Encoding with Views

comment_view.ex

defmodule MyApp.CommentView do                                                                                                                                                                  
  use MyApp.Web, :view
  @attributes ~W(id name inserted_at)
  
  def render("show.json", data: data) when is_list(data) do 
    for c <- data do
      render("show.json", data: data)
    end
  end
  
  def render("show.json", data: data) do
    data
    |> Map.take(@attributes)
    |> Map.put(:user, UserView.render('show_lite.json', data: data.user))
  end
end

mymodel_view.ex

defmodule MyApp.MyModelView do                                                                                                                                                                  
  use MyApp.Web, :view
  @attributes ~W(id body title inserted_at)
  
  def render("show.json", data: data)
    data
    |> Map.take(@attributes)
    |> Map.update!(:title, &String.capitalize)
    |> Map.put(:user, UserView.render("show.json", data: data.user)
    |> Map.put(:comments, CommentView.render("show.json", data: data.comments))
  end
end

user_view.ex

defmodule MyApp.UserView do                                                                                                                                                                  
  use MyApp.Web, :view
  @attributes ~W(id name inserted_at)
  
  def render("show.json", data: data)    
    render("show_lite.json", data: data)
    |> Map.put(:image, ImageView.render("show.json", data: data.image))
  end
  
  def render("show_lite.json", data: data)    
    data
    |> Map.take(@attributes)
  end
end