Determines whether this plugin is active.

    This plugin is only active if TensorBoard sampled any text summaries.

    Returns:
      Whether this plugin is active.

def is_active(self):
    """Determines whether this plugin is active.

    This plugin is only active if TensorBoard sampled any text summaries.

    Returns:
      Whether this plugin is active.
    """
    if not self._multiplexer:
      return False

    if self._index_cached is not None:
      # If we already have computed the index, use it to determine whether
      # the plugin should be active, and if so, return immediately.
      if any(self._index_cached.values()):
        return True

    if self._multiplexer.PluginRunToTagToContent(metadata.PLUGIN_NAME):
      # Text data is present in the multiplexer. No need to further check for
      # data stored via the outdated plugin assets method.
      return True

    # We haven't conclusively determined if the plugin should be active. Launch
    # a thread to compute index_impl() and return False to avoid blocking.
    self._maybe_launch_index_impl_thread()

    return False