[短链][Worker] 利用Cloudflare及KV搭建可自定义路径的短链程序

https://wlnxing.com/archives/62.html

简介

一个部署在Cloudflare-Worker上的简单短链程序，可自定义短链的路径，上手简单，适合个人小范围使用。

GitHub地址: https://github.com/wlnxing/URL-Shorten-Worker

预览

用法

在 "长链接" 框输入要缩短的长链接, 在下面的自定义路径处填写短链接的路径 (没有填写的话会自动生成一个随机路径) , 然后点击提交即可

自定义链接的最前面不用加/

部署

登录Cloudflare

去cloudflare登录或者创建账号，并绑定好域名。

创建KV命名空间

选择你要需要使用的域名，在右侧菜单中选择workers-->kv

选择创建命名空间，输入命名空间的名称，然后点击添加

创建workers

到右侧菜单点击worker(概述),点击创建服务

随后输入worker的名称，完成后点击创建

复制项目里的`worker.js`的代码到Worker里

worker.js

const html404 = `<!DOCTYPE html>
<body>
  <h1>404 Not Found.</h1>
  <p>The url you visit is not found.</p>
</body>`

const statichtml = "https://wlnxing.github.io/URL-Shorten-Worker/index.html"


async function randomString (len) {
    len = len || 6
    let $chars = 'ABCDEFGHJKMNPQRSTWXYZabcdefhijkmnprstwxyz2345678'    /****默认去掉了容易混淆的字符oOLl,9gq,Vv,Uu,I1****/
    let maxPos = $chars.length
    let result = ''
    for (let i = 0; i < len; i++) {
        result += $chars.charAt(Math.floor(Math.random() * maxPos))
    }
    return result
}
async function checkURL (URL) {
    let str = URL
    let Expression = /http(s)?:\/\/([\w-]+\.)+[\w-]+(\/[\w- .\/?%&=]*)?/
    let objExp = new RegExp(Expression)
    return objExp.test(str) && str[0] === 'h'
}
async function save_url (URL, shortStr) {
    console.log("shortStr:", shortStr)
    let random_key
    if (!shortStr) {
        random_key = await randomString()
    } else {
        random_key = shortStr
    }
    let is_exist = await LINKS.get(random_key)
    console.log(is_exist)
    if (is_exist == null) {
        // 正常，直接放入
        let stat = await LINKS.put(random_key, URL)
        if (typeof (stat) === "undefined") return random_key
        else return stat
    } else if (!shortStr) {
        // 生成的random_key重复了，递归调用
        return save_url(URL, null)
    } else
        // 自定义的路径已经存在了
        return -1

}
async function handleRequest (request) {
    console.log(request)
    if (request.method === "POST") {
        let req = await request.json()
        console.log(req["url"])
        if (!await checkURL(req["url"]))
            return new Response(`{"msg":"URL错误"}`, { status: 400, headers: { "Content-Type": "application/json" } })
        let random_key = await save_url(req["url"], req["shortStr"])
        console.log(random_key)
        // 放成功了
        if (Object.prototype.toString.call(random_key) === "[object String]")
            return new Response(`{"data":{"shortUrl":"${random_key}"}}`, { status: 200, headers: { "Content-Type": "application/json" } })
        // 自定义的路径重复了
        else if (random_key === -1)
            return new Response(`{"msg":"自定义路径已重复"}`, { status: 400, headers: { "Content-Type": "application/json" } })
        // 没测试k-v满了之后会怎么样，如果有错的话put时应该会有返回（猜测（懒
        else return new Response(`{"msg":"k-v限额已满，求放过别刷啦"}`, { status: 500, headers: { "Content-Type": "application/json" } })
    }
    const requestURL = new URL(request.url)
    // todo 规范路径的'/'
    const path = requestURL.pathname.toString().substring(1);
    console.log(path)
    if (!path) {

        const html = await fetch(statichtml)

        return new Response(await html.text(), {
            headers: {
                "content-type": "text/html;charset=UTF-8",
            },
        })
    }
    const value = await LINKS.get(path)
    console.log(value)


    const location = value
    if (location) {
        return Response.redirect(location, 302)

    }
    // If request not in kv, return 404
    return new Response(html404, {
        headers: {
            "content-type": "text/html;charset=UTF-8",
        },
        status: 404
    })
}



addEventListener("fetch", async event => {
    event.respondWith(handleRequest(event.request))
})