Sorry for the late reply!

The option to set body read timeouts is actually set as part of the Plug.Conn.read_body/2 call; see Plug.Conn — Plug v1.20.2 (specifically the read_timeout parameter) for details.

The read_timeout parameter as you’re passing it above (note that the options field has recently changed to thousand_island_options) is concerned with read timeouts for operations not otherwise set via the Plug.Conn API, such as header reading, HTTP/2 frame reading, etc.

I just configured it like this:

  config :my_app, MyAppWeb.Endpoint,
    url: [host: host, port: 443, scheme: "https"],
    http: [
      ip: {0, 0, 0, 0, 0, 0, 0, 0},
      port: port,
      thousand_island_options: [
        # Wait 60s for the client to complete the connection/upload before forcibly shutting it (Default: 15s)
        shutdown_timeout: 60_000
      ]
    ],
    secret_key_base: secret_key_base