Sending a file to the user

Sending a file to the user is easy. Use the send_download/3 function in your Phoenix controller action like this.

# Sending a file from the filesystem
def download(conn, _params) do
  path =
    :my_app
    |> :code.priv_dir()
    |> Path.join("file_in_priv_dir.txt")

  send_download(conn, {:file, path}, filename: "hello.txt")
end

# Sending a file from memory
def download(conn, _params) do
  send_download(conn, {:binary, "hello world"}, filename: "hello.txt")
end

Here I pass the :filename option to set the name under which the file will be saved on the user’s machine.

You can find other options here:
https://hexdocs.pm/phoenix/Phoenix.Controller.html#send_download/3