vue-cli3.0 how mock data

mock data in vue-cli3.0

In the mock vue-cli3.0 data, data may be mock devServer the configuration item vue.config.js.

devServer: {
    before(app) {
      app.get('/api/seller', (req, res) => {
        res.json({
          errno: 0,
          data: seller
        })
      }),
        app.get('/api/goods', (req, res) => {
          res.json({
            errno: 0,
            data: goods
          })
        }),
        app.get('/api/ratings', (req, res) => {
          res.json({
            errno: 0,
            data: ratings
          })
        })
    }
  }