perf(electron): bound lightweight readiness polling

Author: backryun

electron/lib/serverReadiness.js

@@ -0,0 +1,61 @@
+/**
+ * Pure helpers for polling the embedded or remote OmniRoute server without
+ * importing the Electron main process.
+ */
+
+const DEFAULT_TIMEOUT_MS = 180000;
+const DEFAULT_REQUEST_TIMEOUT_MS = 2000;
+const DEFAULT_POLL_INTERVAL_MS = 500;
+
+function buildReadinessUrl(baseUrl) {
+  return `${baseUrl.replace(/\/+$/, "")}/api/health/ping`;
+}
+
+async function waitForServer(url, timeoutMs = DEFAULT_TIMEOUT_MS, options = {}) {
+  const {
+    fetchFn = globalThis.fetch,
+    requestTimeoutMs = DEFAULT_REQUEST_TIMEOUT_MS,
+    pollIntervalMs = DEFAULT_POLL_INTERVAL_MS,
+    nowFn = Date.now,
+    sleepFn = (delayMs) => new Promise((resolve) => setTimeout(resolve, delayMs)),
+    warnFn = console.warn,
+  } = options;
+
+  const startedAt = nowFn();
+  while (nowFn() - startedAt < timeoutMs) {
+    const remainingMs = timeoutMs - (nowFn() - startedAt);
+    const attemptTimeoutMs = Math.max(1, Math.min(requestTimeoutMs, remainingMs));
+    const controller = new AbortController();
+    let timeoutId;
+
+    try {
+      const response = await Promise.race([
+        fetchFn(url, { signal: controller.signal }),
+        new Promise((resolve) => {
+          timeoutId = setTimeout(() => {
+            controller.abort();
+            resolve(null);
+          }, attemptTimeoutMs);
+        }),
+      ]);
+
+      if (response?.ok) return true;
+    } catch {
+      /* server not ready yet */
+    } finally {
+      if (timeoutId !== undefined) clearTimeout(timeoutId);
+    }
+
+    const pollRemainingMs = timeoutMs - (nowFn() - startedAt);
+    if (pollRemainingMs <= 0) break;
+    await sleepFn(Math.min(pollIntervalMs, pollRemainingMs));
+  }
+
+  warnFn("[Electron] Server readiness timeout — showing window anyway");
+  return false;
+}
+
+module.exports = {
+  buildReadinessUrl,
+  waitForServer,
+};

electron/main.js

@@ -39,6 +39,7 @@ const { resolveServerEntry } = require("./lib/resolveServerEntry");
 const { resolveDarwinHelperExecutable } = require("./lib/resolveNodeHelper");
 const { resolveRemoteServerUrl, isValidHttpUrl } = require("./lib/resolveRemoteServerUrl");
 const { writeRemoteServerUrl } = require("./lib/remoteServerPreferences");
+const { buildReadinessUrl, waitForServer } = require("./lib/serverReadiness");
 
 // ── Single Instance Lock ───────────────────────────────────
 const gotTheLock = app.requestSingleInstanceLock();
@@ -86,6 +87,7 @@ let remoteServerUrl = resolveRemoteServerUrl({
 });
 
 const getServerUrl = () => remoteServerUrl || `http://localhost:${serverPort}`;
+const getServerReadinessUrl = () => buildReadinessUrl(getServerUrl());
 
 function resolveNodeExecutable(env = process.env) {
   // #1081: Ensure Next.js standalone runs using Electron's Node runtime
@@ -185,26 +187,6 @@ function sendToRenderer(channel, data) {
   }
 }
 
-// ── Helper: Wait for server readiness (#1, #10) ────────────
-// Default raised to 180s: the first launch after an upgrade can run long DB
-// migrations, during which the server accepts the TCP connection but holds the
-// HTTP response until handlers initialize. The previous 30s cap timed out and
-// left the window stuck on a hanging connection (#2460).
-async function waitForServer(url, timeoutMs = 180000) {
-  const start = Date.now();
-  while (Date.now() - start < timeoutMs) {
-    try {
-      const res = await fetch(url);
-      if (res.ok || res.status < 500) return true;
-    } catch {
-      /* server not ready yet */
-    }
-    await new Promise((r) => setTimeout(r, 500));
-  }
-  console.warn("[Electron] Server readiness timeout — showing window anyway");
-  return false;
-}
-
 // ── Helper: Wait for server process exit with timeout (#2) ─
 async function waitForServerExit(proc, timeoutMs = 5000) {
   if (!proc) return;
@@ -533,7 +515,7 @@ async function changePort(newPort) {
 
   // Start server on new port
   startNextServer();
-  await waitForServer(getServerUrl());
+  await waitForServer(getServerReadinessUrl());
 
   // Reload window and update tray
   if (mainWindow && !mainWindow.isDestroyed()) {
@@ -603,7 +585,7 @@ async function setRemoteServerUrl(nextUrl) {
 
   startNextServer();
   try {
-    await waitForServer(`${getServerUrl()}/api/monitoring/health`);
+    await waitForServer(getServerReadinessUrl());
   } catch (err) {
     console.warn("[Electron] Server did not become ready after remote-server change:", err.message);
   }
@@ -935,7 +917,7 @@ function setupIpcHandlers() {
     stopNextServer();
     await waitForServerExit(serverToStop);
     startNextServer();
-    await waitForServer(getServerUrl());
+    await waitForServer(getServerReadinessUrl());
     return { success: true };
   });
 
@@ -1078,8 +1060,8 @@ app.whenReady().then(async () => {
   startNextServer();
   let serverReady = true;
   if (!isDev) {
-    // Probe the auth-exempt health endpoint (not the root URL, which may redirect).
-    serverReady = await waitForServer(`${getServerUrl()}/api/monitoring/health`);
+    // Probe the lightweight auth-exempt endpoint instead of aggregating full monitoring state.
+    serverReady = await waitForServer(getServerReadinessUrl());
   }
 
   if (isHeadless) {
@@ -1095,7 +1077,7 @@ app.whenReady().then(async () => {
   // If readiness timed out (e.g. very long first-launch migrations), don't leave the
   // window stuck on a hanging connection — keep polling and reload once it responds (#2460).
   if (!isDev && !serverReady && !isHeadless) {
-    void waitForServer(`${getServerUrl()}/api/monitoring/health`, 300000).then((ready) => {
+    void waitForServer(getServerReadinessUrl(), 300000).then((ready) => {
       if (ready && mainWindow && !mainWindow.isDestroyed()) {
         mainWindow.loadURL(getServerUrl());
       }

electron/package.json

@@ -66,6 +66,7 @@
       "lib/resolveNodeHelper.js",
       "lib/resolveRemoteServerUrl.js",
       "lib/remoteServerPreferences.js",
+      "lib/serverReadiness.js",
       "assets/remoteServerPrompt.html",
       "package.json",
       "node_modules/**/*"

tests/unit/electron-main.test.ts

@@ -19,6 +19,7 @@ import { join } from "node:path";
 import { createRequire } from "node:module";
 
 const require = createRequire(import.meta.url);
+const { waitForServer } = require("../../electron/lib/serverReadiness");
 
 function raceDelays(firstMs, secondMs) {
   return new Promise((resolve) => {
@@ -272,23 +273,12 @@ describe("Server Port Management", () => {
 
 describe("Server Readiness Logic", () => {
   it("waitForServer should timeout and return false", async () => {
-    // Simulate the polling logic with an always-failing fetch
-    async function waitForServer(url, timeoutMs = 100) {
-      const start = Date.now();
-      while (Date.now() - start < timeoutMs) {
-        try {
-          const res = await fetch(url);
-          if (res.ok || res.status < 500) return true;
-        } catch {
-          /* not ready */
-        }
-        await new Promise((r) => setTimeout(r, 30));
-      }
-      return false;
-    }
-
-    // Should timeout immediately since nothing is running on that port
-    const result = await waitForServer("http://localhost:59999", 100);
+    const result = await waitForServer("http://localhost:59999/api/health/ping", 20, {
+      fetchFn: async () => ({ ok: false }),
+      pollIntervalMs: 1,
+      requestTimeoutMs: 5,
+      warnFn: () => {},
+    });
     assert.equal(result, false);
   });
 
@@ -302,18 +292,20 @@ describe("Server Readiness Logic", () => {
       serverUp = true;
     }, 60);
 
-    async function waitForServer(_url, timeoutMs) {
-      const start = Date.now();
-      while (Date.now() - start < timeoutMs) {
-        if (serverUp) return true;
-        await new Promise((r) => setTimeout(r, 15));
-      }
-      return false;
-    }
+    const readinessOptions = {
+      fetchFn: async () => ({ ok: serverUp }),
+      pollIntervalMs: 5,
+      requestTimeoutMs: 5,
+      warnFn: () => {},
+    };
 
     try {
       // Initial probe with a short budget times out (server not up yet).
-      const initialReady = await waitForServer("http://localhost/api/monitoring/health", 20);
+      const initialReady = await waitForServer(
+        "http://localhost/api/health/ping",
+        20,
+        readinessOptions
+      );
       assert.equal(initialReady, false);
 
       let reloaded = false;
@@ -325,7 +317,11 @@ describe("Server Readiness Logic", () => {
       };
 
       // Background retry with a generous budget should succeed and reload the window.
-      const retryReady = await waitForServer("http://localhost/api/monitoring/health", 5000);
+      const retryReady = await waitForServer(
+        "http://localhost/api/health/ping",
+        5000,
+        readinessOptions
+      );
       if (retryReady && mainWindow && !mainWindow.isDestroyed()) {
         mainWindow.loadURL("http://localhost");
       }

tests/unit/electron-server-readiness.test.ts

@@ -0,0 +1,57 @@
+import assert from "node:assert/strict";
+import { createRequire } from "node:module";
+import { describe, it } from "node:test";
+
+const require = createRequire(import.meta.url);
+const { buildReadinessUrl, waitForServer } = require("../../electron/lib/serverReadiness");
+
+describe("Electron server readiness", () => {
+  it("builds the lightweight readiness URL from local and remote base URLs", () => {
+    assert.equal(
+      buildReadinessUrl("http://localhost:20128"),
+      "http://localhost:20128/api/health/ping"
+    );
+    assert.equal(
+      buildReadinessUrl("https://omniroute.example.com/"),
+      "https://omniroute.example.com/api/health/ping"
+    );
+  });
+
+  it("accepts only a successful HTTP response", async () => {
+    let attempts = 0;
+    const ready = await waitForServer("http://localhost/api/health/ping", 100, {
+      fetchFn: async () => ({ ok: ++attempts === 2 }),
+      pollIntervalMs: 1,
+      requestTimeoutMs: 20,
+      warnFn: () => {},
+    });
+
+    assert.equal(ready, true);
+    assert.equal(attempts, 2);
+  });
+
+  it("returns false after repeated unsuccessful responses", async () => {
+    const ready = await waitForServer("http://localhost/api/health/ping", 20, {
+      fetchFn: async () => ({ ok: false }),
+      pollIntervalMs: 1,
+      requestTimeoutMs: 5,
+      warnFn: () => {},
+    });
+
+    assert.equal(ready, false);
+  });
+
+  it("bounds a stalled request by both the attempt and overall deadlines", async () => {
+    const startedAt = Date.now();
+    const ready = await waitForServer("http://localhost/api/health/ping", 35, {
+      fetchFn: () => new Promise(() => {}),
+      pollIntervalMs: 1,
+      requestTimeoutMs: 10,
+      warnFn: () => {},
+    });
+    const elapsedMs = Date.now() - startedAt;
+
+    assert.equal(ready, false);
+    assert.ok(elapsedMs < 150, `stalled readiness probe took ${elapsedMs}ms`);
+  });
+});