From e7d70c142c4bb9fa02e596e939317c0cf37515e0 Mon Sep 17 00:00:00 2001
From: ieQu1 <99872536+ieQu1@users.noreply.github.com>
Date: Tue, 24 May 2022 13:03:18 +0200
Subject: [PATCH] fix(emqx_shared_sub): Don't crash on table schema change

---
 apps/emqx/src/emqx_shared_sub.erl | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/apps/emqx/src/emqx_shared_sub.erl b/apps/emqx/src/emqx_shared_sub.erl
index ee45b991d..5539c4427 100644
--- a/apps/emqx/src/emqx_shared_sub.erl
+++ b/apps/emqx/src/emqx_shared_sub.erl
@@ -354,8 +354,10 @@ handle_cast(Msg, State) ->
     ?SLOG(error, #{msg => "unexpected_cast", req => Msg}),
     {noreply, State}.
 
-handle_info({mnesia_table_event, {write, NewRecord, _}}, State = #state{pmon = PMon}) ->
-    #emqx_shared_subscription{subpid = SubPid} = NewRecord,
+handle_info(
+    {mnesia_table_event, {write, #emqx_shared_subscription{subpid = SubPid}, _}},
+    State = #state{pmon = PMon}
+) ->
     {noreply, update_stats(State#state{pmon = emqx_pmon:monitor(SubPid, PMon)})};
 %% The subscriber may have subscribed multiple topics, so we need to keep monitoring the PID until
 %% it `unsubscribed` the last topic.