fix(website): cache GitHub stars on server for 3 hours (#730)

Move star count fetching from universal +layout.ts to server-only code
so the GitHub API is not called on every page load or client navigation.

Add an in-memory cache with a 3-hour TTL and in-flight request
deduplication. On API errors (including rate limits), return the last
successful value when available.

Co-authored-by: Cursor Agent <[email protected]>
Co-authored-by: Rotimi Best <[email protected]>

apps/website/src/lib/server/github-stars.ts

@@ -0,0 +1,68 @@
+const GITHUB_REPO_URL = 'https://api.github.com/repos/classroomio/classroomio';
+const CACHE_TTL_MS = 1000 * 60 * 60 * 3;
+
+const starsCache = {
+  stars: 0,
+  lastUpdated: 0
+};
+
+let inFlightFetch: Promise<number> | null = null;
+
+function isCacheFresh(now: number) {
+  return starsCache.lastUpdated > 0 && now - starsCache.lastUpdated < CACHE_TTL_MS;
+}
+
+export async function getGithubStars(): Promise<number> {
+  const now = Date.now();
+
+  if (isCacheFresh(now)) {
+    return starsCache.stars;
+  }
+
+  if (inFlightFetch) {
+    return inFlightFetch;
+  }
+
+  inFlightFetch = fetchGithubStars(now).finally(() => {
+    inFlightFetch = null;
+  });
+
+  return inFlightFetch;
+}
+
+async function fetchGithubStars(now: number): Promise<number> {
+  try {
+    const response = await fetch(GITHUB_REPO_URL, {
+      headers: {
+        Accept: 'application/vnd.github+json',
+        'User-Agent': 'classroomio-website'
+      }
+    });
+
+    if (!response.ok) {
+      console.error('getGithubStars error: GitHub API returned', response.status);
+
+      if (starsCache.lastUpdated > 0) {
+        return starsCache.stars;
+      }
+
+      return 0;
+    }
+
+    const data = await response.json();
+    const stars = typeof data?.stargazers_count === 'number' ? data.stargazers_count : 0;
+
+    starsCache.stars = stars;
+    starsCache.lastUpdated = now;
+
+    return stars;
+  } catch (error) {
+    console.error('getGithubStars error:', error);
+
+    if (starsCache.lastUpdated > 0) {
+      return starsCache.stars;
+    }
+
+    return 0;
+  }
+}

apps/website/src/routes/+layout.server.ts

@@ -0,0 +1,7 @@
+import { getGithubStars } from '$lib/server/github-stars';
+
+export async function load() {
+  const stars = await getGithubStars();
+
+  return { stars };
+}

apps/website/src/routes/+layout.ts

@@ -3,50 +3,18 @@ import type { MetaTagsProps } from 'svelte-meta-tags';
 export const prerender = true;
 
 export async function load({ url }) {
-  const stars = await getStars();
-
   return {
     baseMetaTags: getBaseMetaTags(url),
-    url: url.pathname,
-    stars
+    url: url.pathname
   };
 }
 
-const starsCache = new Map<string, { stars: number; lastUpdated: number }>();
-const CACHE_TIME = 1000 * 60 * 60 * 48; // 48 hours
-const CACHE_KEY = 'github-stars';
 const DEFAULT_META_TITLE = 'ClassroomIO | One Platform for Customer, Partner, and Employee Training';
 const DEFAULT_META_DESCRIPTION =
   'One platform for customer academies, partner certification, and employee training. Build courses with AI, publish under your domain, and track completions.';
 const DEFAULT_OG_IMAGE_URL = 'https://brand.cdn.clsrio.com/og/classroomio-opengraph.jpg';
 const DEFAULT_OG_IMAGE_ALT = 'ClassroomIO platform for customer, partner, and employee education';
 
-async function getStars() {
-  const now = Date.now();
-
-  const cacheData = starsCache.get(CACHE_KEY);
-  if (cacheData && now - cacheData.lastUpdated < CACHE_TIME) {
-    console.log('Returning cached stars');
-    return cacheData.stars;
-  }
-
-  console.log('Fetching stars from GitHub');
-
-  let stars = 0;
-
-  try {
-    const response = await fetch('https://api.github.com/repos/classroomio/classroomio');
-    const data = await response.json();
-    stars = data?.stargazers_count || 0;
-  } catch (error) {
-    console.log('error fetching stars', error);
-  }
-
-  starsCache.set(CACHE_KEY, { stars, lastUpdated: now });
-
-  return stars;
-}
-
 function getBaseMetaTags(url: URL) {
   const canonicalUrl = new URL(url.pathname, url.origin).href;