node express简单搭建服务器

//1. 引入express
const express = require('express');

//2. 创建应用对象
const app = express();

//3. 创建路由规则
// request 是对请求报文的封装
// response 是对响应报文的封装
app.get('/server', (request, response) => {
    //设置响应头  设置允许跨域
    response.setHeader('Access-Control-Allow-Origin', '*');
    //设置响应体
    response.send('HELLO AJAX - 2');
});

//可以接收任意类型的请求 
app.all('/server', (request, response) => {
    //设置响应头  设置允许跨域
    response.setHeader('Access-Control-Allow-Origin', '*');
    //响应头
    response.setHeader('Access-Control-Allow-Headers', '*');
    //设置响应体
    response.send('HELLO AJAX POST');
});

//JSON 响应
app.all('/json-server', (request, response) => {
    //设置响应头  设置允许跨域
    response.setHeader('Access-Control-Allow-Origin', '*');
    //响应头
    response.setHeader('Access-Control-Allow-Headers', '*');
    //响应一个数据
    const data = {
        name: '钢铁侠'
    };
    //对对象进行字符串转换
    let str = JSON.stringify(data);
    //设置响应体
    response.send(str);
});

//针对 IE 缓存
app.get('/ie', (request, response) => {
    //设置响应头  设置允许跨域
    response.setHeader('Access-Control-Allow-Origin', '*');
    //设置响应体
    response.send('HELLO IE - 5');
});

//延时响应
app.all('/delay', (request, response) => {
    //设置响应头  设置允许跨域
    response.setHeader('Access-Control-Allow-Origin', '*');
    response.setHeader('Access-Control-Allow-Headers', '*');
    setTimeout(() => {
        //设置响应体
        response.send('延时响应');
    }, 1000)
});

//jQuery 服务
app.all('/jquery-server', (request, response) => {
    //设置响应头  设置允许跨域
    response.setHeader('Access-Control-Allow-Origin', '*');
    response.setHeader('Access-Control-Allow-Headers', '*');
    // response.send('Hello jQuery AJAX');
    const data = {name:'钢铁侠'};
    response.send(JSON.stringify(data));
});

//axios 服务
app.all('/axios-server', (request, response) => {
    //设置响应头  设置允许跨域
    response.setHeader('Access-Control-Allow-Origin', '*');
    response.setHeader('Access-Control-Allow-Headers', '*');
    // response.send('Hello jQuery AJAX');
    const data = {name:'钢铁侠'};
    response.send(JSON.stringify(data));
});

//fetch 服务
app.all('/fetch-server', (request, response) => {
    //设置响应头  设置允许跨域
    response.setHeader('Access-Control-Allow-Origin', '*');
    response.setHeader('Access-Control-Allow-Headers', '*');
    // response.send('Hello jQuery AJAX');
    const data = {name:'钢铁侠'};
    response.send(JSON.stringify(data));
});

//jsonp服务
app.all('/jsonp-server',(request, response) => {
    // response.send('console.log("hello jsonp")');
    const data = {
        name: '钢铁侠'
    };
    //将数据转化为字符串
    let str = JSON.stringify(data);
    //返回结果
    response.end(`handle(${str})`);
});

//用户名检测是否存在
app.all('/check-username',(request, response) => {
    // response.send('console.log("hello jsonp")');
    const data = {
        exist: 1,
        msg: '用户名已经存在'
    };
    //将数据转化为字符串
    let str = JSON.stringify(data);
    //返回结果
    response.end(`handle(${str})`);
});

//
app.all('/jquery-jsonp-server',(request, response) => {
    // response.send('console.log("hello jsonp")');
    const data = {
        name:'前端程序员',
        city: ['北京','上海','深圳']
    };
    //将数据转化为字符串
    let str = JSON.stringify(data);
    //接收 callback 参数
    let cb = request.query.callback;

    //返回结果
    response.end(`${cb}(${str})`);
});

app.all('/cors-server', (request, response)=>{
    //设置响应头
    response.setHeader("Access-Control-Allow-Origin", "*");
    response.setHeader("Access-Control-Allow-Headers", '*');
    response.setHeader("Access-Control-Allow-Method", '*');
    // response.setHeader("Access-Control-Allow-Origin", "http://127.0.0.1:5500");
    response.send('hello CORS');
});

//4. 监听端口启动服务
app.listen(8000, () => {
    console.log("服务已经启动, 8000 端口监听中....");
});