用 cloudflare worker 搭建一个 Docker 镜像

感谢，另外 github 加速： https://cdn.jsdelivr.net/gh/hunshcn/gh-proxy@master/index.js

Good idea

感谢，用了下发现不能拉取 dockerhub 官方镜像（如 node 、mariadb ），正常输入
```
docker pull 域名/node
```
实际上应该为
```
docker pull 域名/library/node
```
这样有些不太方便

加上判断是否官方镜像，修改调试了些时间，成功可用
```
'use strict'

const hub_host = 'registry-1.docker.io'
const auth_url = 'https://auth.docker.io'
const workers_url = 'https://dh.jeblove.com'
/**
* static files (404.html, sw.js, conf.js)
*/

/** @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',
}),
}

/**
* @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)
})


/**
* @param {FetchEvent} e
*/
async function fetchHandler(e) {
const getReqHeader = (key) => e.request.headers.get(key);

let url = new URL(e.request.url);

// 修改 pre head get 请求
// 是否含有 %2F ，用于判断是否具有用户名与仓库名之间的连接符
// 同时检查 %3A 的存在
if (!/%2F/.test(url.search) && /%3A/.test(url.toString())) {
let modifiedUrl = url.toString().replace(/%3A(?=.*?&)/, '%3Alibrary%2F');
url = new URL(modifiedUrl);
console.log(`handle_url: ${url}`)
}

if (url.pathname === '/token') {
let token_parameter = {
headers: {
'Host': 'auth.docker.io',
'User-Agent': getReqHeader("User-Agent"),
'Accept': getReqHeader("Accept"),
'Accept-Language': getReqHeader("Accept-Language"),
'Accept-Encoding': getReqHeader("Accept-Encoding"),
'Connection': 'keep-alive',
'Cache-Control': 'max-age=0'
}
};
let token_url = auth_url + url.pathname + url.search
return fetch(new Request(token_url, e.request), token_parameter)
}

// 修改 head 请求
if (/^\/v2\/[^/]+\/[^/]+\/[^/]+$/.test(url.pathname) && !/^\/v2\/library/.test(url.pathname)) {
url.pathname = url.pathname.replace(/\/v2\//, '/v2/library/');
console.log(`modified_url: ${url.pathname}`)
}

url.hostname = hub_host;

let parameter = {
headers: {
'Host': hub_host,
'User-Agent': getReqHeader("User-Agent"),
'Accept': getReqHeader("Accept"),
'Accept-Language': getReqHeader("Accept-Language"),
'Accept-Encoding': getReqHeader("Accept-Encoding"),
'Connection': 'keep-alive',
'Cache-Control': 'max-age=0'
},
cacheTtl: 3600
};

if (e.request.headers.has("Authorization")) {
parameter.headers.Authorization = getReqHeader("Authorization");
}

let original_response = await fetch(new Request(url, e.request), parameter)
let original_response_clone = original_response.clone();
let original_text = original_response_clone.body;
let response_headers = original_response.headers;
let new_response_headers = new Headers(response_headers);
let status = original_response.status;

if (new_response_headers.get("Www-Authenticate")) {
let auth = new_response_headers.get("Www-Authenticate");
let re = new RegExp(auth_url, 'g');
new_response_headers.set("Www-Authenticate", response_headers.get("Www-Authenticate").replace(re, workers_url));
}

if (new_response_headers.get("Location")) {
return httpHandler(e.request, new_response_headers.get("Location"))
}

let response = new Response(original_text, {
status,
headers: new_response_headers
})
return response;

}


/**
* @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)
}

let rawLen = ''

const reqHdrNew = new Headers(reqHdrRaw)

const refer = reqHdrNew.get('referer')

let urlStr = pathname

const urlObj = newUrl(urlStr)

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


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

// verify
if (rawLen) {
const newLen = resHdrOld.get('content-length') || ''
const badLen = (rawLen !== newLen)

if (badLen) {
return makeRes(res.body, 400, {
'--error': `bad len: ${newLen}, except: ${rawLen}`,
'access-control-expose-headers': '--error',
})
}
}
const status = res.status
resHdrNew.set('access-control-expose-headers', '*')
resHdrNew.set('access-control-allow-origin', '*')
resHdrNew.set('Cache-Control', 'max-age=1500')

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
})
}
```
改动处：

- 57 行，添加修改 head 前的 get 请求
- 72 行，添加修改 head 请求

另外好像版本问题有额外的报错，改动有

- 12 行
- 150 行


👇
```
# docker pull xxx.com/node
Using default tag: latest
latest: Pulling from node
c6cf28de8a06: Downloading [> ] 506.8kB/49.58MB
891494355808: Downloading [========> ] 4.184MB/24.05MB
```

@jeblove 感谢～

@jeblove 使用这个拉镜像，个别层速度非常慢，是 cf 的关系吗？

@lazyyz 应该是的，毕竟得靠 cf 服务器中转流量

三楼牛逼，

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

const routes = {
"docker.域名": "https://registry-1.docker.io",
"quay.域名": "https://quay.io",
"gcr.域名": "https://gcr.io",
"k8s-gcr.域名": "https://k8s.gcr.io",
"k8s.域名": "https://registry.k8s.io",
"ghcr.域名": "https://ghcr.io",
"cloudsmith.域名": "https://docker.cloudsmith.io",
};

function routeByHosts(host) {
if (host in routes) {
return routes[host];
}
if (MODE == "debug") {
return TARGET_UPSTREAM;
}
return "";
}

async function handleRequest(request) {
let url = new URL(request.url);
const upstream = routeByHosts(url.hostname);
if (upstream === "") {
return new Response(
JSON.stringify({
routes: routes,
}),
{
status: 404,
}
);
}
if (upstream === "https://registry-1.docker.io") {
// Modify URL if necessary based on search parameters and encoded characters
if (!/%2F/.test(url.search) && /%3A/.test(url.toString())) {
let modifiedUrl = url.toString().replace(/%3A(?=.*?&)/, '%3Alibrary%2F');
url = new URL(modifiedUrl);
}

// Append 'library' to the pathname if necessary
const libraryPathPattern = /^\/v2\/[^/]+\/[^/]+\/[^/]+$/;
const libraryPrefixPattern = /^\/v2\/library/;
if (libraryPathPattern.test(url.pathname) && !libraryPrefixPattern.test(url.pathname)) {
url.pathname = url.pathname.replace(/\/v2\//, '/v2/library/');
}
}
// check if need to authenticate
if (url.pathname == "/v2/") {
const newUrl = new URL(upstream + "/v2/");
const resp = await fetch(newUrl.toString(), {
method: "GET",
redirect: "follow",
});
if (resp.status === 200) {
} else if (resp.status === 401) {
const headers = new Headers();
if (MODE == "debug") {
headers.set(
"Www-Authenticate",
`Bearer realm="${LOCAL_ADDRESS}/v2/auth",service="cloudflare-docker-proxy"`
);
} else {
headers.set(
"Www-Authenticate",
`Bearer realm="https://${url.hostname}/v2/auth",service="cloudflare-docker-proxy"`
);
}
return new Response(JSON.stringify({ message: "UNAUTHORIZED" }), {
status: 401,
headers: headers,
});
} else {
return resp;
}
}
// get token
if (url.pathname == "/v2/auth") {
const newUrl = new URL(upstream + "/v2/");
const resp = await fetch(newUrl.toString(), {
method: "GET",
redirect: "follow",
});
if (resp.status !== 401) {
return resp;
}
const authenticateStr = resp.headers.get("WWW-Authenticate");
if (authenticateStr === null) {
return resp;
}
const wwwAuthenticate = parseAuthenticate(authenticateStr);
return await fetchToken(wwwAuthenticate, url.searchParams);
}
// foward requests
const newUrl = new URL(upstream + url.pathname);
const newReq = new Request(newUrl, {
method: request.method,
headers: request.headers,
redirect: "follow",
});
return await fetch(newReq);
}

function parseAuthenticate(authenticateStr) {
// sample: Bearer realm="https://auth.ipv6.docker.com/token",service="registry.docker.io"
// match strings after =" and before "
const re = /(?<=\=")(?:\\.|[^"\\])*(?=")/g;
const matches = authenticateStr.match(re);
if (matches === null || matches.length < 2) {
throw new Error(`invalid Www-Authenticate Header: ${authenticateStr}`);
}
return {
realm: matches[0],
service: matches[1],
};
}

async function fetchToken(wwwAuthenticate, searchParams) {
const url = new URL(wwwAuthenticate.realm);
if (wwwAuthenticate.service.length) {
url.searchParams.set("service", wwwAuthenticate.service);
}
if (searchParams.get("scope")) {
url.searchParams.set("scope", searchParams.get("scope"));
}
return await fetch(url, { method: "GET", headers: {} });
}