如果资源不存在，我的API应该使用什么HTTP代码

const express = require('express');
const app = express();
const port = 3000;

app.get('/resource/:id', (req, res) => {
  const resourceId = req.params.id;
  // 假设我们有一个资源列表
  const resources = ['resource1', 'resource2', 'resource3'];

  if (!resources.includes(resourceId)) {
    return res.status(404).json({ message: 'Resource not found' });
  }

  res.json({ message: `Resource ${resourceId} found` });
});

app.listen(port, () => {
  console.log(`Server running at http://localhost:${port}`);
});