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我正在尝试在 node-mysql 查询回调中访问 nodejs 服务器会话变量，但我似乎无法访问或设置 req.session 中的任何变量。

connection.connect();   
    connection.query('SELECT id, firstname, lastname FROM users WHERE username = ? AND password = ?', [username, password] , function(err, rows, fields) {
        if (err) throw err;
        console.log(rows.length);

        if(rows.length > 0){
            console.log('Firstname: ' + rows[0]['firstname'] + ' Last Name: ' + rows[0]['lastname']);
            req.session.firstname = rows[0]['firstname'];
            req.session.lastname = rows[0]['lastname'];
        } else {
            console.log('No Results');
        }
    }); 
    connection.end();

正如您在上面看到的，我正在尝试将名字和姓氏添加到会话中作为测试，以查看会话是否正常工作，但这最终将成为身份验证系统的一部分。

实现这一目标的最佳方法是什么。我错过了一些重要的中间件吗？

编辑：这是 routes.login_process 中的完整代码

var mysql = require('mysql');
var md5 = require('MD5');

exports.login_process = function(req, res){
    var username = req.body.username;
    var password = md5(req.body.password);

    var connection = mysql.createConnection({
        host     : 'localhost',
        user     : 'root',
        database : 'node',
        password : 'test',
    });

    connection.connect();   
    connection.query('SELECT id, firstname, lastname FROM users WHERE username = ? AND password = ?', [username, password] , function(err, rows, fields) {
        if (err) throw err;
        console.log(rows.length);

        if(rows.length > 0){
            console.log('Firstname: ' + rows[0]['firstname'] + ' Last Name: ' + rows[0]['lastname']);
            req.session.firstname = result[0]['firstname'];
            req.session.lastname = result[0]['lastname'];
        } else {
            console.log('No Results');
        }
    });
    connection.end();

    res.writeHead(200);
    res.end();
    //res.redirect('http://www.bbc.co.uk');
}

这是从发布到 /login 的表单发布的

app.post('/login', routes.login_process);
4

1 回答 1

1

The problem is that query is asynchronous, and your res.end() is occurring synchronously after the connection is initiated, thus ending the request before the query callback executes. After the response is ended, the request object can no longer be referenced. Change your code to:

connection.connect();   
connection.query('SELECT id, firstname, lastname FROM users WHERE username = ? AND password = ?', [username, password] , function(err, rows, fields) {
    if (err) throw err;
    console.log(rows.length);

    if(rows.length > 0){
        console.log('Firstname: ' + rows[0]['firstname'] + ' Last Name: ' + rows[0]['lastname']);
        req.session.firstname = result[0]['firstname'];
        req.session.lastname = result[0]['lastname'];
    } else {
        console.log('No Results');
    }

    res.writeHead(200);
    res.end();
});

connection.end();

This causes your response to wait until the query has completed.

Note that I am not sure where exactly the connection.end() will have to go. If it doesn't work where I put it, try moving it to where res.end() is (however this may or may not work depending on if the library you are using waits for existing queries before ending, or simply kills them)

于 2013-03-29T20:00:43.860 回答