feat: update implementation of RSS feeds

Adds a new filter `convertRelativeLinks` that converts any relative link
to an absolute path
Adds an XML transform to minify the final output for smaller filesizes
Updates some data in meta
Adds a new macro for generating an RSS feed

config/filters/index.js

@@ -4,6 +4,8 @@ import advancedFormat from "dayjs/plugin/advancedFormat.js";
 
 import pluralizeBase from "pluralize";
 
+import { JSDOM } from "jsdom";
+
 export const keys = Object.keys;
 export const values = Object.values;
 export const entries = Object.entries;
@@ -12,6 +14,7 @@ dayjs.extend(utc);
 dayjs.extend(advancedFormat);
 
 export const formatDate = (date, format) => dayjs.utc(date).format(format);
+export const formatAsUTCString = (date) => new Date(date).toUTCString();
 
 export const organizeByDate = (collection) => {
   const collectionByDate = {};
@@ -101,3 +104,29 @@ export const isOld = (dateArg) => {
 
   return diffInYears >= 2;
 };
+
+// From coryd.dev
+// https://www.coryd.dev/posts/2025/generating-absolute-urls-in-my-rss-feeds/
+export const convertRelativeLinks = (htmlContent, url) => {
+  if (!htmlContent || !url) return htmlContent;
+
+  const dom = new JSDOM(htmlContent);
+  const document = dom.window.document;
+
+  document.querySelectorAll("a[href]").forEach((link) => {
+    let href = link.getAttribute("href");
+
+    if (href.startsWith("#")) {
+      link.remove();
+      return;
+    }
+
+    if (!href.startsWith("http://") && !href.startsWith("https://"))
+      link.setAttribute(
+        "href",
+        `${url.replace(/\/$/, "")}/${href.replace(/^\/+/, "")}`,
+      );
+  });
+
+  return document.body.innerHTML;
+};

config/transforms/xml-config.js

@@ -0,0 +1,12 @@
+import minifyXML from "minify-xml";
+
+export default function (eleventyConfig) {
+  eleventyConfig.addTransform("xml-minify", (content, path) => {
+    if (path && path.endsWith(".xml")) {
+      return minifyXML(content, {
+        shortenNamespaces: false,
+      });
+    }
+    return content;
+  });
+}