关于node.js:使用express连接http

const express = require("express");
 
// 创立http实例
const app = express();
 
app.use((req,res,next) => {
   console.log('申请开始...', req.method,req.url);
   next(); 
})
 
app.use((req,res,next) => {
   req.cookie = {
     userId: 'aaa111'
   }
   next()
})
 
app.use('/api', (req,res,next) => {
   console.log('解决/api路由');
   next();
})
app.get('/api', (req,res,next) => {
   console.log('get解决/api路由');
   next();
})
app.post('/api', (req,res,next) => {
   console.log('post解决/api路由');
   next();
});
 
app.use((req, res, next) => {
    console.log('解决 404')
    res.json({
        errno: -1,
        msg: '404 not fount'
    })
})
 
app.listen(3000, () => {
    console.log('server is running on port 3000')
})