Wicked PDF Fonts to base64

example.scss

@font-face {
  font-family: 'Glyphicons Halflings';
  src: url(asset_base64('admin/fonts/glyphicons-halflings-regular.eot'));

  src:  url(asset_base64('admin/fonts/glyphicons-halflings-regular.eot')) format('embedded-opentype'),
        url(asset_base64('admin/fonts/glyphicons-halflings-regular.woff2')) format('woff2'),
        url(asset_base64('admin/fonts/glyphicons-halflings-regular.woff')) format('woff'),
        url(asset_base64('admin/fonts/glyphicons-halflings-regular.ttf')) format('truetype'),
        url(asset_base64('admin/fonts/glyphicons-halflings-regular.svg')) format('svg');
}

sprockets.rb

require 'sass'

module Sprockets::SassFunctions
  def asset_base64(path)
    asset = Rails.application.assets.find_asset(path.value)
    throw "Could not find asset '#{path}'" if asset.nil?
    base64 = Base64.encode64(asset.to_s).gsub(/\s+/, "")
    code = "data:#{asset.content_type};base64,#{Rack::Utils.escape(base64)}"
     ::Sass::Script::String.new(code, :string)
  end
end