Turn off prerendering for posts

package.json

@@ -5,7 +5,7 @@
 	"type": "module",
 	"scripts": {
 		"dev": "vite dev",
-		"build": "vite build",
+		"build": "ORIGIN=${ORIGIN:-https://www.maier.tech} vite build",
 		"start": "node build/index.js",
 		"preview": "vite preview",
 		"prepare": "svelte-kit sync || echo ''",

src/lib/server/resolvers/resolvePost.ts

@@ -10,6 +10,48 @@ import type {
 import { getAuthor, getLastCommit, getOgImageUrl, getTag } from '@maiertech/sveltekit-helpers';
 import type { RequestEvent } from '@sveltejs/kit';
 
+// Semaphore to limit concurrent API calls during prerendering
+class Semaphore {
+	private permits: number;
+	private queue: Array<() => void> = [];
+
+	constructor(permits: number) {
+		this.permits = permits;
+	}
+
+	async acquire(): Promise<void> {
+		if (this.permits > 0) {
+			this.permits--;
+			return Promise.resolve();
+		}
+		return new Promise((resolve) => {
+			this.queue.push(resolve);
+		});
+	}
+
+	release(): void {
+		const resolve = this.queue.shift();
+		if (resolve) {
+			resolve();
+		} else {
+			this.permits++;
+		}
+	}
+
+	async execute<T>(fn: () => Promise<T>): Promise<T> {
+		await this.acquire();
+		try {
+			return await fn();
+		} finally {
+			this.release();
+		}
+	}
+}
+
+// Limit concurrent OG image and GitHub API calls to avoid overwhelming the APIs
+const ogImageSemaphore = new Semaphore(3);
+const githubSemaphore = new Semaphore(5);
+
 export default async function ({
 	postMeta,
 	event
@@ -47,17 +89,23 @@ export default async function ({
 			template: 'maiertechPost',
 			title: postMeta.title
 		} as VcImageMeta;
-		ogImageUrl = await getOgImageUrl({ meta: ogImageMeta, apiKey: VIRALCARDS_API_KEY });
+		// Limit concurrent OG image API calls
+		ogImageUrl = await ogImageSemaphore.execute(() =>
+			getOgImageUrl({ meta: ogImageMeta, apiKey: VIRALCARDS_API_KEY })
+		);
 	}
 
 	// Resolve lastmodDate.
 	let lastmodDate: string | undefined = undefined;
-	const lastCommit = await getLastCommit({
-		owner: 'maiertech',
-		repo: 'website',
-		path: postMeta.filepath,
-		token: GITHUB_TOKEN
-	});
+	// Limit concurrent GitHub API calls
+	const lastCommit = await githubSemaphore.execute(() =>
+		getLastCommit({
+			owner: 'maiertech',
+			repo: 'website',
+			path: postMeta.filepath,
+			token: GITHUB_TOKEN
+		})
+	);
 
 	if (lastCommit) {
 		lastmodDate = lastCommit.commit.author?.date;

src/routes/+page.ts

@@ -1,13 +1,9 @@
 import type { NoteMeta, ResolvedPost } from '@maiertech/sveltekit-helpers';
 import type { PageLoad } from './$types';
 
-export const prerender = true;
+// export const prerender = true;
 
 export const load: PageLoad = async function ({ fetch }) {
-	// Read posts and notes.
-	// Do not reuse a `response` var to prevent this error:
-	// "Body is unusable: Body has already been read"
-
 	const notesResponse = await fetch('/api/notes/latest');
 	const notes = (await notesResponse.json()) as NoteMeta[];
 

src/routes/api/authors/[id]/+server.ts

@@ -4,6 +4,9 @@ import { error, json } from '@sveltejs/kit';
 import type { RequestHandler } from './$types';
 import authors from './authors';
 
+// We can't be sure that all routes are prerendered.
+export const prerender = 'auto';
+
 export const GET: RequestHandler = async ({ params }) => {
 	const id = params.id;
 	const author = resolve<AvatarMeta>(id, authors);

src/routes/api/notes/2025/+server.ts

@@ -14,7 +14,6 @@ import noteVercelProtectionBypass from '$notes/(2025)/vercel-deployment-protecti
 import { json } from '@sveltejs/kit';
 import type { RequestHandler } from './$types';
 
-// Needs to be set explicitly because we prerender endpoint `/sitemap.xml`.
 export const prerender = true;
 
 export const GET: RequestHandler = async () => {

src/routes/api/notes/all/+server.ts

@@ -2,7 +2,6 @@ import type { RequestHandler } from './$types';
 import { json } from '@sveltejs/kit';
 import type { NoteMeta } from '@maiertech/sveltekit-helpers';
 
-// Needs to be set explicitly because we prerender endpoint `/sitemap.xml`.
 export const prerender = true;
 
 // Return all notes.

src/routes/api/notes/latest/+server.ts

@@ -2,8 +2,7 @@ import type { RequestHandler } from './$types';
 import { json } from '@sveltejs/kit';
 import type { NoteMeta } from '@maiertech/sveltekit-helpers';
 
-// No need to set `export const prerender = true;`.
-// Prerendering is triggered by `/`, which uses this endpoint and iself is prerendered.
+export const prerender = true;
 
 // Return latest notes (up to 20).
 export const GET: RequestHandler = async ({ fetch }) => {

src/routes/api/posts/2021/+server.ts

@@ -6,8 +6,8 @@ import postMoveYourIdeToTheCloud from '$posts/(2021)/move-your-ide-to-the-cloud-
 import { json } from '@sveltejs/kit';
 import type { RequestHandler } from './$types';
 
-// Needs to be set explicitly because we prerender endpoint `/sitemap.xml`.
-export const prerender = true;
+// Nested prerendering breaks build on Railway.
+// export const prerender = true;
 
 export const GET: RequestHandler = async (event) => {
 	// Sort order: latest first.

src/routes/api/posts/2022/+server.ts

@@ -10,8 +10,8 @@ import postAtAndHashtagSymbols from '$posts/(2022)/using-the-at-and-hash-symbols
 import { json } from '@sveltejs/kit';
 import type { RequestHandler } from './$types';
 
-// Needs to be set explicitly because we prerender endpoint `/sitemap.xml`.
-export const prerender = true;
+// Nested prerendering breaks build on Railway.
+// export const prerender = true;
 
 export const GET: RequestHandler = async (event) => {
 	// Sort order: latest first.

src/routes/api/posts/2023/+server.ts

@@ -9,8 +9,8 @@ import postStackBlitzCodeflowBeta from '$posts/(2023)/is-stackblitz-codeflow-bet
 import { json } from '@sveltejs/kit';
 import type { RequestHandler } from './$types';
 
-// Needs to be set explicitly because we prerender endpoint `/sitemap.xml`.
-export const prerender = true;
+// Nested prerendering breaks build on Railway.
+// export const prerender = true;
 
 export const GET: RequestHandler = async (event) => {
 	// Sort order: latest first.

src/routes/api/posts/2024/+server.ts

@@ -3,8 +3,8 @@ import postCopilotContext from '$posts/(2024)/github-copilot-context/meta';
 import { json } from '@sveltejs/kit';
 import type { RequestHandler } from './$types';
 
-// Needs to be set explicitly because we prerender endpoint `/sitemap.xml`.
-export const prerender = true;
+// Nested prerendering breaks build on Railway.
+// export const prerender = true;
 
 export const GET: RequestHandler = async (event) => {
 	// Sort order: latest first.

src/routes/api/posts/2025/+server.ts

@@ -5,7 +5,8 @@ import postManagingEnvVarsWithVercel from '$posts/(2025)/managing-environment-va
 import { json } from '@sveltejs/kit';
 import type { RequestHandler } from './$types';
 
-export const prerender = true;
+// Nested prerendering breaks build on Railway.
+// export const prerender = true;
 
 export const GET: RequestHandler = async (event) => {
 	// Sort order: latest first.

src/routes/api/posts/all/+server.ts

@@ -2,8 +2,8 @@ import type { ResolvedPost } from '@maiertech/sveltekit-helpers';
 import { json } from '@sveltejs/kit';
 import type { RequestHandler } from './$types';
 
-// Needs to be set explicitly because we prerender endpoint `/sitemap.xml`.
-export const prerender = true;
+// Nested prerendering breaks build on Railway.
+// export const prerender = true;
 
 // Return all posts.
 export const GET: RequestHandler = async ({ fetch }) => {

src/routes/api/posts/latest/+server.ts

@@ -2,8 +2,8 @@ import type { ResolvedPost } from '@maiertech/sveltekit-helpers';
 import { json } from '@sveltejs/kit';
 import type { RequestHandler } from './$types';
 
-// No need to set `export const prerender = true;`.
-// Prerendering is triggered by `/`, which uses this endpoint and iself is prerendered.
+// Nested prerendering breaks build on Railway.
+// export const prerender = true;
 
 // Return latest posts (up to 10).
 export const GET: RequestHandler = async ({ fetch }) => {

src/routes/api/posts/rss/+server.ts

@@ -5,7 +5,8 @@ import type { ResolvedPost } from '@maiertech/sveltekit-helpers';
 import { json } from '@sveltejs/kit';
 import type { RequestHandler } from './$types';
 
-export const prerender = true;
+// Nested prerendering breaks build on Railway.
+// export const prerender = true;
 
 export const GET: RequestHandler = async ({ fetch }) => {
 	const response = await fetch('/api/posts/latest');

src/routes/api/tags/[id]/+server.ts

@@ -4,8 +4,7 @@ import { error, json } from '@sveltejs/kit';
 import type { RequestHandler } from './$types';
 import tags from './tags';
 
-// Include this endpoint into the manifest.
-// This ensures that dynamic calls for tags that have not been prerendered still work.
+// We can't be sure that all routes are prerendered.
 export const prerender = 'auto';
 
 export const GET: RequestHandler = async ({ params }) => {

src/routes/notes/rss.xml/+server.ts

@@ -2,7 +2,8 @@ import { ORIGIN } from '$env/static/private';
 import type { RssItem } from '$lib/types';
 import type { RequestHandler } from '@sveltejs/kit';
 
-export const prerender = true;
+// Prerendering turned off because notes endpoints are not prerendered.
+// export const prerender = true;
 
 export const GET: RequestHandler = async ({ fetch }) => {
 	const response = await fetch('/api/notes/rss');

src/routes/posts/rss.xml/+server.ts

@@ -2,7 +2,8 @@ import { ORIGIN } from '$env/static/private';
 import type { RssItem } from '$lib/types';
 import type { RequestHandler } from '@sveltejs/kit';
 
-export const prerender = true;
+// Prerendering turned off because posts endpoints are not prerendered.
+// export const prerender = true;
 
 export const GET: RequestHandler = async ({ fetch }) => {
 	const response = await fetch('/api/posts/rss');

src/routes/rss.xml/+server.ts

@@ -2,7 +2,8 @@ import { ORIGIN } from '$env/static/private';
 import type { RssItem } from '$lib/types';
 import type { RequestHandler } from '@sveltejs/kit';
 
-export const prerender = true;
+// Prerendering turned off because posts endpoints are not prerendered.
+// export const prerender = true;
 
 export const GET: RequestHandler = async ({ fetch }) => {
 	// Read posts and notes.

src/routes/sitemap.xml/+server.ts

@@ -2,7 +2,8 @@ import { ORIGIN } from '$env/static/private';
 import type { NoteMeta, ResolvedPost } from '@maiertech/sveltekit-helpers';
 import type { RequestHandler } from './$types';
 
-export const prerender = true;
+// Prerendering turned off because posts and notes endpoints are not prerendered.
+// export const prerender = true;
 
 export const GET: RequestHandler = async ({ fetch }) => {
 	// Fetch posts. `/api/posts/all` includes `lastmodDate`.