fetch

# File activestorage/lib/active_storage/service/registry.rb, line 10
    def fetch(name)
      services.fetch(name.to_sym) do |key|
        if configurations.include?(key)
          services[key] = configurator.build(key)
        else
          if block_given?
            yield key
          else
            raise KeyError, "Missing configuration for the #{key} Active Storage service. "                "Configurations available for the #{configurations.keys.to_sentence} services."
          end
        end
      end
    end