Backend 2

router模块化思想

上节课backend_class_1根据features创建了不同的role. 其中回调函数async function要提取出放到新文件夹Controllers中.

课上代码

backend根目录下index.js (可以用server.js避免歧义)

//npm init
//npm i express cors axios json-server
//npm i nodemon -D
//npm run json:server
//npm run server (npm nodemon index.js)在package.json script里面修改

const express = require("express");
const cors = require("cors");
const router = require("./routes/index");
const { handleErrors } = require("./middleware/errorMiddleware");
const app = express();

app.use(cors()); // 解决跨域问题
app.use(express.json()); //允许解析使用json数据

//router需要挂在在数据解析(json)和跨域全局中间件(cors)后面
app.use("/api", router); // 提取公共部分, 这样每个路由不需要重复写"/api"

// use error middleware at the end (全局中间件)
app.use(handleErrors);

const PORT = 80;
app.listen(PORT, function () {
    console.log("Server is running on http://localhost:80");
});

//app.use(express.json())// parse JSON requests
//app.use(express.urlencoded({extended:true})) //parse URL-encoded requests
//app.use(cors()) //必须在路由之前挂在，解决跨域问题
//app.use(authMiddleware);// custom authentication middleare 比如用户验证，api授权之类的
//app.use(routes) // route handlers
//app.use(handleErrors) // error handling middleware (at the end) error中间件在路由后挂载