From dbdfec349475255185ae409320a8e027167cee6e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Javier=20Jaramago=20Fern=C3=A1ndez?=
 <jaramago.fernandez.javier@gmail.com>
Date: Sat, 13 Aug 2022 09:02:53 +0200
Subject: [PATCH] Add 'ASYNC_IDLE' precondition for connections considered for
 expiring

If any scenario is found in which we may want to consider a non
'ASYNC_IDLE' connection for expiring, this precondition shall be
removed, and checks should be responsible for ensuring 'ASYNC_IDLE'
state in the connection.
---
 lib/MySQL_Session.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/MySQL_Session.cpp b/lib/MySQL_Session.cpp
index fd0b1de22..a33860ed6 100644
--- a/lib/MySQL_Session.cpp
+++ b/lib/MySQL_Session.cpp
@@ -697,9 +697,10 @@ void MySQL_Session::update_expired_conns(const vector<function<bool(MySQL_Connec
 		if (myconn != nullptr) {
 			const bool is_active_transaction = myconn->IsActiveTransaction();
 			const bool multiplex_disabled = myconn->MultiplexDisabled(false);
+			const bool is_idle = myconn->async_state_machine == ASYNC_IDLE;
 
 			// Make sure the connection is reusable before performing any check
-			if (myconn->reusable==true && is_active_transaction==false && multiplex_disabled==false) {
+			if (myconn->reusable==true && is_active_transaction==false && multiplex_disabled==false && is_idle) {
 				for (const function<bool(MySQL_Connection*)>& check : checks) {
 					if (check(myconn)) {
 						this->hgs_expired_conns.push_back(mybe->hostgroup_id);