From c8fa957dbd39c4a588268691cba2d5ae52fe84b2 Mon Sep 17 00:00:00 2001
From: KomachiSion <xiweng.yy@alibaba-inc.com>
Date: Mon, 26 Sep 2022 14:49:40 +0800
Subject: [PATCH] For #8611, Close old datasource connection.

---
 .../ExternalDataSourceServiceImpl.java        | 27 ++++++++++++++++---
 1 file changed, 24 insertions(+), 3 deletions(-)

diff --git a/config/src/main/java/com/alibaba/nacos/config/server/service/datasource/ExternalDataSourceServiceImpl.java b/config/src/main/java/com/alibaba/nacos/config/server/service/datasource/ExternalDataSourceServiceImpl.java
index 8ac97a99f56..ad31e6e3b55 100644
--- a/config/src/main/java/com/alibaba/nacos/config/server/service/datasource/ExternalDataSourceServiceImpl.java
+++ b/config/src/main/java/com/alibaba/nacos/config/server/service/datasource/ExternalDataSourceServiceImpl.java
@@ -119,16 +119,37 @@ public void init() {
     @Override
     public synchronized void reload() throws IOException {
         try {
-            dataSourceList = new ExternalDataSourceProperties()
+            final List<JdbcTemplate> testJtListNew = new ArrayList<JdbcTemplate>();
+            final List<Boolean> isHealthListNew = new ArrayList<Boolean>();
+    
+            List<HikariDataSource> dataSourceListNew = new ExternalDataSourceProperties()
                     .build(EnvUtil.getEnvironment(), (dataSource) -> {
                         JdbcTemplate jdbcTemplate = new JdbcTemplate();
                         jdbcTemplate.setQueryTimeout(queryTimeout);
                         jdbcTemplate.setDataSource(dataSource);
-                        testJtList.add(jdbcTemplate);
-                        isHealthList.add(Boolean.TRUE);
+                        testJtListNew.add(jdbcTemplate);
+                        isHealthListNew.add(Boolean.TRUE);
                     });
+    
+            final List<HikariDataSource> dataSourceListOld = dataSourceList;
+            final List<JdbcTemplate> testJtListOld = testJtList;
+            dataSourceList = dataSourceListNew;
+            testJtList = testJtListNew;
+            isHealthList = isHealthListNew;
             new SelectMasterTask().run();
             new CheckDbHealthTask().run();
+            
+            //close old datasource.
+            if (dataSourceListOld != null && !dataSourceListOld.isEmpty()) {
+                for (HikariDataSource dataSource : dataSourceListOld) {
+                    dataSource.close();
+                }
+            }
+            if (testJtListOld != null && !testJtListOld.isEmpty()) {
+                for (JdbcTemplate oldJdbc : testJtListOld) {
+                    oldJdbc.setDataSource(null);
+                }
+            }
         } catch (RuntimeException e) {
             FATAL_LOG.error(DB_LOAD_ERROR_MSG, e);
             throw new IOException(e);