事情大概是这样子的，很早就知道 cloudflare是个好东西，很多功能对于免费用户都是直接开放的，比如 ssl证书和cdn，以及我的技术博客用的page功能也是免费的。最近了解到 work功能可以用来做反向代理的，和我想的一样这功能肯定有人用来反代谷歌。所以也尝试了一下，没想到翻车了。记录一下配置过程吧
在开始之前首先需要准备
- cloudflare账号一个
- 域名一个
1. 创建一个 worker
// 反代目标网站.const upstream = 'www.google.com'// 反代目标网站的移动版.const upstream_mobile = 'www.google.com'// 访问区域黑名单（按需设置）.const blocked_region = ['TK']// IP地址黑名单（按需设置）.const blocked_ip_address = ['0.0.0.0', '127.0.0.1']// 路径替换.const replace_dict = {'$upstream': '$custom_domain','//archiveofourown.org': ''}addEventListener('fetch', event => {event.respondWith(fetchAndApply(event.request));})async function fetchAndApply(request) {const region = request.headers.get('cf-ipcountry').toUpperCase();const ip_address = request.headers.get('cf-connecting-ip');const user_agent = request.headers.get('user-agent');let response = null;let url = new URL(request.url);let url_host = url.host;if (url.protocol == 'http:') {url.protocol = 'https:'response = Response.redirect(url.href);return response;}if (await device_status(user_agent)) {var upstream_domain = upstream;} else {var upstream_domain = upstream_mobile;}url.host = upstream_domain;if (blocked_region.includes(region)) {response = new Response('Access denied: WorkersProxy is not available in your region yet.', {status: 403});} else if(blocked_ip_address.includes(ip_address)){response = new Response('Access denied: Your IP address is blocked by WorkersProxy.', {status: 403});} else{let method = request.method;let request_headers = request.headers;let new_request_headers = new Headers(request_headers);new_request_headers.set('Host', upstream_domain);new_request_headers.set('Referer', url.href);let original_response = await fetch(url.href, {method: method,headers: new_request_headers})let original_response_clone = original_response.clone();let original_text = null;let response_headers = original_response.headers;let new_response_headers = new Headers(response_headers);let status = original_response.status;new_response_headers.set('cache-control' ,'public, max-age=14400')new_response_headers.set('access-control-allow-origin', '*');new_response_headers.set('access-control-allow-credentials', true);new_response_headers.delete('content-security-policy');new_response_headers.delete('content-security-policy-report-only');new_response_headers.delete('clear-site-data');const content_type = new_response_headers.get('content-type');if (content_type.includes('text/html') && content_type.includes('UTF-8')) {original_text = await replace_response_text(original_response_clone, upstream_domain, url_host);} else {original_text = original_response_clone.body}response = new Response(original_text, {status,headers: new_response_headers})}return response;}async function replace_response_text(response, upstream_domain, host_name) {let text = await response.text()var i, j;for (i in replace_dict) {j = replace_dict[i]if (i == '$upstream') {i = upstream_domain} else if (i == '$custom_domain') {i = host_name}if (j == '$upstream') {j = upstream_domain} else if (j == '$custom_domain') {j = host_name}let re = new RegExp(i, 'g')text = text.replace(re, j);}return text;}async function device_status (user_agent_info) {var agents = ["Android", "iPhone", "SymbianOS", "Windows Phone", "iPad", "iPod"];var flag = true;for (var v = 0; v < agents.length; v++) {if (user_agent_info.indexOf(agents[v]) > 0) {flag = false;break;}}return flag;}4. 最后体验发现，翻车了，提示以下错误网上搜索和研究了一下，发现这个是由于谷歌的对于反向代理的一个封禁措施，和 ip有关系这个基本上说明基于 cf的反代谷歌的白嫖这条路子断了，白嫖失败。
