application.ex

defmodule GoogleStorage.Application do

  # ...

  @impl true
  def start(_type, _args) do
    producer_module = Application.get_env(:google_storage, :producer_module)

    children = [
      {GoogleStorage.Pipeline, [producer_module: producer_module]}
    ]

    opts = [strategy: :one_for_one, name: GoogleStorage.Supervisor]
    Supervisor.start_link(children, opts)
  end
end