Overhaul sitemap

[maiertech]

• I turned off the sitemap temporarily while working on Refactor posts.ts #612.
• Before overhauling the sitemap, I double-checked how other devs do sitemaps with SvelteKit.

Sitemap overview

• Official docs: very little guidance.
• WebJeda's post: goes beyond the official docs and explains how to read items for the sitemap from an API or import glob Markdown files from the file system.
• Okupter's post: should have done more research on what Google actually uses.
• Scott Spence's post: Outdated post (but he says so).
• There is an open issue with a great discussion on the best approach: sitemap.xml sveltejs/kit#1142.

Do I need a sitemap?

• Probably not! https://developers.google.com/search/docs/crawling-indexing/sitemaps/overview
• It may be useful if you don't link all your content.
• Does a sitemap even make sense? sitemap.xml sveltejs/kit#1142 (comment)

Google specifics

https://developers.google.com/search/docs/crawling-indexing/sitemaps/build-sitemap#xml

• You can submit an RSS feed as a sitemap.
• Google ignores priority and changefreq.
• Do you need sitemap extensions? Probably not.

Alternative

This comment proposes an alternative when using adapter-static: https://github.com/bartholomej/svelte-sitemap

• Scans routes in build and creates build/sitemap.xml.
• Uses the postbuild hook in package.json.

Approach

• Build on endpoints I already have, e.g., posts.json, categories.json, and tags.json.
• Add additional information to these endpoints.
• Add certain static pages manually.
• Add static paths as an array.