What the correct way to Phoenix send a new generated file (non text, example gz).

I’m trying with full path (with application dir) or regular path, neither are working.
Tried with File.read! also.

conn
|> put_resp_content_type("application/gzip")
|> put_resp_header("content-disposition", "attachment; filename=#{filename}.gz")
|> send_file(200, full_path)

I can send text files with this:

conn
|> put_resp_content_type(filetype)
|> put_resp_header("content-disposition", "attachment; filename=#{filename}")
|> send_resp(200, content)

The only difference is compress or not:

attr =
  case compress do
    true ->
      :compressed
    false ->
      :utf8
  end
file =
  File.open!(temp_file, [:write, attr])

In both cases, file is corrected created at “temp/”, but I still can’t send compressed file.