360星计划-node.js的web开发_360浏览器编写node.js-优快云博客

本文链接：https://blog.youkuaiyun.com/violet_seven/article/details/105444099

1、http模块

const http = require('http');
const server = http.createServer((req, res) => {
  res.end('Hello World');
});
server.listen(3000);

使用http模块来进行web开发

http.createServer：
- req表示用户请求体
- res表示请求响应体
- 
使用server.listen方法进行监听

2、koa模块

const Koa = require('koa');
const app = new Koa();

// response
app.use(ctx => {
  ctx.body = 'Hello Koa';
});

app.listen(3000);

koa独有use方法会对中间件进行挂载

//koa的部分源码

module.exports = class Application extends Emitter {
  ...
  
  listen() {
    debug('listen');
    const server = http.createServer(this.callback());
    return server.listen.apply(server, arguments);
  }

  use(fn) {
    this.middleware.push(fn);
    return this;
  }//将fn挂载到middleware
  
  callback() {
    const fn = compose(this.middleware);
    
    if (!this.listeners('error').length) this.on('error', this.onerror);

    const handleRequest = (req, res) => {
      res.statusCode = 404;
      const ctx = this.createContext(req, res);
      const onerror = err => ctx.onerror(err);
      const handleResponse = () => respond(ctx);
      onFinished(res, onerror);
      return fn(ctx).then(handleResponse).catch(onerror);
    };

    return handleRequest;
  }
  //createContest方法挂载request和response
  createContext(req, res) {
    const context = Object.create(this.context);
    const request = context.request = Object.create(this.request);
    const response = context.response = Object.create(this.response);
    context.app = request.app = response.app = this;
    context.req = request.req = response.req = req;
    context.res = request.res = response.res = res;
    request.ctx = response.ctx = context;
    request.response = response;
    response.request = request;
    context.originalUrl = request.originalUrl = req.url;
    context.cookies = new Cookies(req, res, {
      keys: this.keys,
      secure: request.secure
    });
    request.ip = request.ips[0] || req.socket.remoteAddress || '';
    context.accept = request.accept = accepts(req);
    context.state = {};
    return context;
  }
}

koa缺少：

逻辑分层
路由处理
数据解析、校验
权限校验
Session、Cache
数据库、Redis
安全
…

缺点：

Koa 无规范约束，不利于团队开发
中间件繁多，质量参差不齐，选择困难

3、THINKJS

安装：npm install -g think-cli
thinkjs
优势：做了企业级目录式的规划

src目录存放项目源码
- bootstrap目录存放用户启动执行脚本
- config目录存放项目配置文件
  - adapter存放数据库、日志等配置
- controller存放访问路由逻辑
- logic存放用户参数校验、权限校验逻辑
- model存放项目会使用到的数据库操作
view存放项目的模板文件
www存放项目的静态资源
development.js：项目开发环境的启动文件
production.js：项目生产环境的启动文件

// src/controller/index.js
export default class extends think.Controller {
  indexAction() {
    return this.display();
  }
}

// view/index_index.html
<h3>Hello World</h3>