Monthly Atom feed of Jekyll posts

monthlyfeed.rb

module Jekyll
  class MonthlyFeed < Page
    include Convertible

    attr_accessor :site, :pager, :name, :ext, :basename, :dir, :data, :content, :output

    # Initialize new ArchivePage
    # +site+ is the Site
    # +month+ is the month
    # +posts+ is the list of posts for the month
    #
    # Returns <ArchivePage>
    def initialize(site, feeddata)
      @site = site
      @feeddata = feeddata
      self.ext = '.xml'
      self.basename = 'monthlyfeed'
      self.content = <<-EOS
{% assign months = "January,February,March,April,May,June,July,August,September,October,November,December" | split: "," %}
{% for month in page.feeddata %}
  {% assign thisdate = month[0] | split: '/' %}
  {% assign thisyear = thisdate[0] %}
  {% assign monthindex = thisdate[1] | minus: 1 %}
  {% assign thismonth = months[monthindex] %}
  {% assign currentmonth = site.time | date: "%Y/%m" %}
  {% unless month[0] == currentmonth %}
    <entry>
      <title>Birdblog posts from {{ thismonth }} {{ thisyear }}</title>
      <link href="{{ site.url }}{{ site.baseurl }}/archive/{{ thisyear}}/{{ thisdate[1] }}/index.html"/>
      <id>{{ site.url }}{{ site.baseurl }}/archive/{{ thisyear}}/{{ thisdate[1] }}/index.html</id>
      <updated>{{ month[1].last.date | date_to_xmlschema }}</updated>
      <summary>Birdblog posts for {{ thismonth }} {{ thisyear }}.</summary>
      <content type = "html">{% capture content %}
<p>This month’s posts from my <a href="http://birdblog.bighairydave.com/">Bird Blog:</a>
<ul>{% for post in month[1] %}
<li>{{ post.date | date: "%B %-d:"}} <a href="{{ post.url | prepend: site.url }}">{{ post.title }}</a></li>
{% endfor %}</ul>{% endcapture %}
{{ content | xml_escape }}
      </content>
    </entry>
  {% endunless %}
{% endfor %}
EOS
      self.data = {
        'layout' => 'feed',
        'type' => 'archive',
        'title' => "Birdblog Monthly Feed",
        'feeddata' => @feeddata
      }
    end

    # Add any necessary layouts
    # +layouts+ is a Hash of {"name" => "layout"}
    # +site_payload+ is the site payload hash
    #
    # Returns nothing
    def render(layouts, site_payload)
      payload = {
        "page" => self.to_liquid,
        "paginator" => pager.to_liquid
      }
      merged_payload = Utils.deep_merge_hashes(site_payload, payload)
      do_layout(merged_payload, layouts)
    end

    def url
      File.join("/", "monthlyfeed.xml")
    end
    
    def to_liquid
      Utils.deep_merge_hashes(self.data, {
                                           "url" => self.url,
                                           "content" => self.content
                                         })
    end

    # Write the generated page file to the destination directory.
    # +dest_prefix+ is the String path to the destination dir
    # +dest_suffix+ is a suffix path to the destination dir
    #
    # Returns nothing

    def write(dest_prefix, dest_suffix = nil)
      dest = dest_prefix
      dest = File.join(dest, dest_suffix) if dest_suffix
      FileUtils.mkdir_p(dest)
      # The url needs to be unescaped in order to preserve the
      # correct filename
      path = File.join(dest, CGI.unescape(self.url))
      FileUtils.mkdir_p(File.dirname(path))
      File.open(path, 'w') do |f|
        f.write(self.output)
      end
    end

    def html?
      true
    end
  end
end