feat: publish scheduled posts on their pubDate with a daily build

src/pages/blog.astro

@@ -1,6 +1,7 @@
 ---
 import type { CollectionEntry } from "astro:content";
 import { getCollection } from "astro:content";
+import { isPublished } from "../utils/posts";
 import { Image } from "astro:assets";
 import Footer from "../components/Footer.astro";
 import Navbar from "../components/Navbar.astro";
@@ -11,7 +12,7 @@ type BlogPost = CollectionEntry<"blog">;
 
 const allPosts: BlogPost[] = await getCollection("blog");
 const sortedPosts: BlogPost[] = allPosts
-	.filter((post: BlogPost) => !post.data.draft)
+	.filter((post: BlogPost) => isPublished(post))
 	.sort((a: BlogPost, b: BlogPost) => b.data.pubDate.valueOf() - a.data.pubDate.valueOf());
 
 const allTags: Record<string, number> = sortedPosts.reduce(

src/pages/blog/[slug].astro

@@ -1,6 +1,7 @@
 ---
 import type { CollectionEntry } from "astro:content";
 import { getCollection } from "astro:content";
+import { isPublished } from "../../utils/posts";
 import { Image } from "astro:assets";
 import BaseLayout from "../../layouts/BaseLayout.astro";
 import Navbar from "../../components/Navbar.astro";
@@ -15,7 +16,7 @@ type BlogPost = CollectionEntry<"blog">;
 
 export async function getStaticPaths() {
 	const blogEntries: BlogPost[] = await getCollection("blog");
-	return blogEntries.map((entry: BlogPost) => ({
+	return blogEntries.filter((entry: BlogPost) => isPublished(entry)).map((entry: BlogPost) => ({
 		params: { slug: entry.slug },
 		props: { entry },
 	}));

src/pages/blog/tag/[tag].astro

@@ -1,6 +1,7 @@
 ---
 import type { CollectionEntry } from "astro:content";
 import { getCollection } from "astro:content";
+import { isPublished } from "../../../utils/posts";
 import { Image } from "astro:assets";
 import Footer from "../../../components/Footer.astro";
 import Navbar from "../../../components/Navbar.astro";
@@ -10,7 +11,7 @@ type BlogPost = CollectionEntry<"blog">;
 
 export async function getStaticPaths() {
 	const allPosts: BlogPost[] = await getCollection("blog");
-	const publishedPosts: BlogPost[] = allPosts.filter((post: BlogPost) => !post.data.draft);
+	const publishedPosts: BlogPost[] = allPosts.filter((post: BlogPost) => isPublished(post));
 
 	const allTags = new Set<string>();
 	publishedPosts.forEach((post: BlogPost) => {

src/pages/rss.xml.ts

@@ -1,11 +1,12 @@
 import rss from "@astrojs/rss";
 import { getCollection } from "astro:content";
+import { isPublished } from "../utils/posts";
 import type { APIContext } from "astro";
 
 export async function GET(context: APIContext) {
 	const blog = await getCollection("blog");
 	const publishedPosts = blog
-		.filter((post) => !post.data.draft)
+		.filter((post) => isPublished(post))
 		.sort((a, b) => b.data.pubDate.valueOf() - a.data.pubDate.valueOf());
 
 	return rss({

src/utils/posts.ts

@@ -0,0 +1,13 @@
+import type { CollectionEntry } from "astro:content";
+
+type BlogPost = CollectionEntry<"blog">;
+
+// A post with a future pubDate stays in the repo but is left out of the build
+// until that day (Rome calendar day, not UTC): the scheduled CI build publishes
+// it. `astro dev` shows everything so scheduled posts can be previewed.
+export function isPublished(post: BlogPost, now: Date = new Date()): boolean {
+	if (post.data.draft) return false;
+	if (import.meta.env.DEV) return true;
+	const today = new Intl.DateTimeFormat("en-CA", { timeZone: "Europe/Rome" }).format(now);
+	return post.data.pubDate.toISOString().slice(0, 10) <= today;
+}