From dc3e7dc21c07384b7c287d401e942c315a4c9632 Mon Sep 17 00:00:00 2001
From: Feng Lee <feng@emqx.io>
Date: Sat, 7 Dec 2019 16:45:20 +0800
Subject: [PATCH] Ignore the expired messages

---
 src/emqx_session.erl | 23 ++++++++++++++---------
 1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/src/emqx_session.erl b/src/emqx_session.erl
index a6917536a..107a539f3 100644
--- a/src/emqx_session.erl
+++ b/src/emqx_session.erl
@@ -400,9 +400,16 @@ dequeue(Cnt, Msgs, Q) ->
     case emqx_mqueue:out(Q) of
         {empty, _Q} -> dequeue(0, Msgs, Q);
         {{value, Msg = #message{qos = ?QOS_0}}, Q1} ->
-            dequeue(Cnt, [Msg|Msgs], Q1);
+            dequeue(Cnt, acc_msg(Msg, Msgs), Q1);
         {{value, Msg}, Q1} ->
-            dequeue(Cnt-1, [Msg|Msgs], Q1)
+            dequeue(Cnt-1, acc_msg(Msg, Msgs), Q1)
+    end.
+
+-compile({inline, [acc_msg/2]}).
+acc_msg(Msg, Msgs) ->
+    case emqx_message:is_expired(Msg) of
+        true  -> Msgs;
+        false -> [Msg|Msgs]
     end.
 
 %%--------------------------------------------------------------------
@@ -590,19 +597,17 @@ resume(ClientId, #session{subscriptions = Subs}) ->
 
 -spec(redeliver(session()) -> {ok, replies(), session()}).
 redeliver(Session = #session{inflight = Inflight}) ->
-    Pubs = replay(Inflight),
+    Pubs = lists:map(fun to_pub/1, emqx_inflight:to_list(Inflight)),
     case dequeue(Session) of
         {ok, NSession} -> {ok, Pubs, NSession};
         {ok, More, NSession} ->
             {ok, lists:append(Pubs, More), NSession}
     end.
 
-replay(Inflight) ->
-    lists:map(fun({PacketId, {pubrel, _Ts}}) ->
-                      {pubrel, PacketId};
-                 ({PacketId, {Msg, _Ts}}) ->
-                      {PacketId, emqx_message:set_flag(dup, true, Msg)}
-              end, emqx_inflight:to_list(Inflight)).
+to_pub({PacketId, {pubrel, _Ts}}) ->
+    {pubrel, PacketId};
+to_pub({PacketId, {Msg, _Ts}}) ->
+    {PacketId, emqx_message:set_flag(dup, true, Msg)}.
 
 %%--------------------------------------------------------------------
 %% Next Packet Id