Close idle connections in influxdb outputs when reloading (#5912)

plugins/outputs/influxdb/http.go

@@ -448,3 +448,7 @@ func makeQueryURL(loc *url.URL) (string, error) {
 	}
 	return u.String(), nil
 }
+
+func (c *httpClient) Close() {
+	internal.CloseIdleConnections(c.client)
+}

plugins/outputs/influxdb/influxdb.go

@@ -27,6 +27,7 @@ type Client interface {
 	CreateDatabase(ctx context.Context, database string) error
 	Database() string
 	URL() string
+	Close()
 }
 
 // InfluxDB struct is the primary data structure for the plugin
@@ -183,6 +184,9 @@ func (i *InfluxDB) Connect() error {
 }
 
 func (i *InfluxDB) Close() error {
+	for _, client := range i.clients {
+		client.Close()
+	}
 	return nil
 }
 

plugins/outputs/influxdb/influxdb_test.go

@@ -19,6 +19,7 @@ type MockClient struct {
 	WriteF          func(context.Context, []telegraf.Metric) error
 	CreateDatabaseF func(ctx context.Context, database string) error
 	DatabaseF       func() string
+	CloseF          func()
 }
 
 func (c *MockClient) URL() string {
@@ -37,6 +38,10 @@ func (c *MockClient) Database() string {
 	return c.DatabaseF()
 }
 
+func (c *MockClient) Close() {
+	c.CloseF()
+}
+
 func TestDeprecatedURLSupport(t *testing.T) {
 	var actual *influxdb.UDPConfig
 	output := influxdb.InfluxDB{

plugins/outputs/influxdb/udp.go

@@ -136,3 +136,6 @@ func scanLines(data []byte, atEOF bool) (advance int, token []byte, err error) {
 	}
 	return 0, nil, nil
 }
+
+func (c *udpClient) Close() {
+}