Refine VPN client instructions and subscription refresh flow

src/server/index.js

@@ -11,14 +11,17 @@ import {
   removeSingboxConfig,
   writeSingboxConfig,
 } from './singbox.js';
-import { fetchSubscription, fetchSubscriptionInfo } from './subscription.js';
+import { fetchSubscription, selectRefreshedServer } from './subscription.js';
 
 const MAX_BODY_BYTES = 1_000_000;
+const SUBSCRIPTION_REFRESH_INTERVAL_MS = 15 * 60 * 1000;
 
 fs.mkdirSync(settings.dataDir, { recursive: true });
 
 let singboxProcess = null;
 let singboxStartedAt = null;
+let subscriptionRefreshPromise = null;
+let subscriptionRefreshTimer = null;
 
 function readJson(filePath, fallback) {
   try {
@@ -195,6 +198,69 @@ async function applySelectedServer(selectedTag) {
   });
 }
 
+function refreshSavedSubscription() {
+  if (subscriptionRefreshPromise) return subscriptionRefreshPromise;
+
+  subscriptionRefreshPromise = (async () => {
+    const initialState = readJson(settings.statePath, {});
+    if (!initialState.subscriptionUrl) {
+      const error = new Error('Подписка не настроена');
+      error.statusCode = 400;
+      throw error;
+    }
+
+    const subscriptionUrl = initialState.subscriptionUrl;
+    const parsed = await fetchSubscription(subscriptionUrl);
+    const currentState = readJson(settings.statePath, {});
+    if (currentState.subscriptionUrl !== subscriptionUrl) {
+      throw new Error('Подписка была изменена во время обновления');
+    }
+
+    const selectedTag = selectRefreshedServer(currentState.selectedTag, parsed.servers);
+    const previousCache = readJson(settings.subscriptionCachePath, null);
+    const previousConfig = fs.existsSync(settings.configPath)
+      ? fs.readFileSync(settings.configPath, 'utf8')
+      : null;
+    writeJson(settings.subscriptionCachePath, { url: subscriptionUrl, ...parsed });
+
+    try {
+      if (singboxProcess && selectedTag) await applySelectedServer(selectedTag);
+      else if (selectedTag) {
+        writeSingboxConfig(buildGatewayConfig(parsed.config, selectedTag));
+      } else {
+        removeSingboxConfig();
+      }
+    } catch (error) {
+      if (previousCache) writeJson(settings.subscriptionCachePath, previousCache);
+      else fs.rmSync(settings.subscriptionCachePath, { force: true });
+      if (previousConfig === null) removeSingboxConfig();
+      else fs.writeFileSync(settings.configPath, previousConfig, 'utf8');
+      throw error;
+    }
+
+    writeJson(settings.statePath, {
+      ...readJson(settings.statePath, {}),
+      subscriptionUrl,
+      servers: parsed.servers,
+      userInfo: parsed.userInfo,
+      fetchedAt: parsed.fetchedAt,
+      selectedTag,
+    });
+
+    return {
+      success: true,
+      servers: parsed.servers,
+      userInfo: parsed.userInfo,
+      fetchedAt: parsed.fetchedAt,
+      selectedTag,
+    };
+  })().finally(() => {
+    subscriptionRefreshPromise = null;
+  });
+
+  return subscriptionRefreshPromise;
+}
+
 async function handleApi(req, res) {
   if (req.method === 'GET' && req.url === '/api/state') {
     return sendJson(res, 200, publicState());
@@ -236,16 +302,8 @@ async function handleApi(req, res) {
     return sendJson(res, 200, { success: true, ...parsed });
   }
 
-  if (req.method === 'POST' && req.url === '/api/subscription/refresh-info') {
-    const state = readJson(settings.statePath, {});
-    if (!state.subscriptionUrl) {
-      return sendJson(res, 400, { success: false, error: 'Подписка не настроена' });
-    }
-    const info = await fetchSubscriptionInfo(state.subscriptionUrl);
-    writeJson(settings.statePath, { ...state, ...info });
-    const cached = readJson(settings.subscriptionCachePath, null);
-    if (cached) writeJson(settings.subscriptionCachePath, { ...cached, ...info });
-    return sendJson(res, 200, { success: true, ...info });
+  if (req.method === 'POST' && req.url === '/api/subscription/refresh') {
+    return sendJson(res, 200, await refreshSavedSubscription());
   }
 
   if (req.method === 'DELETE' && req.url === '/api/subscription') {
@@ -319,6 +377,7 @@ const server = http.createServer(async (req, res) => {
 });
 
 async function shutdown() {
+  clearInterval(subscriptionRefreshTimer);
   await stopSingbox();
   process.exit(0);
 }
@@ -336,3 +395,10 @@ await startSingbox().catch((error) => console.warn(`[control] sing-box не за
 server.listen(settings.port, '0.0.0.0', () => {
   console.log(`[control] ${settings.appMode} UI слушает :${settings.port}`);
 });
+
+subscriptionRefreshTimer = setInterval(() => {
+  if (!readJson(settings.statePath, {}).subscriptionUrl) return;
+  refreshSavedSubscription()
+    .catch((error) => console.warn(`[control] подписка не обновлена: ${error.message}`));
+}, SUBSCRIPTION_REFRESH_INTERVAL_MS);
+subscriptionRefreshTimer.unref();

src/server/subscription.js

@@ -160,13 +160,13 @@ async function requestSubscription(url) {
   return response;
 }
 
-export async function fetchSubscriptionInfo(url) {
-  const response = await requestSubscription(url);
-  await response.body?.cancel();
-  return {
-    userInfo: parseUserInfo(response.headers.get('subscription-userinfo')),
-    fetchedAt: new Date().toISOString(),
-  };
+export function selectRefreshedServer(currentTag, servers) {
+  const selectedTag = String(currentTag || '').trim();
+  if (!selectedTag) return '';
+
+  return servers.find((server) => String(server.tag || '').trim() === selectedTag)?.tag
+    || servers[0]?.tag
+    || '';
 }
 
 export async function fetchSubscription(url) {