From 6fb9b6e517e0f35c9e1222dfb0292a6cbfb2c667 Mon Sep 17 00:00:00 2001
From: Thomas Posch <thomas.posch@dyves.com>
Date: Wed, 6 Apr 2022 11:24:03 +0200
Subject: [PATCH 1/2] Ignore SQLSTATE '45000' when RejectReadOnly is set

SQLSTATE '45000' is for user-defined exceptions.
Their errno can collide with system exceptions however.
Don't close the connection on user exceptions.
---
 packets.go | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/packets.go b/packets.go
index ab30601ae..fab7edba2 100644
--- a/packets.go
+++ b/packets.go
@@ -571,9 +571,19 @@ func (mc *mysqlConn) handleErrorPacket(data []byte) error {
 	// Error Number [16 bit uint]
 	errno := binary.LittleEndian.Uint16(data[1:3])
 
+	pos := 3
+
+	// SQL State [optional: # + 5bytes string]
+	var sqlstate string
+	if data[3] == 0x23 {
+		sqlstate = string(data[4 : 4+5])
+		pos = 9
+	}
+
 	// 1792: ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
 	// 1290: ER_OPTION_PREVENTS_STATEMENT (returned by Aurora during failover)
-	if (errno == 1792 || errno == 1290) && mc.cfg.RejectReadOnly {
+	// SQLSTATE 45000: user-defined exception
+	if (errno == 1792 || errno == 1290) && sqlstate != "45000" && mc.cfg.RejectReadOnly {
 		// Oops; we are connected to a read-only connection, and won't be able
 		// to issue any write statements. Since RejectReadOnly is configured,
 		// we throw away this connection hoping this one would have write
@@ -587,14 +597,6 @@ func (mc *mysqlConn) handleErrorPacket(data []byte) error {
 		return driver.ErrBadConn
 	}
 
-	pos := 3
-
-	// SQL State [optional: # + 5bytes string]
-	if data[3] == 0x23 {
-		//sqlstate := string(data[4 : 4+5])
-		pos = 9
-	}
-
 	// Error Message [string]
 	return &MySQLError{
 		Number:  errno,

From a0b5ef3778a7820d7a86afda24e5da7419399b9f Mon Sep 17 00:00:00 2001
From: Thomas Posch <thomas.posch@dyves.com>
Date: Wed, 6 Apr 2022 11:33:21 +0200
Subject: [PATCH 2/2] AUTHORS: add 'dyves labs AG'

---
 AUTHORS | 1 +
 1 file changed, 1 insertion(+)

diff --git a/AUTHORS b/AUTHORS
index 876b2964a..50b9593f0 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -110,6 +110,7 @@ Ziheng Lyu <zihenglv at gmail.com>
 Barracuda Networks, Inc.
 Counting Ltd.
 DigitalOcean Inc.
+dyves labs AG
 Facebook Inc.
 GitHub Inc.
 Google Inc.