The route a grid's exports download from.

defmodule MyAppWeb.Router do
  use MyAppWeb, :router
  import Masu.Router

  scope "/" do
    pipe_through [:browser, :require_authenticated_user]

    live "/orders", OrdersLive
    masu_exports "/masu/exports"
  end
end

A grid with export gives the browser a link to this route, with a token: encrypted with the endpoint's secret_key_base, good for one download, for five minutes, and from the LiveView that made it while it runs. Put it in a scope that requires the person to be signed in, as the grid's LiveView does: the token proves the grid made the export, the pipeline that the person is still who they were.

The path goes through the scopes it is in, and the endpoint's script_name: a grid finds it in the router of its LiveView.

With the app on several nodes, a download must reach a node that is connected to the LiveView's (distributed Erlang, as Phoenix.PubSub has it).