创建并连接数据库，并修改登录和注册接口

node_modules/mysql2/lib/create_connection.js

@@ -0,0 +1,10 @@
+'use strict';
+
+const Connection = require('./connection.js');
+const ConnectionConfig = require('./connection_config.js');
+
+function createConnection(opts) {
+  return new Connection({ config: new ConnectionConfig(opts) });
+}
+
+module.exports = createConnection;