## 1. 静态资源服务器命令行工具

  1. 创建一个服务器
  2. 实现压缩
  3. 实现缓存
  4. 实现断点续传
  5. 发布命令行工具

静态资源服务器

1.1 -r/--range #

2. 多语言切换 #

可以通过Accept-Language检测浏览器的语言

let http = require('http');
let pack = {
    en: {
        title: 'hello'
    },
    cn: {
        title: '欢迎'
    }
}

function request(req, res) {
    let acceptLangulage = req.headers['accept-language'];
    let lan = 'en';
    if (acceptLangulage) {
        lan = acceptLangulage.split(',').map(item => {
            let values = item.split(';');
            return {
                name: values[0].split('-')[0],
                q: isNaN(values[1]) ? 1 : parseInt(values[1])
            }
        }).sort((lan1, lan2) => lan1.q - lan2.q).shift().name;
    }
    res.end(pack[lan] ? pack[lan].title : pack['en'].title);

}
let server = http.createServer();
server.on('request', request);
server.listen(8080);

3. 图片防盗链 # 

let http = require('http');
let url = require('url');
let path = require('path');
let fs = require('fs');
let root = path.join(__dirname, 'public');

function removePort(host) {
    return host.split(':')[0]
}

function getHostName(urlAddr) {
    let {
        host
    } = url.parse(urlAddr);
    return removePort(host);
}

function request(req, res) {
    let refer = req.headers['referer'] || req.headers['referrer'];
    if (refer) {
        let referHost = getHostName(refer);
        let host = removePort(req.headers['host']);
        if (referHost != host) {
            sendForbidden(req, res);
        } else {
            serve(req, res);
        }
    } else {
        serve(req, res);
    }
}

function serve(req, res) {
    let {
        pathname
    } = url.parse(req.url);
    let filepath = path.join(root, pathname);
    console.log(req.url, filepath);

    fs.stat(filepath, (err, stat) => {
        if (err) {
            res.end('Not Found');
        } else {
            fs.createReadStream(filepath).pipe(res);
        }
    });
}

function sendForbidden(req, res) {
    res.end('防盗链');
}
let server = http.createServer();
server.on('request', request);
server.listen(8080);
//-H "referer: http://xxx.xxx.xxx.xxx"   http://localhost:8080/mv.jpg

4. 代理服务器 #

代理（英语：Proxy），也称网络代理，是一种特殊的网络服务，允许一个网络终端（一般为客户端）通过这个服务与另一个网络终端（一般为服务器）进行非直接的连接。一些网关、路由器等网络设备具备网络代理功能。一般认为代理服务有利于保障网络终端的隐私或安全，防止攻击。

npm install http-proxy --save

https://www.npmjs.com/package/http-proxy

let httpProxy = require('http-proxy');
let http = require('http');
let proxy = httpProxy.createProxyServer();

http.createServer(function (req, res) {
    proxy.web(req, res, {
        target: 'http://localhost:8000'
    });
    proxy.on('error', function (err) {
        console.log('出错了');
        res.end(err.toString());
    });
}).listen(8080);

5. 虚拟主机 #

通过Host实现多个网站共用一个端口,多个网站共用一个服务器

let http = require('http');
let httpProxy = require('http-proxy');
let proxy = httpProxy.createProxyServer();

let hosts = {
    'a.zfpx.cn': 'http://localhost:8000',
    'b.zfpx.cn': 'http://localhost:9000'
}
let server = http.createServer(function (req, res) {
    let host = req.headers['host'];
    host = host.split(':')[0];
    let target = hosts[host];
    proxy.web(req, res, {
        target
    });

}).listen(80);

6. User-Agent #

User Agent中文名为用户代理，简称 UA，它是一个特殊字符串头，使得服务器能够识别客户使用的操作系统及版本、CPU 类型、浏览器及版本、浏览器渲染引擎、浏览器语言、浏览器插件等。