From af574d17d5d8868ecb2b1e8bfce1b1e1d4ce25a6 Mon Sep 17 00:00:00 2001
From: xige-16 <xi.ge@zilliz.com>
Date: Sat, 28 Aug 2021 12:51:57 +0800
Subject: [PATCH] Fix querycoord panic when stop nil conn of querynoClient
 (#7346)

Signed-off-by: xige-16 <xi.ge@zilliz.com>
---
 internal/distributed/querynode/client/client.go   |  6 +++++-
 .../distributed/querynode/client/client_test.go   | 15 +++++++++++++++
 2 files changed, 20 insertions(+), 1 deletion(-)
 create mode 100644 internal/distributed/querynode/client/client_test.go

diff --git a/internal/distributed/querynode/client/client.go b/internal/distributed/querynode/client/client.go
index ee24b2e995..9cabe4e337 100644
--- a/internal/distributed/querynode/client/client.go
+++ b/internal/distributed/querynode/client/client.go
@@ -127,7 +127,11 @@ func (c *Client) Start() error {
 }
 
 func (c *Client) Stop() error {
-	return c.conn.Close()
+	c.cancel()
+	if c.conn != nil {
+		c.conn.Close()
+	}
+	return nil
 }
 
 // Register dummy
diff --git a/internal/distributed/querynode/client/client_test.go b/internal/distributed/querynode/client/client_test.go
new file mode 100644
index 0000000000..a1a526bc77
--- /dev/null
+++ b/internal/distributed/querynode/client/client_test.go
@@ -0,0 +1,15 @@
+package grpcquerynodeclient
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNilClient(t *testing.T) {
+	client, err := NewClient(context.Background(), "test")
+	assert.Nil(t, err)
+	err = client.Stop()
+	assert.Nil(t, err)
+}