体发布时所占用的字节数可能会稍大于这个估算的值。
+"""
+        }
+    }
+    error_message {
+        desc {
+            en: "Describes the failure reason in detail."
+            zh: "失败的详细原因。"
+        }
+    }
+}
diff --git a/apps/emqx_management/src/emqx_mgmt_api_publish.erl b/apps/emqx_management/src/emqx_mgmt_api_publish.erl
index 0e05a3875..1678c56e0 100644
--- a/apps/emqx_management/src/emqx_mgmt_api_publish.erl
+++ b/apps/emqx_management/src/emqx_mgmt_api_publish.erl
@@ -16,7 +16,15 @@
 -module(emqx_mgmt_api_publish).
 
 -include_lib("emqx/include/emqx.hrl").
+-include_lib("emqx/include/emqx_mqtt.hrl").
 -include_lib("typerefl/include/types.hrl").
+-include_lib("emqx/include/logger.hrl").
+-include_lib("hocon/include/hoconsc.hrl").
+
+-define(ALL_IS_WELL, 200).
+-define(PARTIALLY_OK, 202).
+-define(BAD_REQUEST, 400).
+-define(DISPATCH_ERROR, 503).
 
 -behaviour(minirest_api).
 
@@ -42,11 +50,14 @@ schema("/publish") ->
     #{
         'operationId' => publish,
         post => #{
-            description => <<"Publish Message">>,
+            description => ?DESC(publish_api),
             tags => [<<"Publish">>],
             'requestBody' => hoconsc:mk(hoconsc:ref(?MODULE, publish_message)),
             responses => #{
-                200 => hoconsc:mk(hoconsc:ref(?MODULE, publish_message_info))
+                ?ALL_IS_WELL => hoconsc:mk(hoconsc:ref(?MODULE, publish_ok)),
+                ?PARTIALLY_OK => hoconsc:mk(hoconsc:ref(?MODULE, publish_error)),
+                ?BAD_REQUEST => bad_request_schema(),
+                ?DISPATCH_ERROR => hoconsc:mk(hoconsc:ref(?MODULE, publish_error))
             }
         }
     };
@@ -54,44 +65,58 @@ schema("/publish/bulk") ->
     #{
         'operationId' => publish_batch,
         post => #{
-            description => <<"Publish Messages">>,
+            description => ?DESC(publish_bulk_api),
             tags => [<<"Publish">>],
             'requestBody' => hoconsc:mk(hoconsc:array(hoconsc:ref(?MODULE, publish_message)), #{}),
             responses => #{
-                200 => hoconsc:mk(hoconsc:array(hoconsc:ref(?MODULE, publish_message_info)), #{})
+                ?ALL_IS_WELL => hoconsc:mk(hoconsc:array(hoconsc:ref(?MODULE, publish_ok)), #{}),
+                ?PARTIALLY_OK => hoconsc:mk(
+                    hoconsc:array(hoconsc:ref(?MODULE, publish_error)), #{}
+                ),
+                ?BAD_REQUEST => bad_request_schema(),
+                ?DISPATCH_ERROR => hoconsc:mk(
+                    hoconsc:array(hoconsc:ref(?MODULE, publish_error)), #{}
+                )
             }
         }
     }.
 
+bad_request_schema() ->
+    Union = hoconsc:union([
+        hoconsc:ref(?MODULE, bad_request),
+        hoconsc:array(hoconsc:ref(?MODULE, publish_error))
+    ]),
+    hoconsc:mk(Union, #{}).
+
 fields(message) ->
     [
         {topic,
             hoconsc:mk(binary(), #{
-                desc => <<"Topic Name">>,
+                desc => ?DESC(topic_name),
                 required => true,
                 example => <<"api/example/topic">>
             })},
         {qos,
             hoconsc:mk(emqx_schema:qos(), #{
-                desc => <<"MQTT QoS">>,
+                desc => ?DESC(qos),
                 required => false,
                 default => 0
             })},
         {clientid,
             hoconsc:mk(binary(), #{
-                desc => <<"From client ID">>,
+                desc => ?DESC(clientid),
                 required => false,
                 example => <<"api_example_client">>
             })},
         {payload,
             hoconsc:mk(binary(), #{
-                desc => <<"MQTT Payload">>,
+                desc => ?DESC(payload),
                 required => true,
                 example => <<"hello emqx api">>
             })},
         {retain,
             hoconsc:mk(boolean(), #{
-                desc => <<"MQTT Retain Message">>,
+                desc => ?DESC(retain),
                 required => false,
                 default => false
             })}
@@ -100,53 +125,196 @@ fields(publish_message) ->
     [
         {payload_encoding,
             hoconsc:mk(hoconsc:enum([plain, base64]), #{
-                desc => <<"MQTT Payload Encoding, base64 or plain">>,
+                desc => ?DESC(payload_encoding),
                 required => false,
                 default => plain
             })}
     ] ++ fields(message);
-fields(publish_message_info) ->
+fields(publish_ok) ->
     [
         {id,
             hoconsc:mk(binary(), #{
-                desc => <<"A globally unique message ID">>
+                desc => ?DESC(message_id)
+            })}
+    ];
+fields(publish_error) ->
+    [
+        {reason_code,
+            hoconsc:mk(integer(), #{
+                desc => ?DESC(reason_code),
+                example => 16
+            })},
+        {message,
+            hoconsc:mk(binary(), #{
+                desc => ?DESC(error_message),
+                example => <<"no_matching_subscribers">>
+            })}
+    ];
+fields(bad_request) ->
+    [
+        {code,
+            hoconsc:mk(string(), #{
+                desc => <<"BAD_REQUEST">>
+            })},
+        {message,
+            hoconsc:mk(binary(), #{
+                desc => ?DESC(error_message)
             })}
     ].
 
 publish(post, #{body := Body}) ->
     case message(Body) of
         {ok, Message} ->
-            _ = emqx_mgmt:publish(Message),
-            {200, format_message_response(Message)};
-        {error, R} ->
-            {400, 'BAD_REQUEST', to_binary(R)}
+            Res = emqx_mgmt:publish(Message),
+            publish_result_to_http_reply(Message, Res);
+        {error, Reason} ->
+            {?BAD_REQUEST, make_bad_req_reply(Reason)}
     end.
 
 publish_batch(post, #{body := Body}) ->
     case messages(Body) of
         {ok, Messages} ->
-            _ = [emqx_mgmt:publish(Message) || Message <- Messages],
-            {200, format_message_response(Messages)};
-        {error, R} ->
-            {400, 'BAD_REQUEST', to_binary(R)}
+            ResList = lists:map(
+                fun(Message) ->
+                    Res = emqx_mgmt:publish(Message),
+                    publish_result_to_http_reply(Message, Res)
+                end,
+                Messages
+            ),
+            publish_results_to_http_reply(ResList);
+        {error, Reason} ->
+            {?BAD_REQUEST, make_bad_req_reply(Reason)}
     end.
 
+make_bad_req_reply(invalid_topic_name) ->
+    make_publish_error_response(?RC_TOPIC_NAME_INVALID);
+make_bad_req_reply(packet_too_large) ->
+    %% 0x95 RC_PACKET_TOO_LARGE is not a PUBACK reason code
+    %% This is why we use RC_QUOTA_EXCEEDED instead
+    make_publish_error_response(?RC_QUOTA_EXCEEDED, packet_too_large);
+make_bad_req_reply(Reason) ->
+    make_publish_error_response(?RC_IMPLEMENTATION_SPECIFIC_ERROR, to_binary(Reason)).
+
+-spec is_ok_deliver({_NodeOrShare, _MatchedTopic, emqx_types:deliver_result()}) -> boolean().
+is_ok_deliver({_NodeOrShare, _MatchedTopic, ok}) -> true;
+is_ok_deliver({_NodeOrShare, _MatchedTopic, {ok, _}}) -> true;
+is_ok_deliver({_NodeOrShare, _MatchedTopic, {error, _}}) -> false.
+
+%% @hidden Map MQTT publish result reason code to HTTP status code.
+%% MQTT reason code | Description                           | HTTP status code
+%% 0                  Success                                 200
+%% 16                 No matching subscribers                 202
+%% 128                Unspecified error                       406
+%% 131                Implementation specific error           406
+%% 144                Topic Name invalid                      400
+%% 151                Quota exceeded                          400
+%%
+%% %%%%%% Below error codes are not implemented so far %%%%
+%%
+%% If HTTP request passes HTTP authentication, it is considered trusted.
+%% In the future, we may choose to check ACL for the provided MQTT Client ID
+%% 135                Not authorized                          401
+%%
+%% %%%%%% Below error codes are not applicable %%%%%%%
+%%
+%% No user specified packet ID, so there should be no packet ID error
+%% 145                Packet identifier is in use             400
+%%
+%% No preceding payload format indicator to compare against.
+%% Content-Type check should be done at HTTP layer but not here.
+%% 153                Payload format invalid                  400
+publish_result_to_http_reply(_Message, []) ->
+    %% matched no subscriber
+    {?PARTIALLY_OK, make_publish_error_response(?RC_NO_MATCHING_SUBSCRIBERS)};
+publish_result_to_http_reply(Message, PublishResult) ->
+    case lists:any(fun is_ok_deliver/1, PublishResult) of
+        true ->
+            %% delivered to at least one subscriber
+            OkBody = make_publish_response(Message),
+            {?ALL_IS_WELL, OkBody};
+        false ->
+            %% this is quite unusual, matched, but failed to deliver
+            %% if this happens, the publish result log can be helpful
+            %% to idnetify the reason why publish failed
+            %% e.g. during emqx restart
+            ReasonString = <<"failed_to_dispatch">>,
+            ErrorBody = make_publish_error_response(
+                ?RC_IMPLEMENTATION_SPECIFIC_ERROR, ReasonString
+            ),
+            ?SLOG(warning, #{
+                msg => ReasonString,
+                message_id => emqx_message:id(Message),
+                results => PublishResult
+            }),
+            {?DISPATCH_ERROR, ErrorBody}
+    end.
+
+%% @hidden Reply batch publish result.
+%% 200 if all published OK.
+%% 202 if at least one message matched no subscribers.
+%% 503 for temp errors duing EMQX restart
+publish_results_to_http_reply([_ | _] = ResList) ->
+    {Codes0, BodyL} = lists:unzip(ResList),
+    Codes = lists:usort(Codes0),
+    HasFailure = lists:member(?DISPATCH_ERROR, Codes),
+    All200 = (Codes =:= [?ALL_IS_WELL]),
+    Code =
+        case All200 of
+            true ->
+                %% All OK
+                ?ALL_IS_WELL;
+            false when not HasFailure ->
+                %% Partially OK
+                ?PARTIALLY_OK;
+            false ->
+                %% At least one failed
+                ?DISPATCH_ERROR
+        end,
+    {Code, BodyL}.
+
 message(Map) ->
+    try
+        make_message(Map)
+    catch
+        throw:Reason ->
+            {error, Reason}
+    end.
+
+make_message(Map) ->
     Encoding = maps:get(<<"payload_encoding">>, Map, plain),
-    case encode_payload(Encoding, maps:get(<<"payload">>, Map)) of
+    case decode_payload(Encoding, maps:get(<<"payload">>, Map)) of
         {ok, Payload} ->
             From = maps:get(<<"clientid">>, Map, http_api),
             QoS = maps:get(<<"qos">>, Map, 0),
             Topic = maps:get(<<"topic">>, Map),
             Retain = maps:get(<<"retain">>, Map, false),
-            {ok, emqx_message:make(From, QoS, Topic, Payload, #{retain => Retain}, #{})};
+            try
+                _ = emqx_topic:validate(name, Topic)
+            catch
+                error:_Reason ->
+                    throw(invalid_topic_name)
+            end,
+            Message = emqx_message:make(From, QoS, Topic, Payload, #{retain => Retain}, #{}),
+            Size = emqx_message:estimate_size(Message),
+            (Size > size_limit()) andalso throw(packet_too_large),
+            {ok, Message};
         {error, R} ->
             {error, R}
     end.
 
-encode_payload(plain, Payload) ->
+%% get the global packet size limit since HTTP API does not belong to any zone.
+size_limit() ->
+    try
+        emqx_config:get([mqtt, max_packet_size])
+    catch
+        _:_ ->
+            %% leave 1000 bytes for topic name etc.
+            ?MAX_PACKET_SIZE
+    end.
+
+decode_payload(plain, Payload) ->
     {ok, Payload};
-encode_payload(base64, Payload) ->
+decode_payload(base64, Payload) ->
     try
         {ok, base64:decode(Payload)}
     catch
@@ -154,6 +322,8 @@ encode_payload(base64, Payload) ->
             {error, {decode_base64_payload_failed, Payload}}
     end.
 
+messages([]) ->
+    {errror, <<"empty_batch">>};
 messages(List) ->
     messages(List, []).
 
@@ -167,10 +337,23 @@ messages([MessageMap | List], Res) ->
             {error, R}
     end.
 
-format_message_response(Messages) when is_list(Messages) ->
-    [format_message_response(Message) || Message <- Messages];
-format_message_response(#message{id = ID}) ->
-    #{id => emqx_guid:to_hexstr(ID)}.
+make_publish_response(#message{id = ID}) ->
+    #{
+        id => emqx_guid:to_hexstr(ID)
+    }.
 
+make_publish_error_response(ReasonCode) ->
+    make_publish_error_response(ReasonCode, emqx_reason_codes:name(ReasonCode)).
+
+make_publish_error_response(ReasonCode, Msg) ->
+    #{
+        reason_code => ReasonCode,
+        message => to_binary(Msg)
+    }.
+
+to_binary(Atom) when is_atom(Atom) ->
+    atom_to_binary(Atom);
+to_binary(Msg) when is_binary(Msg) ->
+    Msg;
 to_binary(Term) ->
-    list_to_binary(io_lib:format("~p", [Term])).
+    list_to_binary(io_lib:format("~0p", [Term])).
diff --git a/apps/emqx_management/test/emqx_mgmt_api_publish_SUITE.erl b/apps/emqx_management/test/emqx_mgmt_api_publish_SUITE.erl
index b4b3aa902..0ebaf7195 100644
--- a/apps/emqx_management/test/emqx_mgmt_api_publish_SUITE.erl
+++ b/apps/emqx_management/test/emqx_mgmt_api_publish_SUITE.erl
@@ -19,6 +19,7 @@
 -compile(nowarn_export_all).
 
 -include_lib("eunit/include/eunit.hrl").
+-include_lib("emqx/include/emqx_mqtt.hrl").
 
 -define(CLIENTID, <<"api_clientid">>).
 -define(USERNAME, <<"api_username">>).
@@ -36,6 +37,16 @@ init_per_suite(Config) ->
 end_per_suite(_) ->
     emqx_mgmt_api_test_util:end_suite().
 
+init_per_testcase(Case, Config) ->
+    ?MODULE:Case({init, Config}).
+
+end_per_testcase(Case, Config) ->
+    ?MODULE:Case({'end', Config}).
+
+t_publish_api({init, Config}) ->
+    Config;
+t_publish_api({'end', _Config}) ->
+    ok;
 t_publish_api(_) ->
     {ok, Client} = emqtt:start_link(#{
         username => <<"api_username">>, clientid => <<"api_clientid">>
@@ -48,11 +59,113 @@ t_publish_api(_) ->
     Auth = emqx_mgmt_api_test_util:auth_header_(),
     Body = #{topic => ?TOPIC1, payload => Payload},
     {ok, Response} = emqx_mgmt_api_test_util:request_api(post, Path, "", Auth, Body),
-    ResponseMap = emqx_json:decode(Response, [return_maps]),
-    ?assertEqual([<<"id">>], maps:keys(ResponseMap)),
+    ResponseMap = decode_json(Response),
+    ?assertEqual([<<"id">>], lists:sort(maps:keys(ResponseMap))),
     ?assertEqual(ok, receive_assert(?TOPIC1, 0, Payload)),
-    emqtt:disconnect(Client).
+    emqtt:stop(Client).
 
+t_publish_no_subscriber({init, Config}) ->
+    Config;
+t_publish_no_subscriber({'end', _Config}) ->
+    ok;
+t_publish_no_subscriber(_) ->
+    Payload = <<"hello">>,
+    Path = emqx_mgmt_api_test_util:api_path(["publish"]),
+    Auth = emqx_mgmt_api_test_util:auth_header_(),
+    Body = #{topic => ?TOPIC1, payload => Payload},
+    {ok, Response} = emqx_mgmt_api_test_util:request_api(post, Path, "", Auth, Body),
+    ResponseMap = decode_json(Response),
+    ?assertEqual([<<"message">>, <<"reason_code">>], lists:sort(maps:keys(ResponseMap))),
+    ?assertMatch(#{<<"reason_code">> := ?RC_NO_MATCHING_SUBSCRIBERS}, ResponseMap),
+    ok.
+
+t_publish_bad_topic({init, Config}) ->
+    Config;
+t_publish_bad_topic({'end', _Config}) ->
+    ok;
+t_publish_bad_topic(_) ->
+    Payload = <<"hello">>,
+    Path = emqx_mgmt_api_test_util:api_path(["publish"]),
+    Auth = emqx_mgmt_api_test_util:auth_header_(),
+    Body = #{topic => <<"not/a+/valid/topic">>, payload => Payload},
+    ?assertMatch(
+        {error, {_, 400, _}}, emqx_mgmt_api_test_util:request_api(post, Path, "", Auth, Body)
+    ).
+
+t_publish_bad_base64({init, Config}) ->
+    Config;
+t_publish_bad_base64({'end', _Config}) ->
+    ok;
+t_publish_bad_base64(_) ->
+    %% not a valid base64
+    Payload = <<"hello">>,
+    Path = emqx_mgmt_api_test_util:api_path(["publish"]),
+    Auth = emqx_mgmt_api_test_util:auth_header_(),
+    Body = #{
+        topic => <<"not/a+/valid/topic">>, payload => Payload, payload_encoding => <<"base64">>
+    },
+    ?assertMatch(
+        {error, {_, 400, _}}, emqx_mgmt_api_test_util:request_api(post, Path, "", Auth, Body)
+    ).
+
+t_publish_too_large({init, Config}) ->
+    MaxPacketSize = 100,
+    meck:new(emqx_config, [no_link, passthrough, no_history]),
+    meck:expect(emqx_config, get, fun
+        ([mqtt, max_packet_size]) ->
+            MaxPacketSize;
+        (Other) ->
+            meck:passthrough(Other)
+    end),
+    [{max_packet_size, MaxPacketSize} | Config];
+t_publish_too_large({'end', _Config}) ->
+    meck:unload(emqx_config),
+    ok;
+t_publish_too_large(Config) ->
+    MaxPacketSize = proplists:get_value(max_packet_size, Config),
+    Payload = lists:duplicate(MaxPacketSize, $0),
+    Path = emqx_mgmt_api_test_util:api_path(["publish"]),
+    Auth = emqx_mgmt_api_test_util:auth_header_(),
+    Body = #{topic => <<"random/topic">>, payload => Payload},
+    {error, {Summary, _Headers, ResponseBody}} =
+        emqx_mgmt_api_test_util:request_api(
+            post,
+            Path,
+            "",
+            Auth,
+            Body,
+            #{return_body => true}
+        ),
+    ?assertMatch({_, 400, _}, Summary),
+    ?assertMatch(
+        #{
+            <<"reason_code">> := ?RC_QUOTA_EXCEEDED,
+            <<"message">> := <<"packet_too_large">>
+        },
+        decode_json(ResponseBody)
+    ),
+    ok.
+
+t_publish_bad_topic_bulk({init, Config}) ->
+    Config;
+t_publish_bad_topic_bulk({'end', _Config}) ->
+    ok;
+t_publish_bad_topic_bulk(_Config) ->
+    Payload = <<"hello">>,
+    Path = emqx_mgmt_api_test_util:api_path(["publish", "bulk"]),
+    Auth = emqx_mgmt_api_test_util:auth_header_(),
+    Body = [
+        #{topic => <<"not/a+/valid/topic">>, payload => Payload},
+        #{topic => <<"good/topic">>, payload => Payload}
+    ],
+    ?assertMatch(
+        {error, {_, 400, _}}, emqx_mgmt_api_test_util:request_api(post, Path, "", Auth, Body)
+    ).
+
+t_publish_bulk_api({init, Config}) ->
+    Config;
+t_publish_bulk_api({'end', _Config}) ->
+    ok;
 t_publish_bulk_api(_) ->
     {ok, Client} = emqtt:start_link(#{
         username => <<"api_username">>, clientid => <<"api_clientid">>
@@ -63,19 +176,135 @@ t_publish_bulk_api(_) ->
     Payload = <<"hello">>,
     Path = emqx_mgmt_api_test_util:api_path(["publish", "bulk"]),
     Auth = emqx_mgmt_api_test_util:auth_header_(),
-    Body = [#{topic => ?TOPIC1, payload => Payload}, #{topic => ?TOPIC2, payload => Payload}],
+    Body = [
+        #{
+            topic => ?TOPIC1,
+            payload => Payload,
+            payload_encoding => plain
+        },
+        #{
+            topic => ?TOPIC2,
+            payload => base64:encode(Payload),
+            payload_encoding => base64
+        }
+    ],
     {ok, Response} = emqx_mgmt_api_test_util:request_api(post, Path, "", Auth, Body),
-    ResponseList = emqx_json:decode(Response, [return_maps]),
+    ResponseList = decode_json(Response),
     ?assertEqual(2, erlang:length(ResponseList)),
     lists:foreach(
         fun(ResponseMap) ->
-            ?assertEqual([<<"id">>], maps:keys(ResponseMap))
+            ?assertMatch(
+                [<<"id">>], lists:sort(maps:keys(ResponseMap))
+            )
         end,
         ResponseList
     ),
     ?assertEqual(ok, receive_assert(?TOPIC1, 0, Payload)),
     ?assertEqual(ok, receive_assert(?TOPIC2, 0, Payload)),
-    emqtt:disconnect(Client).
+    emqtt:stop(Client).
+
+t_publish_no_subscriber_bulk({init, Config}) ->
+    Config;
+t_publish_no_subscriber_bulk({'end', _Config}) ->
+    ok;
+t_publish_no_subscriber_bulk(_) ->
+    {ok, Client} = emqtt:start_link(#{
+        username => <<"api_username">>, clientid => <<"api_clientid">>
+    }),
+    {ok, _} = emqtt:connect(Client),
+    {ok, _, [0]} = emqtt:subscribe(Client, ?TOPIC1),
+    {ok, _, [0]} = emqtt:subscribe(Client, ?TOPIC2),
+    Payload = <<"hello">>,
+    Path = emqx_mgmt_api_test_util:api_path(["publish", "bulk"]),
+    Auth = emqx_mgmt_api_test_util:auth_header_(),
+    Body = [
+        #{topic => ?TOPIC1, payload => Payload},
+        #{topic => ?TOPIC2, payload => Payload},
+        #{topic => <<"no/subscrbier/topic">>, payload => Payload}
+    ],
+    {ok, Response} = emqx_mgmt_api_test_util:request_api(post, Path, "", Auth, Body),
+    ResponseList = decode_json(Response),
+    ?assertMatch(
+        [
+            #{<<"id">> := _},
+            #{<<"id">> := _},
+            #{<<"message">> := <<"no_matching_subscribers">>}
+        ],
+        ResponseList
+    ),
+    ?assertEqual(ok, receive_assert(?TOPIC1, 0, Payload)),
+    ?assertEqual(ok, receive_assert(?TOPIC2, 0, Payload)),
+    emqtt:stop(Client).
+
+t_publish_bulk_dispatch_one_message_invalid_topic({init, Config}) ->
+    Config;
+t_publish_bulk_dispatch_one_message_invalid_topic({'end', _Config}) ->
+    ok;
+t_publish_bulk_dispatch_one_message_invalid_topic(Config) when is_list(Config) ->
+    Payload = <<"hello">>,
+    Path = emqx_mgmt_api_test_util:api_path(["publish", "bulk"]),
+    Auth = emqx_mgmt_api_test_util:auth_header_(),
+    Body = [
+        #{topic => ?TOPIC1, payload => Payload},
+        #{topic => ?TOPIC2, payload => Payload},
+        #{topic => <<"bad/#/topic">>, payload => Payload}
+    ],
+    {error, {Summary, _Headers, ResponseBody}} =
+        emqx_mgmt_api_test_util:request_api(
+            post,
+            Path,
+            "",
+            Auth,
+            Body,
+            #{return_body => true}
+        ),
+    ?assertMatch({_, 400, _}, Summary),
+    ?assertMatch(
+        #{<<"reason_code">> := ?RC_TOPIC_NAME_INVALID},
+        decode_json(ResponseBody)
+    ).
+
+t_publish_bulk_dispatch_failure({init, Config}) ->
+    meck:new(emqx, [no_link, passthrough, no_history]),
+    meck:expect(emqx, is_running, fun() -> false end),
+    Config;
+t_publish_bulk_dispatch_failure({'end', _Config}) ->
+    meck:unload(emqx),
+    ok;
+t_publish_bulk_dispatch_failure(Config) when is_list(Config) ->
+    {ok, Client} = emqtt:start_link(#{
+        username => <<"api_username">>, clientid => <<"api_clientid">>
+    }),
+    {ok, _} = emqtt:connect(Client),
+    {ok, _, [0]} = emqtt:subscribe(Client, ?TOPIC1),
+    {ok, _, [0]} = emqtt:subscribe(Client, ?TOPIC2),
+    Payload = <<"hello">>,
+    Path = emqx_mgmt_api_test_util:api_path(["publish", "bulk"]),
+    Auth = emqx_mgmt_api_test_util:auth_header_(),
+    Body = [
+        #{topic => ?TOPIC1, payload => Payload},
+        #{topic => ?TOPIC2, payload => Payload},
+        #{topic => <<"no/subscrbier/topic">>, payload => Payload}
+    ],
+    {error, {Summary, _Headers, ResponseBody}} =
+        emqx_mgmt_api_test_util:request_api(
+            post,
+            Path,
+            "",
+            Auth,
+            Body,
+            #{return_body => true}
+        ),
+    ?assertMatch({_, 503, _}, Summary),
+    ?assertMatch(
+        [
+            #{<<"reason_code">> := ?RC_IMPLEMENTATION_SPECIFIC_ERROR},
+            #{<<"reason_code">> := ?RC_IMPLEMENTATION_SPECIFIC_ERROR},
+            #{<<"reason_code">> := ?RC_NO_MATCHING_SUBSCRIBERS}
+        ],
+        decode_json(ResponseBody)
+    ),
+    emqtt:stop(Client).
 
 receive_assert(Topic, Qos, Payload) ->
     receive
@@ -90,3 +319,6 @@ receive_assert(Topic, Qos, Payload) ->
     after 5000 ->
         timeout
     end.
+
+decode_json(In) ->
+    emqx_json:decode(In, [return_maps]).
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 a8b04dc80..1bc29dfee 100644
--- a/apps/emqx_management/test/emqx_mgmt_api_test_util.erl
+++ b/apps/emqx_management/test/emqx_mgmt_api_test_util.erl
@@ -65,8 +65,11 @@ request_api(Method, Url, QueryParams, AuthOrHeaders, []) when
             "" -> Url;
             _ -> Url ++ "?" ++ QueryParams
         end,
-    do_request_api(Method, {NewUrl, build_http_header(AuthOrHeaders)});
-request_api(Method, Url, QueryParams, AuthOrHeaders, Body) when
+    do_request_api(Method, {NewUrl, build_http_header(AuthOrHeaders)}, #{});
+request_api(Method, Url, QueryParams, AuthOrHeaders, Body) ->
+    request_api(Method, Url, QueryParams, AuthOrHeaders, Body, #{}).
+
+request_api(Method, Url, QueryParams, AuthOrHeaders, Body, Opts) when
     (Method =:= post) orelse
         (Method =:= patch) orelse
         (Method =:= put) orelse
@@ -79,10 +82,12 @@ request_api(Method, Url, QueryParams, AuthOrHeaders, Body) when
         end,
     do_request_api(
         Method,
-        {NewUrl, build_http_header(AuthOrHeaders), "application/json", emqx_json:encode(Body)}
+        {NewUrl, build_http_header(AuthOrHeaders), "application/json", emqx_json:encode(Body)},
+        Opts
     ).
 
-do_request_api(Method, Request) ->
+do_request_api(Method, Request, Opts) ->
+    ReturnBody = maps:get(return_body, Opts, false),
     ct:pal("Method: ~p, Request: ~p", [Method, Request]),
     case httpc:request(Method, Request, [], []) of
         {error, socket_closed_remotely} ->
@@ -91,8 +96,9 @@ do_request_api(Method, Request) ->
             Code >= 200 andalso Code =< 299
         ->
             {ok, Return};
-        {ok, {Reason, _, _} = Error} ->
-            ct:pal("error: ~p~n", [Error]),
+        {ok, {Reason, Headers, Body}} when ReturnBody ->
+            {error, {Reason, Headers, Body}};
+        {ok, {Reason, _Headers, _Body}} ->
             {error, Reason}
     end.
 

From 72a228c52136f5a3ce1ec3d6e27ed91a7306513c Mon Sep 17 00:00:00 2001
From: JianBo He <heeejianbo@163.com>
Date: Fri, 21 Oct 2022 09:53:31 +0800
Subject: [PATCH 07/13] chore: update apps/emqx/i18n/emqx_schema_i18n.conf

Co-authored-by: Zaiming (Stone) Shi <zmstone@gmail.com>
---
 apps/emqx/i18n/emqx_schema_i18n.conf | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/apps/emqx/i18n/emqx_schema_i18n.conf b/apps/emqx/i18n/emqx_schema_i18n.conf
index ae9da4579..81e9c96dc 100644
--- a/apps/emqx/i18n/emqx_schema_i18n.conf
+++ b/apps/emqx/i18n/emqx_schema_i18n.conf
@@ -869,7 +869,7 @@ When set to true, invalid utf8 strings in for example client ID, topic name, etc
 
     mqtt_max_awaiting_rel {
         desc {
-            en: """EMQX creates a wait queue in the client's session to accept QoS 2 messages from the client until this QoS 2 message transmission is complete or is discarded due to timeout.</br>
+            en: """For each publisher session, the maximum number of outstanding QoS 2 messages pending on the client to send PUBREL. After reaching this limit, new QoS 2 PUBLISH requests will be rejected with reason code `147(0x93)` until either PUBREL is received or timed out.</br>
 After this queue is full, the processing of QoS 2 messages will be stopped."""
             zh: """EMQX 会在客户端的会话中创建一个等待队列来接受客户端的 QoS 2 消息，直到这条 QoS 2 消息传输完成或由于超时被丢弃。</br>
 该队列满后会停止处理 QoS 2 消息。"""

From 6d232fda5c1a2a99f5fc606013e34ddcf97f0933 Mon Sep 17 00:00:00 2001
From: JianBo He <heeejianbo@gmail.com>
Date: Fri, 21 Oct 2022 10:27:20 +0800
Subject: [PATCH 08/13] chore(i18n): improve the max_awaiting_rel desc

---
 apps/emqx/i18n/emqx_schema_i18n.conf | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/apps/emqx/i18n/emqx_schema_i18n.conf b/apps/emqx/i18n/emqx_schema_i18n.conf
index 81e9c96dc..5e4823992 100644
--- a/apps/emqx/i18n/emqx_schema_i18n.conf
+++ b/apps/emqx/i18n/emqx_schema_i18n.conf
@@ -869,10 +869,8 @@ When set to true, invalid utf8 strings in for example client ID, topic name, etc
 
     mqtt_max_awaiting_rel {
         desc {
-            en: """For each publisher session, the maximum number of outstanding QoS 2 messages pending on the client to send PUBREL. After reaching this limit, new QoS 2 PUBLISH requests will be rejected with reason code `147(0x93)` until either PUBREL is received or timed out.</br>
-After this queue is full, the processing of QoS 2 messages will be stopped."""
-            zh: """EMQX 会在客户端的会话中创建一个等待队列来接受客户端的 QoS 2 消息，直到这条 QoS 2 消息传输完成或由于超时被丢弃。</br>
-该队列满后会停止处理 QoS 2 消息。"""
+            en: """For each publisher session, the maximum number of outstanding QoS 2 messages pending on the client to send PUBREL. After reaching this limit, new QoS 2 PUBLISH requests will be rejected with reason code `147(0x93)` until either PUBREL is received or timed out."""
+            zh: """每个发布者的会话中，都存在一个队列来处理客户端发送的 QoS 2 消息。该队列会存储 QoS 2 消息的报文 ID 直到收到客户端的 PUBREL 或超时，达到队列长度的限制后，新的 QoS 2 消息发布会被拒绝，并返回 `147(0x93)` 错误。"""
         }
         label: {
             en: """Max Awaiting PUBREL"""

From 49dd25cb1438e24603b852e2fab6c711d7aeb802 Mon Sep 17 00:00:00 2001
From: JianBo He <heeejianbo@gmail.com>
Date: Fri, 21 Oct 2022 14:38:46 +0800
Subject: [PATCH 09/13] chore: make spellcheck happy

---
 apps/emqx/i18n/emqx_schema_i18n.conf | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/apps/emqx/i18n/emqx_schema_i18n.conf b/apps/emqx/i18n/emqx_schema_i18n.conf
index 5e4823992..e0a8e2995 100644
--- a/apps/emqx/i18n/emqx_schema_i18n.conf
+++ b/apps/emqx/i18n/emqx_schema_i18n.conf
@@ -869,7 +869,7 @@ When set to true, invalid utf8 strings in for example client ID, topic name, etc
 
     mqtt_max_awaiting_rel {
         desc {
-            en: """For each publisher session, the maximum number of outstanding QoS 2 messages pending on the client to send PUBREL. After reaching this limit, new QoS 2 PUBLISH requests will be rejected with reason code `147(0x93)` until either PUBREL is received or timed out."""
+            en: """For each publisher session, the maximum number of outstanding QoS 2 messages pending on the client to send PUBREL. After reaching this limit, new QoS 2 PUBLISH requests will be rejected with `147(0x93)` until either PUBREL is received or timed out."""
             zh: """每个发布者的会话中，都存在一个队列来处理客户端发送的 QoS 2 消息。该队列会存储 QoS 2 消息的报文 ID 直到收到客户端的 PUBREL 或超时，达到队列长度的限制后，新的 QoS 2 消息发布会被拒绝，并返回 `147(0x93)` 错误。"""
         }
         label: {

From 0f03449b43ae30a9d714ec4c8a194f379c7fabbb Mon Sep 17 00:00:00 2001
From: JianBo He <heeejianbo@163.com>
Date: Fri, 21 Oct 2022 16:08:09 +0800
Subject: [PATCH 10/13] chore: improve max_awating_rel_timeout conf docs

Co-authored-by: Zaiming (Stone) Shi <zmstone@gmail.com>
---
 apps/emqx/i18n/emqx_schema_i18n.conf | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/apps/emqx/i18n/emqx_schema_i18n.conf b/apps/emqx/i18n/emqx_schema_i18n.conf
index e0a8e2995..d4dae31c7 100644
--- a/apps/emqx/i18n/emqx_schema_i18n.conf
+++ b/apps/emqx/i18n/emqx_schema_i18n.conf
@@ -880,8 +880,8 @@ When set to true, invalid utf8 strings in for example client ID, topic name, etc
 
     mqtt_await_rel_timeout {
         desc {
-            en: """The QoS 2 messages (Client -> Broker) handle flow will be ignored if awaiting PUBREL timeout. This QoS 2 message can be published successfully."""
-            zh: """如果等待 PUBREL 超时，QoS 2消息（Client -> Broker）处理流程将被忽略。这条 QoS 2 仍然会成功发布。"""
+            en: """For client to broker QoS 2 message, the time limit for the broker to wait before the `PUBREL` message is received. The wait is aborted after timed out, and receiving a stale `PUBREL` causes a warning level log. Note, the message is delivered to subscribers before entering the wait for PUBREL."""
+            zh: """客户端发布 QoS 2 消息时，服务器等待 `PUBREL` 的最长时延。超过该时长后服务器会放弃等待，如果在这之后收到 PUBREL，服务器将会产生一条告警日志。注意，向订阅客户端转发消息的动作发生在进入等待之前。"""
         }
         label: {
             en: """Max Awaiting PUBREL TIMEOUT"""

From ca052bd0f4559df7b7b647ce1a0257e79eaf8c61 Mon Sep 17 00:00:00 2001
From: "Zaiming (Stone) Shi" <zmstone@gmail.com>
Date: Fri, 21 Oct 2022 17:28:49 +0200
Subject: [PATCH 11/13] docs: Update apps/emqx/i18n/emqx_schema_i18n.conf

---
 apps/emqx/i18n/emqx_schema_i18n.conf | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/apps/emqx/i18n/emqx_schema_i18n.conf b/apps/emqx/i18n/emqx_schema_i18n.conf
index d4dae31c7..94aae19cf 100644
--- a/apps/emqx/i18n/emqx_schema_i18n.conf
+++ b/apps/emqx/i18n/emqx_schema_i18n.conf
@@ -880,8 +880,8 @@ When set to true, invalid utf8 strings in for example client ID, topic name, etc
 
     mqtt_await_rel_timeout {
         desc {
-            en: """For client to broker QoS 2 message, the time limit for the broker to wait before the `PUBREL` message is received. The wait is aborted after timed out, and receiving a stale `PUBREL` causes a warning level log. Note, the message is delivered to subscribers before entering the wait for PUBREL."""
-            zh: """客户端发布 QoS 2 消息时，服务器等待 `PUBREL` 的最长时延。超过该时长后服务器会放弃等待，如果在这之后收到 PUBREL，服务器将会产生一条告警日志。注意，向订阅客户端转发消息的动作发生在进入等待之前。"""
+            en: """For client to broker QoS 2 message, the time limit for the broker to wait before the `PUBREL` message is received. The wait is aborted after timed out, meaning the packet ID is freed for new `PUBLISH` requests. Receiving a stale `PUBREL` causes a warning level log. Note, the message is delivered to subscribers before entering the wait for PUBREL."""
+            zh: """客户端发布 QoS 2 消息时，服务器等待 `PUBREL` 的最长时延。超过该时长后服务器会放弃等待，该PACKET ID 会被释放，从而允许后续新的 PUBLISH 消息使用。如果超时后收到 PUBREL，服务器将会产生一条告警日志。注意，向订阅客户端转发消息的动作发生在进入等待之前。"""
         }
         label: {
             en: """Max Awaiting PUBREL TIMEOUT"""

From 31c0d73cd5239827a9dc35bc82cdf78aa07a39a3 Mon Sep 17 00:00:00 2001
From: "Zaiming (Stone) Shi" <zmstone@gmail.com>
Date: Thu, 20 Oct 2022 18:45:17 +0200
Subject: [PATCH 12/13] chore: split change logs

---
 CHANGES-5.0.md       | 205 -------------------------------------------
 changes/v5.0.1-en.md |  53 +++++++++++
 changes/v5.0.2-en.md |  18 ++++
 changes/v5.0.3-en.md |  12 +++
 changes/v5.0.4-en.md |  37 ++++++++
 changes/v5.0.5-en.md |  17 ++++
 changes/v5.0.6-en.md |   5 ++
 changes/v5.0.7-en.md |  12 +++
 changes/v5.0.8-en.md |  28 ++++++
 changes/v5.0.9-en.md |  34 +++++++
 changes/v5.0.9-zh.md |  28 ++++++
 11 files changed, 244 insertions(+), 205 deletions(-)
 delete mode 100644 CHANGES-5.0.md
 create mode 100644 changes/v5.0.1-en.md
 create mode 100644 changes/v5.0.2-en.md
 create mode 100644 changes/v5.0.3-en.md
 create mode 100644 changes/v5.0.4-en.md
 create mode 100644 changes/v5.0.5-en.md
 create mode 100644 changes/v5.0.6-en.md
 create mode 100644 changes/v5.0.7-en.md
 create mode 100644 changes/v5.0.8-en.md
 create mode 100644 changes/v5.0.9-en.md
 create mode 100644 changes/v5.0.9-zh.md

diff --git a/CHANGES-5.0.md b/CHANGES-5.0.md
deleted file mode 100644
index d75766f0b..000000000
--- a/CHANGES-5.0.md
+++ /dev/null
@@ -1,205 +0,0 @@
-# 5.0.9
-
-## Enhancements
-
-* Add `cert_common_name` and `cert_subject` placeholder support for authz_http and authz_mongo.[#8973](https://github.com/emqx/emqx/pull/8973)
-* Use milliseconds internally in emqx_delayed to store the publish time, improving precision.[#9060](https://github.com/emqx/emqx/pull/9060)
-* More rigorous checking of flapping to improve stability of the system. [#9136](https://github.com/emqx/emqx/pull/9136)
-* No message(s) echo for the message publish APIs [#9155](https://github.com/emqx/emqx/pull/9155)
-  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.
-
-## Bug fixes
-
-* Check ACLs for last will testament topic before publishing the message. [#8930](https://github.com/emqx/emqx/pull/8930)
-* Fix GET /listeners API crash When some nodes still in initial configuration. [#9002](https://github.com/emqx/emqx/pull/9002)
-* Fix empty variable interpolation in authentication and authorization. Placeholders for undefined variables are rendered now as empty strings and do not cause errors anymore. [#8963](https://github.com/emqx/emqx/pull/8963)
-* Fix the latency statistics error of the slow subscription module when `stats_type` is `internal` or `response`. [#8986](https://github.com/emqx/emqx/pull/8986)
-* Redispatch shared subscription messages. [#9104](https://github.com/emqx/emqx/pull/9104)
-
-# 5.0.8
-
-## Bug fixes
-
-* Fix exhook `client.authorize` never being execauted. [#8780](https://github.com/emqx/emqx/pull/8780)
-* Fix JWT plugin don't support non-integer timestamp claims. [#8867](https://github.com/emqx/emqx/pull/8867)
-* Avoid publishing will message when client fails to auhtenticate. [#8887](https://github.com/emqx/emqx/pull/8887)
-* Speed up dispatching of shared subscription messages in a cluster [#8893](https://github.com/emqx/emqx/pull/8893)
-* Fix the extra / prefix when CoAP gateway parsing client topics. [#8658](https://github.com/emqx/emqx/pull/8658)
-* Speed up updating the configuration, When some nodes in the cluster are down. [#8857](https://github.com/emqx/emqx/pull/8857)
-* Fix delayed publish inaccurate caused by os time change. [#8926](https://github.com/emqx/emqx/pull/8926)
-* Fix that EMQX can't start when the retainer is disabled [#8911](https://github.com/emqx/emqx/pull/8911)
-* Fix that redis authn will deny the unknown users [#8934](https://github.com/emqx/emqx/pull/8934)
-* Fix ExProto UDP client keepalive checking error.
-  This causes the clients to not expire as long as a new UDP packet arrives [#8866](https://github.com/emqx/emqx/pull/8866)
-* Fix that MQTT Bridge message payload could be empty string. [#8949](https://github.com/emqx/emqx/pull/8949)
-
-## Enhancements
-
-* Print a warning message when boot with the default (insecure) Erlang cookie. [#8905](https://github.com/emqx/emqx/pull/8905)
-* Change the `/gateway` API path to plural form. [#8823](https://github.com/emqx/emqx/pull/8823)
-* Don't allow updating config items when they already exist in `local-override.conf`. [#8851](https://github.com/emqx/emqx/pull/8851)
-* Remove `node.etc_dir` from emqx.conf, because it is never used.
-  Also allow user to customize the logging directory [#8892](https://github.com/emqx/emqx/pull/8892)
-* Added a new API `POST /listeners` for creating listener. [#8876](https://github.com/emqx/emqx/pull/8876)
-* Close ExProto client process immediately if it's keepalive timeouted. [#8866](https://github.com/emqx/emqx/pull/8866)
-* Upgrade grpc-erl driver to 0.6.7 to support batch operation in sending stream. [#8866](https://github.com/emqx/emqx/pull/8866)
-
-# 5.0.7
-
-## Bug fixes
-
-* Remove `will_msg` (not used) field from the client API. [#8721](https://github.com/emqx/emqx/pull/8721)
-* Fix `$queue` topic name error in management API return. [#8728](https://github.com/emqx/emqx/pull/8728)
-* Fix race condition which may cause `client.connected` and `client.disconnected` out of order. [#8625](https://github.com/emqx/emqx/pull/8625)
-* Fix quic listener default idle timeout's type. [#8826](https://github.com/emqx/emqx/pull/8826)
-
-## Enhancements
-
-* Do not auto-populate default SSL cipher suites, so that the configs are less bloated. [#8769](https://github.com/emqx/emqx/pull/8769)
-
-# 5.0.6
-
-## Bug fixes
-
-* Upgrade Dashboard version to fix an issue where the node status was not displayed correctly. [#8771](https://github.com/emqx/emqx/pull/8771)
-
-# 5.0.5
-
-## Bug fixes
-
-* Allow changing the license type from key to file (and vice-versa). [#8598](https://github.com/emqx/emqx/pull/8598)
-* Add back http connector config keys `max_retries` `retry_interval` as deprecated fields [#8672](https://github.com/emqx/emqx/issues/8672)
-  This caused upgrade failure in 5.0.4, because it would fail to boot on configs created from older version.
-
-## Enhancements
-
-* Add `bootstrap_users_file` configuration to add default Dashboard username list, which is only added when EMQX is first started.
-* The license is now copied to all nodes in the cluster when it's reloaded. [#8598](https://github.com/emqx/emqx/pull/8598)
-* Added a HTTP API to manage licenses. [#8610](https://github.com/emqx/emqx/pull/8610)
-* Updated `/nodes` API node_status from `Running/Stopped` to `running/stopped`. [#8642](https://github.com/emqx/emqx/pull/8642)
-* Improve handling of placeholder interpolation errors [#8635](https://github.com/emqx/emqx/pull/8635)
-* Better logging on unknown object IDs. [#8670](https://github.com/emqx/emqx/pull/8670)
-* The bind option support `:1883` style. [#8758](https://github.com/emqx/emqx/pull/8758)
-
-# 5.0.4
-
-## Bug fixes
-
-* The `data/configs/cluster-override.conf` is cleared to 0KB if `hocon_pp:do/2` failed [commits/71f64251](https://github.com/emqx/emqx/pull/8443/commits/71f642518a683cc91a32fd542aafaac6ef915720)
-* Improve the health_check for webhooks.
-  Prior to this change, the webhook only checks the connectivity of the TCP port using `gen_tcp:connect/2`, so
-  if it's a HTTPs server, we didn't check if TLS handshake was successful.
-  [commits/6b45d2ea](https://github.com/emqx/emqx/commit/6b45d2ea9fde6d3b4a5b007f7a8c5a1c573d141e)
-* The `created_at` field of rules is missing after emqx restarts. [commits/5fc09e6b](https://github.com/emqx/emqx/commit/5fc09e6b950c340243d7be627a0ce1700691221c)
-* The rule engine's jq function now works even when the path to the EMQX install dir contains spaces [jq#35](https://github.com/emqx/jq/pull/35) [#8455](https://github.com/emqx/emqx/pull/8455)
-* Avoid applying any ACL checks on superusers [#8452](https://github.com/emqx/emqx/pull/8452)
-* Fix statistics related system topic name error
-* Fix AuthN JWKS SSL schema. Using schema in `emqx_schema`. [#8458](https://github.com/emqx/emqx/pull/8458)
-* `sentinel` field should be required when AuthN/AuthZ Redis using sentinel mode. [#8458](https://github.com/emqx/emqx/pull/8458)
-* Fix bad swagger format. [#8517](https://github.com/emqx/emqx/pull/8517)
-* Fix `chars_limit` is not working when `formatter` is `json`. [#8518](http://github.com/emqx/emqx/pull/8518)
-* Ensuring that exhook dispatches the client events are sequential. [#8530](https://github.com/emqx/emqx/pull/8530)
-* Avoid using RocksDB backend for persistent sessions when such backend is unavailable. [#8528](https://github.com/emqx/emqx/pull/8528)
-* Fix AuthN `cert_subject` and `cert_common_name` placeholder rendering failure. [#8531](https://github.com/emqx/emqx/pull/8531)
-* Support listen on an IPv6 address, e.g: [::1]:1883 or ::1:1883. [#8547](https://github.com/emqx/emqx/pull/8547)
-* GET '/rules' support for pagination and fuzzy search. [#8472](https://github.com/emqx/emqx/pull/8472)
-  **‼️ Note** : The previous API only returns array: `[RuleObj1,RuleObj2]`, after updating, it will become
-  `{"data": [RuleObj1,RuleObj2], "meta":{"count":2, "limit":100, "page":1}`,
-  which will carry the paging meta information.
-* Fix the issue that webhook leaks TCP connections. [ehttpc#34](https://github.com/emqx/ehttpc/pull/34), [#8580](https://github.com/emqx/emqx/pull/8580)
-
-## Enhancements
-
-* Improve the dashboard listener startup log, the listener name is no longer spliced with port information,
-  and the colon(:) is no longer displayed when IP is not specified. [#8480](https://github.com/emqx/emqx/pull/8480)
-* Remove `/configs/listeners` API, use `/listeners/` instead. [#8485](https://github.com/emqx/emqx/pull/8485)
-* Optimize performance of builtin database operations in processes with long message queue [#8439](https://github.com/emqx/emqx/pull/8439)
-* Improve authentication tracing. [#8554](https://github.com/emqx/emqx/pull/8554)
-* Standardize the '/listeners' and `/gateway/<name>/listeners` API fields.
-  It will introduce some incompatible updates, see [#8571](https://github.com/emqx/emqx/pull/8571)
-* Add option to perform GC on connection process after TLS/SSL handshake is performed. [#8637](https://github.com/emqx/emqx/pull/8637)
-
-# 5.0.3
-
-## Bug fixes
-
-* Websocket listener failed to read headers `X-Forwarded-For` and `X-Forwarded-Port` [#8415](https://github.com/emqx/emqx/pull/8415)
-* Deleted `cluster_singleton` from MQTT bridge config document. This config is no longer applicable in 5.0 [#8407](https://github.com/emqx/emqx/pull/8407)
-* Fix `emqx/emqx:latest` docker image publish to use the Erlang flavor, but not Elixir flavor [#8414](https://github.com/emqx/emqx/pull/8414)
-* Changed the `exp` field in JWT auth to be optional rather than required to fix backwards compatability with 4.X releases. [#8425](https://github.com/emqx/emqx/pull/8425)
-
-## Enhancements
-
-* Improve the speed of dashboard's HTTP API routing rule generation, which sometimes causes timeout [#8438](https://github.com/emqx/emqx/pull/8438)
-
-# 5.0.2
-
-Announcement: EMQX team has decided to stop supporting relup for opensource edition.
-Going forward, it will be an enterprise-only feature.
-
-Main reason: relup requires carefully crafted upgrade instructions from ALL previous versions.
-
-For example, 4.3 is now at 4.3.16, we have `4.3.0->4.3.16`, `4.3.1->4.3.16`, ... 16 such upgrade paths in total to maintain.
-This had been the biggest obstacle for EMQX team to act agile enough in delivering enhancements and fixes.
-
-## Enhancements
-
-## Bug fixes
-
-* Fixed a typo in `bin/emqx` which affects MacOs release when trying to enable Erlang distribution over TLS [#8398](https://github.com/emqx/emqx/pull/8398)
-* Restricted shell was accidentally disabled in 5.0.1, it has been added back. [#8396](https://github.com/emqx/emqx/pull/8396)
-
-# 5.0.1
-
-5.0.1 is built on [Erlang/OTP 24.2.1-1](https://github.com/emqx/otp/tree/OTP-24.2.1-1). Same as 5.0.0.
-
-5.0.0 (like 4.4.x) had Erlang/OTP version number in the package name.
-This is because we wanted to release different flavor packages (on different Elixir/Erlang/OTP platforms).
-
-However the long package names also causes confusion, as users may not know which to choose if there were more than
-one presented at the same time.
-
-Going forward, (starting from 5.0.1), packages will be released in both default (short) and flavored (long) package names.
-
-For example: `emqx-5.0.1-otp24.2.1-1-ubuntu20.04-amd64.tar.gz`,
-but only the default one is presented to the users: `emqx-5.0.1-ubuntu20.04-amd64.tar.gz`.
-
-In case anyone wants to try a different flavor package, it can be downlowded from the public s3 bucket,
-for example:
-https://s3.us-west-2.amazonaws.com/packages.emqx/emqx-ce/v5.0.1/emqx-5.0.1-otp24.2.1-1-ubuntu20.04-arm64.tar.gz
-
-Exceptions:
-
-* Windows package is always presented with short name (currently on Erlang/OTP 24.2.1).
-* Elixir package name is flavored with both Elixir and Erlang/OTP version numbers,
-  for example: `emqx-5.0.1-elixir1.13.4-otp24.2.1-1-ubuntu20.04-amd64.tar.gz`
-
-## Enhancements
-
-* Removed management API auth for prometheus scraping endpoint /api/v5/prometheus/stats [#8299](https://github.com/emqx/emqx/pull/8299)
-* Added more TCP options for exhook (gRPC) connections. [#8317](https://github.com/emqx/emqx/pull/8317)
-* HTTP Servers used for authentication and authorization will now indicate the result via the response body. [#8374](https://github.com/emqx/emqx/pull/8374) [#8377](https://github.com/emqx/emqx/pull/8377)
-* Bulk subscribe/unsubscribe APIs [#8356](https://github.com/emqx/emqx/pull/8356)
-* Added exclusive subscription [#8315](https://github.com/emqx/emqx/pull/8315)
-* Provide authentication counter metrics [#8352](https://github.com/emqx/emqx/pull/8352) [#8375](https://github.com/emqx/emqx/pull/8375)
-* Do not allow admin user self-deletion [#8286](https://github.com/emqx/emqx/pull/8286)
-* After restart, ensure to copy `cluster-override.conf` from the clustered node which has the greatest `tnxid`. [#8333](https://github.com/emqx/emqx/pull/8333)
-
-## Bug fixes
-
-* A bug fix ported from 4.x: allow deleting subscriptions from `client.subscribe` hookpoint callback result. [#8304](https://github.com/emqx/emqx/pull/8304) [#8347](https://github.com/emqx/emqx/pull/8377)
-* Fixed Erlang distribution over TLS [#8309](https://github.com/emqx/emqx/pull/8309)
-* Made possible to override authentication configs from environment variables [#8323](https://github.com/emqx/emqx/pull/8309)
-* Made authentication passwords in Mnesia database backward compatible to 4.x, so we can support data migration better. [#8351](https://github.com/emqx/emqx/pull/8351)
-* Fix plugins upload for rpm/deb installations [#8379](https://github.com/emqx/emqx/pull/8379)
-* Sync data/authz/acl.conf and data/certs from clustered nodes after a new node joins the cluster [#8369](https://github.com/emqx/emqx/pull/8369)
-* Ensure auto-retry of failed resources [#8371](https://github.com/emqx/emqx/pull/8371)
-* Fix the issue that the count of `packets.connack.auth_error` is inaccurate when the client uses a protocol version below MQTT v5.0 to access [#8178](https://github.com/emqx/emqx/pull/8178)
-
-## Others
-
-* Rate limiter interface is hidden so far, it's subject to a UX redesign.
-* QUIC library upgraded to 0.0.14.
-* Now the default packages will be released withot otp version number in the package name.
-* Renamed config exmpale file name in `etc` dir.
diff --git a/changes/v5.0.1-en.md b/changes/v5.0.1-en.md
new file mode 100644
index 000000000..f3c301637
--- /dev/null
+++ b/changes/v5.0.1-en.md
@@ -0,0 +1,53 @@
+# v5.0.1
+
+5.0.1 is built on [Erlang/OTP 24.2.1-1](https://github.com/emqx/otp/tree/OTP-24.2.1-1). Same as 5.0.0.
+
+5.0.0 (like 4.4.x) had Erlang/OTP version number in the package name.
+This is because we wanted to release different flavor packages (on different Elixir/Erlang/OTP platforms).
+
+However the long package names also causes confusion, as users may not know which to choose if there were more than
+one presented at the same time.
+
+Going forward, (starting from 5.0.1), packages will be released in both default (short) and flavored (long) package names.
+
+For example: `emqx-5.0.1-otp24.2.1-1-ubuntu20.04-amd64.tar.gz`,
+but only the default one is presented to the users: `emqx-5.0.1-ubuntu20.04-amd64.tar.gz`.
+
+In case anyone wants to try a different flavor package, it can be downlowded from the public s3 bucket,
+for example:
+https://s3.us-west-2.amazonaws.com/packages.emqx/emqx-ce/v5.0.1/emqx-5.0.1-otp24.2.1-1-ubuntu20.04-arm64.tar.gz
+
+Exceptions:
+
+* Windows package is always presented with short name (currently on Erlang/OTP 24.2.1).
+* Elixir package name is flavored with both Elixir and Erlang/OTP version numbers,
+  for example: `emqx-5.0.1-elixir1.13.4-otp24.2.1-1-ubuntu20.04-amd64.tar.gz`
+
+## Enhancements
+
+* Removed management API auth for prometheus scraping endpoint /api/v5/prometheus/stats [#8299](https://github.com/emqx/emqx/pull/8299)
+* Added more TCP options for exhook (gRPC) connections. [#8317](https://github.com/emqx/emqx/pull/8317)
+* HTTP Servers used for authentication and authorization will now indicate the result via the response body. [#8374](https://github.com/emqx/emqx/pull/8374) [#8377](https://github.com/emqx/emqx/pull/8377)
+* Bulk subscribe/unsubscribe APIs [#8356](https://github.com/emqx/emqx/pull/8356)
+* Added exclusive subscription [#8315](https://github.com/emqx/emqx/pull/8315)
+* Provide authentication counter metrics [#8352](https://github.com/emqx/emqx/pull/8352) [#8375](https://github.com/emqx/emqx/pull/8375)
+* Do not allow admin user self-deletion [#8286](https://github.com/emqx/emqx/pull/8286)
+* After restart, ensure to copy `cluster-override.conf` from the clustered node which has the greatest `tnxid`. [#8333](https://github.com/emqx/emqx/pull/8333)
+
+## Bug fixes
+
+* A bug fix ported from 4.x: allow deleting subscriptions from `client.subscribe` hookpoint callback result. [#8304](https://github.com/emqx/emqx/pull/8304) [#8347](https://github.com/emqx/emqx/pull/8377)
+* Fixed Erlang distribution over TLS [#8309](https://github.com/emqx/emqx/pull/8309)
+* Made possible to override authentication configs from environment variables [#8323](https://github.com/emqx/emqx/pull/8309)
+* Made authentication passwords in Mnesia database backward compatible to 4.x, so we can support data migration better. [#8351](https://github.com/emqx/emqx/pull/8351)
+* Fix plugins upload for rpm/deb installations [#8379](https://github.com/emqx/emqx/pull/8379)
+* Sync data/authz/acl.conf and data/certs from clustered nodes after a new node joins the cluster [#8369](https://github.com/emqx/emqx/pull/8369)
+* Ensure auto-retry of failed resources [#8371](https://github.com/emqx/emqx/pull/8371)
+* Fix the issue that the count of `packets.connack.auth_error` is inaccurate when the client uses a protocol version below MQTT v5.0 to access [#8178](https://github.com/emqx/emqx/pull/8178)
+
+## Others
+
+* Rate limiter interface is hidden so far, it's subject to a UX redesign.
+* QUIC library upgraded to 0.0.14.
+* Now the default packages will be released withot otp version number in the package name.
+* Renamed config exmpale file name in `etc` dir.
diff --git a/changes/v5.0.2-en.md b/changes/v5.0.2-en.md
new file mode 100644
index 000000000..92e15fe4f
--- /dev/null
+++ b/changes/v5.0.2-en.md
@@ -0,0 +1,18 @@
+# v5.0.2
+
+Announcement: EMQX team has decided to stop supporting relup for opensource edition.
+Going forward, it will be an enterprise-only feature.
+
+Main reason: relup requires carefully crafted upgrade instructions from ALL previous versions.
+
+For example, 4.3 is now at 4.3.16, we have `4.3.0->4.3.16`, `4.3.1->4.3.16`, ... 16 such upgrade paths in total to maintain.
+This had been the biggest obstacle for EMQX team to act agile enough in delivering enhancements and fixes.
+
+## Enhancements
+
+## Bug fixes
+
+* Fixed a typo in `bin/emqx` which affects MacOs release when trying to enable Erlang distribution over TLS [#8398](https://github.com/emqx/emqx/pull/8398)
+* Restricted shell was accidentally disabled in 5.0.1, it has been added back. [#8396](https://github.com/emqx/emqx/pull/8396)
+
+
diff --git a/changes/v5.0.3-en.md b/changes/v5.0.3-en.md
new file mode 100644
index 000000000..df09e1db5
--- /dev/null
+++ b/changes/v5.0.3-en.md
@@ -0,0 +1,12 @@
+# v5.0.3
+
+## Bug fixes
+
+* Websocket listener failed to read headers `X-Forwarded-For` and `X-Forwarded-Port` [#8415](https://github.com/emqx/emqx/pull/8415)
+* Deleted `cluster_singleton` from MQTT bridge config document. This config is no longer applicable in 5.0 [#8407](https://github.com/emqx/emqx/pull/8407)
+* Fix `emqx/emqx:latest` docker image publish to use the Erlang flavor, but not Elixir flavor [#8414](https://github.com/emqx/emqx/pull/8414)
+* Changed the `exp` field in JWT auth to be optional rather than required to fix backwards compatability with 4.X releases. [#8425](https://github.com/emqx/emqx/pull/8425)
+
+## Enhancements
+
+* Improve the speed of dashboard's HTTP API routing rule generation, which sometimes causes timeout [#8438](https://github.com/emqx/emqx/pull/8438)
diff --git a/changes/v5.0.4-en.md b/changes/v5.0.4-en.md
new file mode 100644
index 000000000..a2531acd1
--- /dev/null
+++ b/changes/v5.0.4-en.md
@@ -0,0 +1,37 @@
+# v5.0.4
+
+## Enhancements
+
+* Improve the dashboard listener startup log, the listener name is no longer spliced with port information,
+  and the colon(:) is no longer displayed when IP is not specified. [#8480](https://github.com/emqx/emqx/pull/8480)
+* Remove `/configs/listeners` API, use `/listeners/` instead. [#8485](https://github.com/emqx/emqx/pull/8485)
+* Optimize performance of builtin database operations in processes with long message queue [#8439](https://github.com/emqx/emqx/pull/8439)
+* Improve authentication tracing. [#8554](https://github.com/emqx/emqx/pull/8554)
+* Standardize the '/listeners' and `/gateway/<name>/listeners` API fields.
+  It will introduce some incompatible updates, see [#8571](https://github.com/emqx/emqx/pull/8571)
+* Add option to perform GC on connection process after TLS/SSL handshake is performed. [#8637](https://github.com/emqx/emqx/pull/8637)
+
+## Bug fixes
+
+* The `data/configs/cluster-override.conf` is cleared to 0KB if `hocon_pp:do/2` failed [commits/71f64251](https://github.com/emqx/emqx/pull/8443/commits/71f642518a683cc91a32fd542aafaac6ef915720)
+* Improve the health_check for webhooks.
+  Prior to this change, the webhook only checks the connectivity of the TCP port using `gen_tcp:connect/2`, so
+  if it's a HTTPs server, we didn't check if TLS handshake was successful.
+  [commits/6b45d2ea](https://github.com/emqx/emqx/commit/6b45d2ea9fde6d3b4a5b007f7a8c5a1c573d141e)
+* The `created_at` field of rules is missing after emqx restarts. [commits/5fc09e6b](https://github.com/emqx/emqx/commit/5fc09e6b950c340243d7be627a0ce1700691221c)
+* The rule engine's jq function now works even when the path to the EMQX install dir contains spaces [jq#35](https://github.com/emqx/jq/pull/35) [#8455](https://github.com/emqx/emqx/pull/8455)
+* Avoid applying any ACL checks on superusers [#8452](https://github.com/emqx/emqx/pull/8452)
+* Fix statistics related system topic name error
+* Fix AuthN JWKS SSL schema. Using schema in `emqx_schema`. [#8458](https://github.com/emqx/emqx/pull/8458)
+* `sentinel` field should be required when AuthN/AuthZ Redis using sentinel mode. [#8458](https://github.com/emqx/emqx/pull/8458)
+* Fix bad swagger format. [#8517](https://github.com/emqx/emqx/pull/8517)
+* Fix `chars_limit` is not working when `formatter` is `json`. [#8518](http://github.com/emqx/emqx/pull/8518)
+* Ensuring that exhook dispatches the client events are sequential. [#8530](https://github.com/emqx/emqx/pull/8530)
+* Avoid using RocksDB backend for persistent sessions when such backend is unavailable. [#8528](https://github.com/emqx/emqx/pull/8528)
+* Fix AuthN `cert_subject` and `cert_common_name` placeholder rendering failure. [#8531](https://github.com/emqx/emqx/pull/8531)
+* Support listen on an IPv6 address, e.g: [::1]:1883 or ::1:1883. [#8547](https://github.com/emqx/emqx/pull/8547)
+* GET '/rules' support for pagination and fuzzy search. [#8472](https://github.com/emqx/emqx/pull/8472)
+  **‼️ Note** : The previous API only returns array: `[RuleObj1,RuleObj2]`, after updating, it will become
+  `{"data": [RuleObj1,RuleObj2], "meta":{"count":2, "limit":100, "page":1}`,
+  which will carry the paging meta information.
+* Fix the issue that webhook leaks TCP connections. [ehttpc#34](https://github.com/emqx/ehttpc/pull/34), [#8580](https://github.com/emqx/emqx/pull/8580)
diff --git a/changes/v5.0.5-en.md b/changes/v5.0.5-en.md
new file mode 100644
index 000000000..9c462545d
--- /dev/null
+++ b/changes/v5.0.5-en.md
@@ -0,0 +1,17 @@
+# v5.0.5
+
+## Enhancements
+
+* Add `bootstrap_users_file` configuration to add default Dashboard username list, which is only added when EMQX is first started.
+* The license is now copied to all nodes in the cluster when it's reloaded. [#8598](https://github.com/emqx/emqx/pull/8598)
+* Added a HTTP API to manage licenses. [#8610](https://github.com/emqx/emqx/pull/8610)
+* Updated `/nodes` API node_status from `Running/Stopped` to `running/stopped`. [#8642](https://github.com/emqx/emqx/pull/8642)
+* Improve handling of placeholder interpolation errors [#8635](https://github.com/emqx/emqx/pull/8635)
+* Better logging on unknown object IDs. [#8670](https://github.com/emqx/emqx/pull/8670)
+* The bind option support `:1883` style. [#8758](https://github.com/emqx/emqx/pull/8758)
+
+## Bug fixes
+
+* Allow changing the license type from key to file (and vice-versa). [#8598](https://github.com/emqx/emqx/pull/8598)
+* Add back http connector config keys `max_retries` `retry_interval` as deprecated fields [#8672](https://github.com/emqx/emqx/issues/8672)
+  This caused upgrade failure in 5.0.4, because it would fail to boot on configs created from older version.
diff --git a/changes/v5.0.6-en.md b/changes/v5.0.6-en.md
new file mode 100644
index 000000000..342cb67e2
--- /dev/null
+++ b/changes/v5.0.6-en.md
@@ -0,0 +1,5 @@
+# v5.0.6
+
+## Bug fixes
+
+* Upgrade Dashboard version to fix an issue where the node status was not displayed correctly. [#8771](https://github.com/emqx/emqx/pull/8771)
diff --git a/changes/v5.0.7-en.md b/changes/v5.0.7-en.md
new file mode 100644
index 000000000..cfda78fb1
--- /dev/null
+++ b/changes/v5.0.7-en.md
@@ -0,0 +1,12 @@
+# v5.0.7
+
+## Enhancements
+
+* Do not auto-populate default SSL cipher suites, so that the configs are less bloated. [#8769](https://github.com/emqx/emqx/pull/8769)
+
+## Bug fixes
+
+* Remove `will_msg` (not used) field from the client API. [#8721](https://github.com/emqx/emqx/pull/8721)
+* Fix `$queue` topic name error in management API return. [#8728](https://github.com/emqx/emqx/pull/8728)
+* Fix race condition which may cause `client.connected` and `client.disconnected` out of order. [#8625](https://github.com/emqx/emqx/pull/8625)
+* Fix quic listener default idle timeout's type. [#8826](https://github.com/emqx/emqx/pull/8826)
diff --git a/changes/v5.0.8-en.md b/changes/v5.0.8-en.md
new file mode 100644
index 000000000..e05c3b89d
--- /dev/null
+++ b/changes/v5.0.8-en.md
@@ -0,0 +1,28 @@
+# v5.0.8
+
+## Enhancements
+
+* Print a warning message when boot with the default (insecure) Erlang cookie. [#8905](https://github.com/emqx/emqx/pull/8905)
+* Change the `/gateway` API path to plural form. [#8823](https://github.com/emqx/emqx/pull/8823)
+* Don't allow updating config items when they already exist in `local-override.conf`. [#8851](https://github.com/emqx/emqx/pull/8851)
+* Remove `node.etc_dir` from emqx.conf, because it is never used.
+  Also allow user to customize the logging directory [#8892](https://github.com/emqx/emqx/pull/8892)
+* Added a new API `POST /listeners` for creating listener. [#8876](https://github.com/emqx/emqx/pull/8876)
+* Close ExProto client process immediately if it's keepalive timeouted. [#8866](https://github.com/emqx/emqx/pull/8866)
+* Upgrade grpc-erl driver to 0.6.7 to support batch operation in sending stream. [#8866](https://github.com/emqx/emqx/pull/8866)
+
+
+## Bug fixes
+
+* Fix exhook `client.authorize` never being execauted. [#8780](https://github.com/emqx/emqx/pull/8780)
+* Fix JWT plugin don't support non-integer timestamp claims. [#8867](https://github.com/emqx/emqx/pull/8867)
+* Avoid publishing will message when client fails to auhtenticate. [#8887](https://github.com/emqx/emqx/pull/8887)
+* Speed up dispatching of shared subscription messages in a cluster [#8893](https://github.com/emqx/emqx/pull/8893)
+* Fix the extra / prefix when CoAP gateway parsing client topics. [#8658](https://github.com/emqx/emqx/pull/8658)
+* Speed up updating the configuration, When some nodes in the cluster are down. [#8857](https://github.com/emqx/emqx/pull/8857)
+* Fix delayed publish inaccurate caused by os time change. [#8926](https://github.com/emqx/emqx/pull/8926)
+* Fix that EMQX can't start when the retainer is disabled [#8911](https://github.com/emqx/emqx/pull/8911)
+* Fix that redis authn will deny the unknown users [#8934](https://github.com/emqx/emqx/pull/8934)
+* Fix ExProto UDP client keepalive checking error.
+  This causes the clients to not expire as long as a new UDP packet arrives [#8866](https://github.com/emqx/emqx/pull/8866)
+* Fix that MQTT Bridge message payload could be empty string. [#8949](https://github.com/emqx/emqx/pull/8949)
diff --git a/changes/v5.0.9-en.md b/changes/v5.0.9-en.md
new file mode 100644
index 000000000..c6d0b5192
--- /dev/null
+++ b/changes/v5.0.9-en.md
@@ -0,0 +1,34 @@
+# v5.0.9
+
+## Enhancements
+
+- Add `cert_common_name` and `cert_subject` placeholder support for authz_http and authz_mongo [#8973](https://github.com/emqx/emqx/pull/8973).
+
+- Use milliseconds internally in emqx_delayed to store the publish time, improving precision [#9060](https://github.com/emqx/emqx/pull/9060).
+
+- More rigorous checking of flapping to improve stability of the system [#9136](https://github.com/emqx/emqx/pull/9136).
+
+- No message(s) echo for the message publish APIs [#9155](https://github.com/emqx/emqx/pull/9155).
+  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.
+
+## Bug fixes
+
+- Check ACLs for last will testament topic before publishing the message [#8930](https://github.com/emqx/emqx/pull/8930).
+
+- Fix GET /listeners API crash when some nodes (in a cluster) is still loading the configs [#9002](https://github.com/emqx/emqx/pull/9002).
+
+- Fix empty variable interpolation in authentication and authorization [#8963](https://github.com/emqx/emqx/pull/8963).
+  Placeholders for undefined variables are rendered now as empty strings and do not cause errors anymore.
+
+- Fix the latency statistics error of the slow subscription stats [#8986](https://github.com/emqx/emqx/pull/8986).
+  Prior to this change when `stats_type` is `internal` or `response`, the begin time stamp was taken at wrong precision.
+
+- Fix shared subscription message re-dispatches [#9104](https://github.com/emqx/emqx/pull/9104).
+  - When discarding QoS 2 inflight messages, there were excessive logs
+  - For wildcard deliveries, the re-dispatch used the wrong topic (the publishing topic,
+    but not the subscribing topic), caused messages to be lost when dispatching.
+
+- Upgrade http client `gun` from 1.3.7 to [1.3.9](https://github.com/emqx/gun/tree/1.3.9)
+  Prior to this fix, long-lived HTTPS connections for HTTP auth or webhook integrations
+  may stall indefinitely, causing massive timeouts for HTTP requests.
diff --git a/changes/v5.0.9-zh.md b/changes/v5.0.9-zh.md
new file mode 100644
index 000000000..460d79941
--- /dev/null
+++ b/changes/v5.0.9-zh.md
@@ -0,0 +1,28 @@
+# v5.0.9
+
+## 增强
+
+- 为 `authz_http` 和 `authz_mongo` 增加了 `cert_common_name` 和 `cert_subject` 两个占位符 [#8973](https://github.com/emqx/emqx/pull/8973)。
+
+- 统一使用 Erlang 虚拟机的时间，而不是系统时间，可以避免系统时间修改后导致的延迟发布不准确问题 [#9060](https://github.com/emqx/emqx/pull/9060)。
+
+- 更严格的 flapping 检测，认证失败等也会进行计数 [#9136](https://github.com/emqx/emqx/pull/9136)。
+
+## 修复
+
+- 遗嘱消息发布前进行 ACL 检查 [#8930](https://github.com/emqx/emqx/pull/8930)。
+
+- 在集群环境下，当有节点还没有完全初始化好配置时，`GET /listeners` 可能会返回 HTTP 500 的错误 [#9002](https://github.com/emqx/emqx/pull/9002)。
+
+- 认证和鉴权的占位符替换中，如果没有找到匹配的值，使用空字符串代替，而不是抛出一异常 [#8963](https://github.com/emqx/emqx/pull/8963)。
+
+- 慢订阅统计中时间单位用错的问题 [#8986](https://github.com/emqx/emqx/pull/8986)。
+  当统计类型（`stats_type`）是 `internal` 或者 `response` 时，起始时间戳的精度使用错误。
+
+- 共享订阅消息重新派发 [#9104](https://github.com/emqx/emqx/pull/9104)。
+  - 当 QoS 2 的 inflight 消息被丢弃时，产生了大量的 warning 日志，修复后不再打印。
+  - 通配符订阅的共享订阅消息在重新派发时，使用了消息发布时的主题，而不是订阅的通配符主题选择
+    订阅组中的其他成员，导致转发失败。
+
+- HTTP 客户端 （`gun`） 从 1.3.7 升级到 [1.3.9](https://github.com/emqx/gun/tree/1.3.9)。
+  此次修复前，HTTP 认证和 webhook 等使用 HTTPS 客户端长连接的后端可能会进入一个无限等待状态，导致大量超时发生。

From 11daaa08e28992ae2d981c11d52643d48dffe022 Mon Sep 17 00:00:00 2001
From: "Zaiming (Stone) Shi" <zmstone@gmail.com>
Date: Mon, 24 Oct 2022 09:42:25 +0200
Subject: [PATCH 13/13] chore: bump version numbers to 5.0.9

---
 apps/emqx/include/emqx_release.hrl | 2 +-
 deploy/charts/emqx/Chart.yaml      | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/apps/emqx/include/emqx_release.hrl b/apps/emqx/include/emqx_release.hrl
index ad312e05d..caf70bf5a 100644
--- a/apps/emqx/include/emqx_release.hrl
+++ b/apps/emqx/include/emqx_release.hrl
@@ -32,7 +32,7 @@
 %% `apps/emqx/src/bpapi/README.md'
 
 %% Community edition
--define(EMQX_RELEASE_CE, "5.0.8").
+-define(EMQX_RELEASE_CE, "5.0.9").
 
 %% Enterprise edition
 -define(EMQX_RELEASE_EE, "5.0.0-alpha.1").
diff --git a/deploy/charts/emqx/Chart.yaml b/deploy/charts/emqx/Chart.yaml
index fa265e663..c46e95c9b 100644
--- a/deploy/charts/emqx/Chart.yaml
+++ b/deploy/charts/emqx/Chart.yaml
@@ -14,8 +14,8 @@ type: application
 
 # This is the chart version. This version number should be incremented each time you make changes
 # to the chart and its templates, including the app version.
-version: 5.0.8
+version: 5.0.9
 
 # This is the version number of the application being deployed. This version number should be
 # incremented each time you make changes to the application.
-appVersion: 5.0.8
+appVersion: 5.0.9