feat: add feeds for the blog and vulnerabilities (#1867)

This adds two new feeds to the site: `feed.xml` includes all blog posts,
and `vulnerabilities.xml` includes all posts tagged with
`vulnerabilities`.

Resolves #1763

---------

Co-authored-by: Sebastian Beltran <bjohansebas@gmail.com>

_includes/feed-entry.xml

@@ -0,0 +1,17 @@
+{%- assign entry = include.entry -%}
+<entry>
+  <id>{{ site.url }}{{ entry.url }}</id>
+  <link href="{{ site.url }}{{ entry.url }}" rel="alternate" type="text/html" />
+  <title type="text">{{ entry.title }}</title>
+  {%- if entry.author %}
+  <author>
+    <name>{{ entry.author }}</name>
+  </author>
+  {%- endif %}
+  <published>{{ entry.date | date_to_xmlschema }}</published>
+  <updated>{{ entry.last_modified_at | default: post.date | date_to_xmlschema }}</updated>
+  {%- for tag in post.tags %}
+  <category term="{{ tag | xml_escape }}" />
+  {%- endfor %}
+  <content type="html"><![CDATA[ <a href="{{ site.url }}{{ entry.url }}">Read {{ entry.title }}</a> ]]></content>
+</entry>

_includes/head.html

@@ -47,4 +47,6 @@
     <script data-cfasync="false" defer src="/js/menu.js"></script>
     <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/docsearch.js@2/dist/cdn/docsearch.min.css" />
 
+    <link rel="alternate" type="application/atom+xml" href="/feed.xml" title="Express Blog" />
+    <link rel="alternate" type="application/atom+xml" href="/vulnerabilities.xml" title="Express Vulnerabilities" />
 </head>

_layouts/feed.xml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<feed xmlns="http://www.w3.org/2005/Atom" xml:lang="en">
+  <title type="text">{{ page.title }}</title>
+  <link href="{{ site.url }}{{ page.html_url }}" rel="alternate" type="text/html" />
+  <link href="{{ site.url }}{{ page.url }}" rel="self" type="application/atom+xml" />
+  <id>{{ site.url }}{{ page.url }}</id>
+  <rights>Copyright The Express Contributors</rights>
+  <updated>{{ site.time | date_to_xmlschema }}</updated>
+  {{ content }}
+</feed>

_posts/2024-09-29-security-releases.md

@@ -1,7 +1,7 @@
 ---
 title: September 2024 Security Releases
 description: Security releases for Express, body-parser, send, serve-static, and path-to-regexp have been published. We recommend that all users upgrade as soon as possible.
-tags: security, vulnerabilities
+tags: security vulnerabilities
 author: Ulises Gascón
 ---
 

_posts/2024-10-01-HeroDevs-partnership-announcement.md

@@ -1,7 +1,7 @@
 ---
 title: Express Never Ending Support Launched by HeroDevs and Express.js
 description: The Express.js team is pleased to announce a partnership with HeroDevs to launch Express Never-Ending Support (NES), providing long-term support for applications built with legacy Express. This collaboration ensures that developers relying on older versions of the framework will continue to receive critical security and compatibility updates, allowing them to maintain and scale their applications securely, even after the framework's official end-of-life.
-tags: partnerships, announcements
+tags: partnerships announcements
 author: Express Technical Committee
 ---
 

_posts/2024-10-22-security-audit-milestone-achievement.md

@@ -1,6 +1,6 @@
 ---
 title: "Express.js Security Audit: A Milestone Achievement"
-tags: security, audit, releases
+tags: security audit releases
 author: Express Technical Committee
 description: Celebrating the successful completion of the Express.js security audit conducted by Ada Logics and facilitated by OSTIF.
 ---

_posts/2025-01-09-rewind-2024-triumphs-and-2025-vision.md

@@ -1,6 +1,6 @@
 ---
 title: "A New Chapter for Express.js: Triumphs of 2024 and an ambitious 2025"
-tags: news, rewind, 2024
+tags: news rewind 2024
 author: Express Technical Committee
 description: Explore the transformative journey of Express.js in 2024, marked by governance improvements, the long-awaited release of Express 5.0, and heightened security measures. Look into the ambitious plans for 2025, including performance optimizations, scoped packages, and a bold roadmap for sustained growth in the Node.js ecosystem.
 ---

_posts/2025-03-31-v5-1-latest-release.md

@@ -1,6 +1,6 @@
 ---
 title: "Express@5.1.0: Now the Default on npm with LTS Timeline"
-tags: news, release 
+tags: news release
 author: Express Technical Committee
 description: Express 5.1.0 is now the default on npm, and we're introducing an official LTS schedule for the v4 and v5 release lines.
 ---

feed.xml

@@ -0,0 +1,10 @@
+---
+layout: feed
+sitemap: false
+title: Express Blog
+html_url: /en/blog/posts.html
+---
+{% assign posts = site.posts | sort: "date" | reverse %}
+{% for post in posts %}
+{% include feed-entry.xml entry=post %}
+{% endfor %}

vulnerabilities.xml

@@ -0,0 +1,10 @@
+---
+layout: feed
+sitemap: false
+title: Express Vulnerabilities
+html_url: /en/blog/posts.html
+---
+{% assign posts = site.posts | sort: "date" | reverse %}
+{% for post in posts %}
+{% if post.tags contains "vulnerabilities" %}{% include feed-entry.xml entry=post %}{% endif %}
+{% endfor %}