From b69890ccd089cfad1c7aa70dde565be25a027735 Mon Sep 17 00:00:00 2001
From: wenyh <44251917+wenyh1@users.noreply.github.com>
Date: Fri, 25 Aug 2023 17:29:52 +0800
Subject: [PATCH] [inner-2340] fix: explain' lost connection....

(cherry picked from commit 2b87829dc786e4644c4ee67bf842a94a887ec04f)
---
 .../dble/server/handler/ExplainHandler.java   | 31 ++++++++++++-------
 1 file changed, 20 insertions(+), 11 deletions(-)

diff --git a/src/main/java/com/actiontech/dble/server/handler/ExplainHandler.java b/src/main/java/com/actiontech/dble/server/handler/ExplainHandler.java
index e3be560085..c1524081ba 100644
--- a/src/main/java/com/actiontech/dble/server/handler/ExplainHandler.java
+++ b/src/main/java/com/actiontech/dble/server/handler/ExplainHandler.java
@@ -48,6 +48,7 @@
 import java.sql.SQLException;
 import java.sql.SQLNonTransientException;
 import java.sql.SQLSyntaxErrorException;
+import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
 
@@ -243,6 +244,7 @@ private static RouteResultsetNode getTryRouteSingleNode(BaseHandlerBuilder build
     }
 
     public static void writeOutHeadAndEof(ShardingService service, RouteResultset rrs) {
+        final List<RowDataPacket> rows = getRows(service, rrs);
         ByteBuffer buffer = service.allocate();
         // writeDirectly header
         ResultSetHeaderPacket header = PacketUtil.getHeader(FIELD_COUNT);
@@ -260,20 +262,30 @@ public static void writeOutHeadAndEof(ShardingService service, RouteResultset rr
         eof.setPacketId(service.nextPacketId());
         buffer = eof.write(buffer, service, true);
 
+        // writeDirectly rows
+        for (RowDataPacket row : rows) {
+            row.setPacketId(service.nextPacketId());
+            buffer = row.write(buffer, service, true);
+        }
+
+        // writeDirectly last eof
+        EOFRowPacket lastEof = new EOFRowPacket();
+        lastEof.setPacketId(service.nextPacketId());
+        lastEof.write(buffer, service);
+    }
+
+    private static List<RowDataPacket> getRows(ShardingService service, RouteResultset rrs) {
+        LinkedList<RowDataPacket> rows = new LinkedList<>();
         if (!rrs.isNeedOptimizer()) {
             // writeDirectly rows
             for (RouteResultsetNode node : rrs.getNodes()) {
-                RowDataPacket row = getRow(node, service.getCharset().getResults());
-                row.setPacketId(service.nextPacketId());
-                buffer = row.write(buffer, service, true);
+                rows.add(getRow(node, service.getCharset().getResults()));
             }
         } else {
             BaseHandlerBuilder builder = buildNodes(rrs, service);
             RouteResultsetNode routeSingleNode = getTryRouteSingleNode(builder, rrs);
             if (routeSingleNode != null) {
-                RowDataPacket row = getRow(routeSingleNode, service.getCharset().getResults());
-                row.setPacketId(service.nextPacketId());
-                buffer = row.write(buffer, service, true);
+                rows.add(getRow(routeSingleNode, service.getCharset().getResults()));
             } else {
                 List<ReferenceHandlerInfo> results = ComplexQueryPlanUtil.getComplexQueryResult(builder);
                 for (ReferenceHandlerInfo result : results) {
@@ -282,13 +294,10 @@ public static void writeOutHeadAndEof(ShardingService service, RouteResultset rr
                     row.add(StringUtil.encode(result.getType(), service.getCharset().getResults()));
                     row.add(StringUtil.encode(result.getRefOrSQL(), service.getCharset().getResults()));
                     row.setPacketId(service.nextPacketId());
-                    buffer = row.write(buffer, service, true);
+                    rows.add(row);
                 }
             }
         }
-        // writeDirectly last eof
-        EOFRowPacket lastEof = new EOFRowPacket();
-        lastEof.setPacketId(service.nextPacketId());
-        lastEof.write(buffer, service);
+        return rows;
     }
 }