利用 Cloudflare Workers 构建 GitHub 镜像加速站：实现快速访问并优化资源加载流程

对于国内的同学来说，如果不挂代理，访问 github 是不太稳定的，网上也有很多的 github 加速方法，如果你也想拥有一个属于自己独享的 github 加速，可以按照此教程（基于开源项目 gh-proxy）。

步骤如下

登陆你的 cloudflare 账号 ，点击左边侧栏的 Workers，然后点击创建服务

服务名称填上你的，随便起，链接上会体现的，其他的默认不动，填完点击创建服务

然后点击快速编辑

复制下面的代码粘贴，github 源码

'use strict'

/**
 * static files (404.html, sw.js, conf.js)
 */
const ASSET_URL = 'https://hunshcn.github.io/gh-proxy/'
// 前缀，如果自定义路由为 example.com/gh/*，将 PREFIX 改为 '/gh/'，注意，少一个杠都会错！const PREFIX = '/'
// git 使用 cnpmjs 镜像、分支文件使用 jsDelivr 镜像的开关，0 为关闭，默认开启
const Config = {
    jsdelivr: 1,
    cnpmjs: 1
}

/** @type {RequestInit} */
const PREFLIGHT_INIT = {
    status: 204,
    headers: new Headers({
        'access-control-allow-origin': '*',
        'access-control-allow-methods': 'GET,POST,PUT,PATCH,TRACE,DELETE,HEAD,OPTIONS',
        'access-control-max-age': '1728000',
    }),
}


const exp1 = /^(?:https?://)?github.com/.+?/.+?/(?:releases|archive)/.*$/i
const exp2 = /^(?:https?://)?github.com/.+?/.+?/(?:blob|raw)/.*$/i
const exp3 = /^(?:https?://)?github.com/.+?/.+?/(?:info|git-).*$/i
const exp4 = /^(?:https?://)?raw.(?:githubusercontent|github).com/.+?/.+?/.+?/.+$/i
const exp5 = /^(?:https?://)?gist.(?:githubusercontent|github).com/.+?/.+?/.+$/i
const exp6 = /^(?:https?://)?github.com/.+?/.+?/tags.*$/i

/**
 * @param {any} body
 * @param {number} status
 * @param {Object<string, string>} headers
 */
function makeRes(body, status = 200, headers = {}) {headers['access-control-allow-origin'] = '*'
    return new Response(body, {status, headers})
}


/**
 * @param {string} urlStr
 */
function newUrl(urlStr) {
    try {return new URL(urlStr)
    } catch (err) {return null}
}


addEventListener('fetch', e => {const ret = fetchHandler(e)
        .catch(err => makeRes('cfworker error:n' + err.stack, 502))
    e.respondWith(ret)
})


function checkUrl(u) {for (let i of [exp1, exp2, exp3, exp4, exp5, exp6]) {if (u.search(i) === 0) {return true}
    }
    return false
}

/**
 * @param {FetchEvent} e
 */
async function fetchHandler(e) {
    const req = e.request
    const urlStr = req.url
    const urlObj = new URL(urlStr)
    let path = urlObj.searchParams.get('q')
    if (path) {return Response.redirect('https://' + urlObj.host + PREFIX + path, 301)
    }
    // cfworker 会把路径中的 `//` 合并成 `/`
    path = urlObj.href.substr(urlObj.origin.length + PREFIX.length).replace(/^https?:/+/, 'https://')
    if (path.search(exp1) === 0 || path.search(exp5) === 0 || path.search(exp6) === 0 || !Config.cnpmjs && (path.search(exp3) === 0 || path.search(exp4) === 0)) {return httpHandler(req, path)
    } else if (path.search(exp2) === 0) {if (Config.jsdelivr) {const newUrl = path.replace('/blob/', '@').replace(/^(?:https?://)?github.com/, 'https://cdn.jsdelivr.net/gh')
            return Response.redirect(newUrl, 302)
        } else {path = path.replace('/blob/', '/raw/')
            return httpHandler(req, path)
        }
    } else if (path.search(exp3) === 0) {const newUrl = path.replace(/^(?:https?://)?github.com/, 'https://github.com.cnpmjs.org')
        return Response.redirect(newUrl, 302)
    } else if (path.search(exp4) === 0) {const newUrl = path.replace(/(?<=com/.+?/.+?)/(.+?/)/, '@$1').replace(/^(?:https?://)?raw.(?:githubusercontent|github).com/, 'https://cdn.jsdelivr.net/gh')
        return Response.redirect(newUrl, 302)
    } else {return fetch(ASSET_URL + path)
    }
}


/**
 * @param {Request} req
 * @param {string} pathname
 */
function httpHandler(req, pathname) {
    const reqHdrRaw = req.headers

    // preflight
    if (req.method === 'OPTIONS' &&
        reqHdrRaw.has('access-control-request-headers')
    ) {return new Response(null, PREFLIGHT_INIT)
    }

    const reqHdrNew = new Headers(reqHdrRaw)

    let urlStr = pathname
    if (urlStr.startsWith('github')) {urlStr = 'https://' + urlStr}
    const urlObj = newUrl(urlStr)

    /** @type {RequestInit} */
    const reqInit = {
        method: req.method,
        headers: reqHdrNew,
        redirect: 'manual',
        body: req.body
    }
    return proxy(urlObj, reqInit)
}


/**
 *
 * @param {URL} urlObj
 * @param {RequestInit} reqInit
 */
async function proxy(urlObj, reqInit) {const res = await fetch(urlObj.href, reqInit)
    const resHdrOld = res.headers
    const resHdrNew = new Headers(resHdrOld)

    const status = res.status

    if (resHdrNew.has('location')) {let _location = resHdrNew.get('location')
        if (checkUrl(_location))
            resHdrNew.set('location', PREFIX + _location)
        else {
            reqInit.redirect = 'follow'
            return proxy(newUrl(_location), reqInit)
        }
    }
    resHdrNew.set('access-control-expose-headers', '*')
    resHdrNew.set('access-control-allow-origin', '*')

    resHdrNew.delete('content-security-policy')
    resHdrNew.delete('content-security-policy-report-only')
    resHdrNew.delete('clear-site-data')

    return new Response(res.body, {
        status,
        headers: resHdrNew,
    })
}

把复制的代码粘贴到左边处替换所有代码，先点保存部署，然后再点到发送

如果显示 200 OK 的话就成算成功了，你可以复制你的链接分享给你的朋友或者自己做 github 加速用了

当你你也可以使用我搭建的，也可以分享给你的朋友用，免费账户每天 10 万请求，应该够个人用吧。

这是我搭建的 github 加速地址：https://github.abskoop.workers.dev/

本教程基于开源项目 gh-proxy：https://github.com/hunshcn/gh-proxy