node.js mysql依赖查询

Question

我正在学习node.js并遇到此问题，我进行了简单的登录以进行练习，当我尝试获取用户rol和rol的名称时，（在第二个查询中）我可以获取信息，但是看起来喜欢它仅在mysql查询范围内可用，我如何使其可用，以便我可以将所有这些信息发送回json响应？正确的做法是什么？

在这里我粘贴我的代码：

app.post('/auth', function(req, res) {
var username = req.body.username;
var password = req.body.password;
if (username && password) {
    var encryptedPass = sha1(password);
    dbConn.query('SELECT * FROM users WHERE username = ? AND password = ? and active="1"', [username, encryptedPass], function(error, results, fields) {
        if (results.length > 0) {
            var row = results[0];
            name = row.name+" "+row.lastname;
            id_user = row.id;
            var id_rol;
            var rol;

            dbConn.query('SELECT id_rol, name FROM users_roles INNER JOIN roles ON users_roles.id_user = roles.id and id_user="?"', [id_user], function(error, resultsRol, fields) {
                var rowRol = resultsRol[0];
                id_rol = rowRol['id_rol'];
                rol = rowRol['name'];
                console.log(id_rol, rol); // here it shows the result in the console
            });
            console.log(id_rol, rol);// here it shows the variables as undefined in the console

            req.session.loggedin = true;
            req.session.username = username;
            var token = jwt.sign({username:req.session.username},key);

            res.status(200).json({
                username:req.session.username,
                loggedin:1,
                token:token,
                name: name
            })

        } else {
            res.send('Incorrect Username and/or Password!');
            //res.redirect('/views/login.html');
        }           
        res.end();
    });
} else {
    res.send('Please enter Username and Password!');
    res.end();
}

}）;

谢谢！