@callback child_spec(name :: atom(), opts :: Keyword.t()) :: false | map()

@callback commit(name :: atom(), Kvasir.Topic.t(), Kvasir.Event.t()) ::
  {:ok, Kvasir.Event.t()} | {:error, atom()}

@callback contains?(name :: atom(), Kvasir.topic(), Kvasir.Offset.t()) ::
  :maybe | true | false

@callback generate_dedicated_publisher(
  name :: atom(),
  target :: module(),
  Kvasir.Topic.t(),
  opts :: Keyword.t()
) :: :ok | {:error, atom()}

@callback listen(
  name :: atom(),
  Kvasir.topic(),
  callback :: (Kvasir.Event.t() -> :ok | {:error, reason :: atom()}),
  opts :: Kvasir.EventSource.stream_opts()
) :: :ok | {:error, atom()}

@callback stream(name :: atom(), Kvasir.topic(), opts :: Kvasir.EventSource.stream_opts()) ::
  {:ok, Stream.t()} | {:error, atom()}

@callback subscribe(
  name :: atom(),
  Kvasir.topic(),
  opts :: Kvasir.EventSource.stream_opts()
) ::
  {:ok, pid()} | {:error, atom()}