text: const koaError = require('koa-error')
  const path = require('path')
  /**
   * 404 error处理
   */
  
  module.exports = () => {
    return koaError({
      engine: 'nunjucks',
      template: path.join(__dirname, '../views/error/index.html'),
      accepts: ['html']
    })
  }
  