Categories extension for lambdapad

categories.exs

@doc """
A set of transformations to help us work with categories.
This extension requires the following configuration entries:

[categories.desarrollo]
class = "cat-1"
link = "category/desarrollo"

[categories.historias]
class = "cat-2"
link = "category/historias"

There are two different transformations in this file:

- categories: it generates a map where the key is the category and the content is the number of posts in addition of the configuration options. You can use this in pages or widgets with transform_config.

- category class: sets the category_class key based on the configuration and what's defined in the category field for each post. You can use this in pages or widgets with transforma_item.

"""

transform "categories" do
  set on: :config
  set run: fn(config, posts) ->
    num_posts = Enum.reduce(posts, %{}, & Map.update(&2, &1["category"], 1, fn i -> i + 1 end))
    categories =
      for {name, data} <- config["categories"], into: %{} do
        {name, Map.put(data, "num_posts", num_posts[name])}
      end
      |> Enum.sort_by(fn {_, data} -> data["class"] || "000" end)

    Map.put(config, "_categories", categories)
  end
end

transform "category class" do
  set on: :item
  set run: fn(post, config) ->
    category_name = post["category"]
    class = config["categories"][category_name]["class"] || ""
    Map.put(post, "category_class", class)
  end
end