Question

根据Node MySQL文档（https://github.com/mysqljs/mysql#introduction）：

Every method you invoke on a connection is queued and executed in sequence.

和

Closing the connection is done using end() which makes sure all remaining queries are executed before sending a quit packet to the mysql server.

然而，下面的代码不起作用，因为在SQL查询可以运行之前调用connection.end()方法。如果我注释掉connection.end()行，它会起作用，但是脚本在完成时会挂起（不会关闭/结束），要求我按ctrl-c结束它。

如果我将MySQL connection对象和connection.end()调用移动到lineReader.createInterface().on()块，它可以正常工作 - 脚本正确终止...但它正在创建一个新连接对于每个INSERT语句。

每次关闭和重新连接似乎都是正确的。我误解了Node MySQL文档吗？还有更好的方法吗？

let lineReader  = require('readline');
let file        = require('fs');
let mysql       = require('mysql');

let connection  = mysql.createConnection({
    host: '127.0.0.1',
    port: 33060,
    user: 'homestead',
    password: 'secret',
    database: 'sentinel',
});

lineReader.createInterface({
        input: file.createReadStream('proxies/proxies.txt')
    }).on('line', function (line) {
        let ary = line.split(/[:, ]/);
        let insert_sql;

        if (typeof ary[2] !== 'undefined' && typeof  ary[3] !== 'undefined') {
            insert_sql =
                'INSERT INTO proxies (host, port, username, password) ' +
                'VALUES ("' + ary[0] + '", "' + ary[1] + '", "' + ary[2] + '", "' + ary[3] + '")';
        } else {
            insert_sql =
                'INSERT INTO proxies (host, port) ' +
                'VALUES ("' + ary[0] + '", "' + ary[1] + '")';
        }

        connection.query(insert_sql, function (error, results, fields) {
            if (error) {
                console.log('error: ' + error);
            } else {
                console.log('success: ' + insert_sql);
            }
        });

    });

connection.end();

Answer 1

您可以在connection.end()事件监听器中调用close：

lineReader.createInterface({
        input: file.createReadStream('proxies/proxies.txt')
    }).on('line', function (line) {
      ...
    }).on('close', function() {
      connection.end();
    });

调用quit后无法将Query排入队列

1 个答案: