数据库服务限时秒杀

const express = require('express');
const mysql = require('mysql');
const app = express();

// 创建数据库连接池
const pool = mysql.createPool({
  host: 'localhost',
  user: 'root',
  password: 'password',
  database: 'test',
  connectionLimit: 10
});

app.get('/seckill', (req, res) => {
  const { productId, userId } = req.query;

  pool.getConnection((err, connection) => {
    if (err) throw err;

    // 开启事务
    connection.beginTransaction(err => {
      if (err) {
        connection.release();
        return res.status(500).send('Transaction failed');
      }

      // 检查库存
      connection.query('SELECT stock FROM products WHERE id = ?', [productId], (err, results) => {
        if (err) {
          return connection.rollback(() => {
            connection.release();
            res.status(500).send('Database error');
          });
        }

        const stock = results[0].stock;
        if (stock <= 0) {
          return connection.rollback(() => {
            connection.release();
            res.status(400).send('Out of stock');
          });
        }

        // 更新库存并记录订单
        connection.query('UPDATE products SET stock = stock - 1 WHERE id = ?', [productId], (err, result) => {
          if (err) {
            return connection.rollback(() => {
              connection.release();
              res.status(500).send('Update failed');
            });
          }

          connection.query('INSERT INTO orders (product_id, user_id) VALUES (?, ?)', [productId, userId], (err, result) => {
            if (err) {
              return connection.rollback(() => {
                connection.release();
                res.status(500).send('Insert failed');
              });
            }

            // 提交事务
            connection.commit(err => {
              if (err) {
                return connection.rollback(() => {
                  connection.release();
                  res.status(500).send('Commit failed');
                });
              }
              connection.release();
              res.status(200).send('Seckill successful');
            });
          });
        });
      });
    });
  });
});

app.listen(3000, () => console.log('Server running on port 3000'));