doc: Add RSS generation

doc/_support/converter/bin/process-doc

@@ -27,6 +27,10 @@ Processor::Sitemap
   .new(Processor::Page.get_sitemap)
   .generate()
 
+Processor::RSS
+  .new(Processor::Page.get_sitemap)
+  .generate()
+
 # Copying the styles, as needed
 if $options["styles_dir"] then
   puts "[s] Copying styles"

doc/_support/converter/lib/processor.rb

@@ -5,5 +5,6 @@ require_relative "processor/article"
 require_relative "processor/footer"
 require_relative "processor/header"
 require_relative "processor/page"
+require_relative "processor/rss"
 require_relative "processor/sitemap"
 require_relative "processor/toc"

doc/_support/converter/lib/processor/rss.rb

@@ -0,0 +1,54 @@
+require "date"
+
+module Processor
+  # TODO: common base class or mixin with Sitemap
+  class RSS
+    Path = /^news\//
+    include ERB::Util
+
+    def to_rss(entries)
+      entry_template = ERB.new(File.read(File.join($options["root"], "_support/rss_entry.xml.erb")))
+      item_nodes = entries.map do |entry|
+        entry_template.result(binding)
+      end
+
+      document_template = ERB.new(File.read(File.join($options["root"], "_support/rss.xml.erb")))
+      document_template.result(binding)
+    end
+
+    attr_reader :sitemap
+
+    def strip_unneecessary(contents)
+      contents
+        .gsub(/<header.*<\/header>/m, "")
+        .gsub(/<footer.*<\/footer>/m, "")
+    end
+
+    def full_url(path)
+      [
+        "https://mobile.nixos.org",
+        path
+      ].join("/")
+    end
+
+    def initialize(sitemap)
+    end
+
+    def generate()
+      puts "[S] Generating sitemap..."
+      entries = Article.get_article_paths().map do |filename|
+        entry = Article.new(filename)
+        {
+          title: entry.title,
+          url: full_url(entry.out_path),
+          date: entry.date,
+          contents: strip_unneecessary(entry.output),
+        }
+      end
+
+      File.open(File.join($options["output_dir"], "index.xml"), "w") do |file|
+        file.write(to_rss(entries))
+      end
+    end
+  end
+end

doc/_support/rss.xml.erb

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom">
+  <channel>
+    <title>Mobile NixOS news</title>
+    <description>RSS feed for Mobile NixOS</description>
+    <lastBuildDate><%= entries.first[:date].rfc822 %></lastBuildDate>
+    <link>https://mobile.nixos.org/</link>
+    <atom:link href="https://mobile.nixos.org/index.xml" rel="self" type="application/rss+xml"/>
+<%= item_nodes.join("\n") %>
+  </channel>
+</rss>

doc/_support/rss_entry.xml.erb

@@ -0,0 +1,9 @@
+    <item>
+      <title><%= html_escape(entry[:title]) %></title>
+      <pubDate><%= html_escape(entry[:date].rfc822) %></pubDate>
+      <link><%= html_escape(entry[:url]) %></link>
+      <guid><%= html_escape(entry[:url]) %></guid>
+      <description>
+<%= html_escape(entry[:contents]) %>
+      </description>
+    </item>