创建并连接数据库，并修改登录和注册接口

node_modules/mysql2/lib/create_pool.js

@@ -0,0 +1,10 @@
+'use strict';
+
+const Pool = require('./pool.js');
+const PoolConfig = require('./pool_config.js');
+
+function createPool(config) {
+  return new Pool({ config: new PoolConfig(config) });
+}
+
+module.exports = createPool;