Use a custom helper in Middleman Frontmatter

Question

my Middleman structure looks like this:

source/
  blog/
    post-one.md
    post-two.md
  blog.erb
  index.md

my config.rb defines this helper:

helpers do
  TOP_LEVEL_DIR = Dir.pwd

  def posts
    files = Dir["#{TOP_LEVEL_DIR}/source/blog/*"]

    files.map do |file|
      created_at = `git log --follow --date=short --pretty=format:%ad --diff-filter=A -- #{file}`
      basename = File.basename(file).split('.')[0]

      {
        date: created_at,
        link: '/blog/' + basename,
        title: basename.gsub('-', ' ').capitalize
      }
    end
  end
end

And my blog.erb looks like this:

<ul>
  <% posts.each do |post| %>
    <li><%=post[:date]%>: <%= link_to post[:title], post[:link] %></li>
  <% end %>
</ul>

This works really well for me, but I'm missing one thing. I want to display the created_at metadata that I've defined in my custom helper in the layouts for post-one and post-two.

Usually this is done by defining Frontmatter, but I don't want to manually input the dates of each post when they are available in git.

So I need a way to define a custom helper that allows me to access the current_page meta data. Or some other way to pass in the metadata I'm manually creating in the posts helper into the layout.

Answer 1

This was much more straightforward than I thought it would be. current_page is available in helpers, so I can use it directly in my helper like this in config.rb:

helpers do
  def created_at
    # `git log --follow --date=short --pretty=format:%ad --diff-filter=A -- #{current_page.source_file}`
  end
end