remote-snippets.rb

require 'open-uri'

class RemoteSnippets
  class << self
    def get(key)
      url = @mappings[key]
      open(url).read
    end

    def register(key, url)
      @mappings ||= {}
      @mappings[key] = url
    end

    def []=(key, url)
      register key, url
    end

    def [](key)
      get key
    end
  end
end

# usage:
# in an initializer create some mappings:
# RemoteSnippets.register("header", "http://www.propublica.org/rails/header")
#
# or
#
# RemoteSnippets["header"] = "http://www.propublica.org/rails/header"
#
# and then in templates use either:
#
# RemoteSnippets.get("header")
#
# or
#
# RemoteSnippets["header"]