feat: add CORS proxy for subscription fetch

public/index.html

@@ -431,15 +431,17 @@
       if (!url) return toast('请输入订阅链接', 'error');
 
       try {
-        toast('正在从浏览器获取订阅...', 'info');
+        toast('正在获取订阅...', 'info');
 
-        // Fetch subscription from browser side (avoids server network issues)
-        const resp = await fetch(url, {
-          headers: { 'User-Agent': 'ClashForAndroid/2.5.12' },
-          mode: 'cors',
-        });
-        if (!resp.ok) throw new Error('HTTP ' + resp.status);
-        let content = await resp.text();
+        // Use server-side proxy to fetch (bypasses CORS)
+        const fetchRes = await api('POST', '/api/proxy-fetch', { url });
+        if (fetchRes.error) throw new Error(fetchRes.error);
+        let content = fetchRes.content;
+
+        // Check if we got HTML instead of YAML
+        if (content.trim().startsWith('<!DOCTYPE') || content.trim().startsWith('<html')) {
+          throw new Error('订阅地址返回了网页而非配置，请检查链接是否正确');
+        }
 
         // Try base64 decode
         try {
@@ -447,13 +449,13 @@
           if (decoded.includes('://') || decoded.includes('proxies')) content = decoded;
         } catch {}
 
-        if (!content.includes('proxies') && !content.includes('port:')) {
-          throw new Error('无效的订阅内容');
+        if (!content.includes('proxies') && !content.includes('port:') && !content.includes('mixed-port:')) {
+          throw new Error('无效的订阅内容，请检查链接');
         }
 
         toast('订阅获取成功，正在推送到 mihomo...', 'info');
 
-        // Send content to mihomo via our server API
+        // Push content to mihomo
         const applyRes = await api('POST', '/api/subscription/push', { content, url });
         if (applyRes.error) throw new Error(applyRes.error);
 
@@ -463,23 +465,7 @@
         loadSubscriptions();
         loadDashboard();
       } catch(e) {
-        // CORS blocked - fallback to server-side fetch
-        if (e.message.includes('Failed to fetch') || e.message.includes('NetworkError')) {
-          toast('浏览器无法直接获取（CORS），改用服务器获取...', 'info');
-          try {
-            const res = await api('POST', '/api/subscription/import', { url });
-            if (res.error) throw new Error(res.error);
-            const applyRes = await api('POST', '/api/subscription/apply', { url });
-            if (applyRes.error) throw new Error(applyRes.error);
-            toast('🎉 订阅导入成功！', 'success');
-            document.getElementById('sub-url').value = '';
-            loadSubscriptions();
-          } catch(e2) {
-            toast('导入失败: ' + e2.message, 'error');
-          }
-        } else {
-          toast('导入失败: ' + e.message, 'error');
-        }
+        toast('导入失败: ' + e.message, 'error');
       }
     }
 

server.js

@@ -355,6 +355,21 @@ async function handleApi(req, res, apiPath) {
     }
   }
 
+  // POST /api/proxy-fetch - CORS proxy: fetch URL on behalf of browser
+  if (apiPath === '/api/proxy-fetch' && method === 'POST') {
+    const body = JSON.parse(await readBody(req));
+    const { url } = body;
+    if (!url) return sendError(res, 'Missing url', 400);
+
+    try {
+      const result = await fetchUrl(url, { headers: { 'User-Agent': 'ClashForAndroid/2.5.12' } });
+      const content = result.body.toString('utf-8');
+      return sendJson(res, { ok: true, content, status: result.status });
+    } catch (e) {
+      return sendError(res, 'Fetch failed: ' + e.message);
+    }
+  }
+
   // POST /api/subscription/push - Push subscription content directly to mihomo
   if (apiPath === '/api/subscription/push' && method === 'POST') {
     const body = JSON.parse(await readBody(req));