code: def get_archiver_index(config, archiver):
      
      root = pathlib.Path(config.cache_path) / archiver
      with (root / "index.json").open("r") as index_f:
          index = json.load(index_f)
      return index
docs: Get the contents of the archiver index file.
  
      :param config: The configuration
      :type  config: :class:`wily.config.WilyConfig`
  
      :param archiver: The name of the archiver type (e.g. 'git')
      :type  archiver: ``str``
      
      :return: The index data
      :rtype: ``dict``