🐛fix a bug

cron_task/offline_monitoring.go

@@ -41,7 +41,7 @@ func offlineMonitoring() {
 			isOnline := time.Since(p.LastHandshakeTime).Minutes() < 3
 
 			// 未离线
-			if !isOnline {
+			if isOnline {
 				continue
 			}
 
@@ -51,7 +51,7 @@ func offlineMonitoring() {
 			content += fmt.Sprintf("最后握手时间：%s\r\n", p.LastHandshakeTime.Format("2006-01-02 15:04:05"))
 
 			// 离线并且配置了邮箱，准备发送邮件
-			err = utils.Mail().SendMail(clientInfo.Email, fmt.Sprintf("客户端离线通知"), content, "")
+			err = utils.Mail().SendMail(clientInfo.Email, fmt.Sprintf("客户端[%s]离线通知", clientInfo.Name), content, "")
 			if err != nil {
 				log.Errorf("发送离线通知邮件失败: %v", err.Error())
 				continue