refactor: Add series filter on `getPosts`

src/lib/posts.ts

@@ -15,7 +15,8 @@ export function transformPostMeta(metadata: PostMetadata, slug: string) : Post {
 	};
 }
 
-export async function getPosts(tag: string | null = null) : Promise<Post[]> {
+// Generates a list of all posts filtering by tags and series
+export async function getPosts(filter: { tag?: string, series?: string }) : Promise<Post[]> {
 	const allPostFiles = import.meta.glob('$content/post/*.md');
 	const iterablePostFiles = Object.entries(allPostFiles);
 
@@ -27,8 +28,10 @@ export async function getPosts(tag: string | null = null) : Promise<Post[]> {
 			return transformPostMeta(metadata, slug);
 		})
 	);
-	if (tag)
+	if (filter?.tag)
-		posts = posts.filter(post => post.tags.includes(tag))
+		posts = posts.filter(post => post.tags.includes(filter.tag!))
+	if (filter?.series)
+		posts = posts.filter(post => post.series?.includes(filter.series!) ?? false)
 
 	posts.sort((post1, post2) => {
 		const date1: Date = post1.date;

src/routes/tag/[slug]/+page.ts

@@ -2,7 +2,7 @@ import type { PageLoad } from './$types';
 import { getPosts } from '$lib/posts';
 
 export const load: PageLoad = async ({ params }) => {
-	const posts = await getPosts(params.slug);
+	const posts = await getPosts({ tag: params.slug });
 	return {
 		name: params.slug,
 		posts,