From ad9fc41319a97a17a16be25a3bcdd9e309afac72 Mon Sep 17 00:00:00 2001
From: jchrys <jchrys@me.com>
Date: Thu, 8 Feb 2024 01:36:53 +0900
Subject: [PATCH] Fixed NPE with `SslMode.TUNNEL` Usage

Motivation:
A NPE was identified when utilizing `SslMode.TUNNEL`, introduced by PR #204. The issue arises when `ConnectionContext#isMariaDb` is invoked from `SslBridgeHandler#isTls13Enabled`, leading to an NPE due to the ConnectionContext not being initialized at that time.

Modification:
We have updated ConnectionContext#isMariaDb to return false if the context has not been initialized, preventing the NPE. (Mainly to restore previous behavior)

Result:
This change addresses the NPE issue, ensuring stability when `SslMode.TUNNEL` is selected. It resolves the problem reported in https://github.com/GoogleCloudPlatform/cloud-sql-jdbc-socket-factory/pull/1828
---
 src/main/java/io/asyncer/r2dbc/mysql/ConnectionContext.java | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/main/java/io/asyncer/r2dbc/mysql/ConnectionContext.java b/src/main/java/io/asyncer/r2dbc/mysql/ConnectionContext.java
index 3039ea19b..a1735caa8 100644
--- a/src/main/java/io/asyncer/r2dbc/mysql/ConnectionContext.java
+++ b/src/main/java/io/asyncer/r2dbc/mysql/ConnectionContext.java
@@ -57,6 +57,7 @@ public final class ConnectionContext implements CodecContext {
      */
     private volatile short serverStatuses = ServerStatuses.AUTO_COMMIT;
 
+    @Nullable
     private volatile Capability capability = null;
 
     ConnectionContext(ZeroDateOption zeroDateOption, @Nullable Path localInfilePath,
@@ -109,7 +110,8 @@ public ZoneId getServerZoneId() {
 
     @Override
     public boolean isMariaDb() {
-        return capability.isMariaDb() || serverVersion.isMariaDb();
+        final Capability c = capability;
+        return c != null && (c.isMariaDb() || serverVersion.isMariaDb());
     }
 
     boolean shouldSetServerZoneId() {