From c77837a9ea0983b74bb1f261f8b8d929fc7b4f14 Mon Sep 17 00:00:00 2001
From: William Yang <mscame@gmail.com>
Date: Mon, 15 Jan 2024 08:24:33 +0100
Subject: [PATCH] feat(quic): support reload with new binding port

---
 apps/emqx/rebar.config.script    |  2 +-
 apps/emqx/src/emqx_listeners.erl | 51 ++++++++++++++++++++++----------
 changes/feat-12325.en.md         |  1 +
 mix.exs                          |  2 +-
 rebar.config.erl                 |  2 +-
 5 files changed, 40 insertions(+), 18 deletions(-)
 create mode 100644 changes/feat-12325.en.md

diff --git a/apps/emqx/rebar.config.script b/apps/emqx/rebar.config.script
index 8c107d7e5..5f5ce18ba 100644
--- a/apps/emqx/rebar.config.script
+++ b/apps/emqx/rebar.config.script
@@ -24,7 +24,7 @@ IsQuicSupp = fun() ->
 end,
 
 Bcrypt = {bcrypt, {git, "https://github.com/emqx/erlang-bcrypt.git", {tag, "0.6.0"}}},
-Quicer = {quicer, {git, "https://github.com/emqx/quic.git", {tag, "0.0.311"}}}.
+Quicer = {quicer, {git, "https://github.com/emqx/quic.git", {tag, "0.0.312"}}}.
 
 Dialyzer = fun(Config) ->
     {dialyzer, OldDialyzerConfig} = lists:keyfind(dialyzer, 1, Config),
diff --git a/apps/emqx/src/emqx_listeners.erl b/apps/emqx/src/emqx_listeners.erl
index 74417f3b7..95815dacd 100644
--- a/apps/emqx/src/emqx_listeners.erl
+++ b/apps/emqx/src/emqx_listeners.erl
@@ -469,26 +469,23 @@ do_update_listener(Type, Name, OldConf, NewConf) when
     ok = ranch:set_protocol_options(Id, WsOpts),
     %% No-op if the listener was not suspended.
     ranch:resume_listener(Id);
-do_update_listener(quic = Type, Name, _OldConf, NewConf) ->
+do_update_listener(quic = Type, Name, OldConf, NewConf) ->
     case quicer:listener(listener_id(Type, Name)) of
         {ok, ListenerPid} ->
-            case quicer_listener:reload(ListenerPid, to_quicer_listener_opts(NewConf)) of
+            ListenOn = quic_listen_on(maps:get(bind, NewConf)),
+            case quicer_listener:reload(ListenerPid, ListenOn, to_quicer_listener_opts(NewConf)) of
                 ok ->
                     ok;
-                {error, _} = Error ->
-                    %% @TODO: prefer: case quicer_listener:reload(ListenerPid, to_quicer_listener_opts(OldConf)) of
-                    case quicer_listener:unlock(ListenerPid, 3000) of
+                Error ->
+                    case
+                        quic_listener_conf_rollback(
+                            ListenerPid, to_quicer_listener_opts(OldConf), Error
+                        )
+                    of
                         ok ->
-                            ?ELOG("Failed to reload QUIC listener ~p, but Rollback success\n", [
-                                Error
-                            ]),
                             {skip, Error};
-                        RestoreErr ->
-                            ?ELOG(
-                                "Failed to reload QUIC listener ~p, and Rollback failed as well\n",
-                                [Error]
-                            ),
-                            {error, {rollback_fail, RestoreErr}}
+                        E ->
+                            E
                     end
             end;
         E ->
@@ -991,7 +988,7 @@ quic_listen_on(Bind) ->
             Port
     end.
 
--spec to_quicer_listener_opts(map()) -> quicer:listener_opts().
+-spec to_quicer_listener_opts(map()) -> map().
 to_quicer_listener_opts(Opts) ->
     DefAcceptors = erlang:system_info(schedulers_online) * 8,
     SSLOpts = maps:from_list(ssl_opts(Opts)),
@@ -1018,3 +1015,27 @@ to_quicer_listener_opts(Opts) ->
     ),
     %% @NOTE: Optional options take precedence over required options
     maps:merge(Opts2, optional_quic_listener_opts(Opts)).
+
+-spec quic_listener_conf_rollback(
+    pid(),
+    map(),
+    Error :: {error, _, _} | {error, _}
+) -> ok | {error, any()}.
+quic_listener_conf_rollback(ListenerPid, #{bind := Bind} = Conf, Error) ->
+    ListenOn = quic_listen_on(Bind),
+    case quicer_listener:reload(ListenerPid, ListenOn, Conf) of
+        ok ->
+            ?ELOG(
+                "Failed to reload QUIC listener ~p, but Rollback success\n",
+                [
+                    Error
+                ]
+            ),
+            ok;
+        RestoreErr ->
+            ?ELOG(
+                "Failed to reload QUIC listener ~p, and Rollback failed as well\n",
+                [Error]
+            ),
+            {error, {rollback_fail, RestoreErr}}
+    end.
diff --git a/changes/feat-12325.en.md b/changes/feat-12325.en.md
new file mode 100644
index 000000000..cc5c5dd7e
--- /dev/null
+++ b/changes/feat-12325.en.md
@@ -0,0 +1 @@
+QUIC listener supports reload the listener binding without disrupting existing connections.
diff --git a/mix.exs b/mix.exs
index 5ef6fef36..7389cb0f9 100644
--- a/mix.exs
+++ b/mix.exs
@@ -795,7 +795,7 @@ defmodule EMQXUmbrella.MixProject do
   defp quicer_dep() do
     if enable_quicer?(),
       # in conflict with emqx and emqtt
-      do: [{:quicer, github: "emqx/quic", tag: "0.0.311", override: true}],
+      do: [{:quicer, github: "emqx/quic", tag: "0.0.312", override: true}],
       else: []
   end
 
diff --git a/rebar.config.erl b/rebar.config.erl
index e77b799f8..e374959dc 100644
--- a/rebar.config.erl
+++ b/rebar.config.erl
@@ -36,7 +36,7 @@ assert_otp() ->
     end.
 
 quicer() ->
-    {quicer, {git, "https://github.com/emqx/quic.git", {tag, "0.0.311"}}}.
+    {quicer, {git, "https://github.com/emqx/quic.git", {tag, "0.0.312"}}}.
 
 jq() ->
     {jq, {git, "https://github.com/emqx/jq", {tag, "v0.3.12"}}}.