From 7ab3f4e6fa4ebde9e1e7fe81d3a84b0d48732ab3 Mon Sep 17 00:00:00 2001
From: Daniel Masterson <daniel.masterson@novadawnstudios.co.uk>
Date: Sun, 25 Aug 2024 19:59:19 +0100
Subject: [PATCH] feat: Limit RSS Feed to return a maximum of 20 items

---
 src/app/feed.xml/route.ts | 57 +++++++++++++++++++++++++++++----------
 1 file changed, 43 insertions(+), 14 deletions(-)

diff --git a/src/app/feed.xml/route.ts b/src/app/feed.xml/route.ts
index c1fe957..4d761f1 100644
--- a/src/app/feed.xml/route.ts
+++ b/src/app/feed.xml/route.ts
@@ -1,9 +1,23 @@
 import { Feed } from "feed";
-import { releaseNoteIsAlpha, releaseNotes } from "@/lib/release-notes";
+import { releaseNotes } from "@/lib/release-notes";
 import type { ReleaseNote } from "@/lib/release-notes";
 
+// Force feed.xml to be cached as static and remain constant for the lifetime of the current site build.
+// The supplied releaseNotes array is constant per build, so this will always be the latest release notes.
+export const dynamic = "force-static";
+
+/** The default number of entries to include in the RSS feed. */
+const RSS_ENTRY_LIMIT = 20;
+
+/**
+ * Handles the GET request for the `feed.xml` endpoint.
+ * @returns The RSS feed for the Zen Browser release notes.
+ */
 export async function GET() {
-    releaseNotes[0].date
+    // Just in case the release notes array is empty for whatever reason.
+    const latestDate = releaseNotes.length > 0
+        ? formatRssDate(releaseNotes[0].date)
+        : new Date();
 
     const feed = new Feed({
         id: "https://www.zen-browser.app/release-notes",
@@ -13,10 +27,10 @@ export async function GET() {
         language: "en",
         favicon: "https://www.zen-browser.app/favicon.ico",
         copyright: `Zen Browser © ${new Date().getFullYear()} - Made with ❤️ by the Zen team.`,
-        updated: formatRssDate(releaseNotes[0].date),
+        updated: latestDate,
     });
 
-    for (const releaseNote of releaseNotes) {
+    for (const releaseNote of releaseNotes.slice(0, RSS_ENTRY_LIMIT)) {
         feed.addItem({
             title: `Release notes for version ${releaseNote.version}`,
             id: `https://www.zen-browser.app/release-notes/${releaseNote.version}`,
@@ -34,23 +48,38 @@ export async function GET() {
     });
 }
 
-function formatRssDate(date: string) {
-    // NOTE: This is assuming the format day/month/year. If release notes change to ISO format, this will need to be updated.
-    const splitDate = date.split("/");
-    const year = Number(splitDate[2]);
-    const month = Number(splitDate[1]) - 1;
+/**
+ * Formats a date string in the format day/month/year. 
+ * 
+ * Note: If release notes change to ISO format, this will need to be updated.
+ * @param dateStr The date string to format.
+ * @returns The passed in date string as a Date object.
+ */
+function formatRssDate(dateStr: string) {
+    const splitDate = dateStr.split("/");
+    if (splitDate.length !== 3) {
+        throw new Error("Invalid date format");
+    }
+
     const day = Number(splitDate[0]);
+    const month = Number(splitDate[1]) - 1;
+    const year = Number(splitDate[2]);
     return new Date(year, month, day);
 }
 
+/**
+ * Formats the release note entry for use as the content of the RSS feed.
+ * @param releaseNote The release note to format.
+ * @returns The formatted release note as a HTML string.
+ */
 function formatReleaseNote(releaseNote: ReleaseNote) {
     let content = "<p>If you encounter any issues, please report them on <a href=\"https://github.com/zen-browser/desktop/issues/\">the issues page</a>. Thanks everyone for your feedback! ❤️</p>";
 
-    if(releaseNote.extra) {
+    if (releaseNote.extra) {
         content += `<p>${releaseNote.extra.replace(/(\n)/g, "<br />")}</p>`
     }
 
-    if(releaseNote.breakingChanges) {
+    if (releaseNote.breakingChanges) {
         content += `<h2>⚠️ Breaking changes</h2>`
         content += `<ul>`
         for (const breakingChange of releaseNote.breakingChanges) {
@@ -59,7 +88,7 @@ function formatReleaseNote(releaseNote: ReleaseNote) {
         content += `</ul>`
     }
 
-    if(releaseNote.features) {
+    if (releaseNote.features) {
         content += `<h2>⭐ Features</h2>`
         content += `<ul>`
         for (const feature of releaseNote.features) {
@@ -68,7 +97,7 @@ function formatReleaseNote(releaseNote: ReleaseNote) {
         content += `</ul>`
     }
 
-    if(releaseNote.fixes) {
+    if (releaseNote.fixes) {
         content += `<h2>✓ Fixes</h2>`
         content += `<ul>`
         for (const fix of releaseNote.fixes) {
@@ -78,4 +107,4 @@ function formatReleaseNote(releaseNote: ReleaseNote) {
     }
 
     return content;
-}
\ No newline at end of file
+}