text: 
  const Koa = require('koa');
  const Router = require('./index');
  const app = new Koa();
  const router = new Router();
  
  router.get('/index', async ctx => { ctx.body = 'index page'; });
  router.get('/post', async ctx => { ctx.body = 'post page'; });
  router.get('/list', async ctx => { ctx.body = 'list page'; });
  router.get('/item', async ctx => { ctx.body = 'item page'; });
  
  app.use(router.routes());
  
  app.use(async ctx => {
    ctx.body = '404';
  });
  
  app.listen(3000);
  console.log('listening on port 3000');
  