application_router.ex

# I want to create an action that returns a chunked response, waiting 1 second between chunks.
# Honestly, I don't understand a single word of the documentation.
# Thats my code

defmodule ApplicationRouter do
  use Dynamo.Router

  prepare do
    # Pick which parts of the request you want to fetch
    # You can comment the line below if you don't need
    # any of them or move them to a forwarded router
    conn.fetch([:cookies, :params])
  end

  defp on_wake_up(msg, conn) do
    conn.assigns[:parent] <- :awaken
    conn.chunk "Hello\n"
  end

  defp await_wake_up(pid) do
    pid <- "hello"

    receive do
      :awaken -> true
    after
      1000 -> await_wake_up(pid)
    end
  end

  get "/story1/play" do
    conn = conn.assign(:parent, self())
    conn = conn.send_chunked(200)

    pid = spawn_link fn ->
      hibernate conn, fn(msg, conn) ->
        { :ok, conn } = on_wake_up(msg, conn)
      end
    end

    await_wake_up(pid)
    conn
  end
end


# When I send a curl request I get the output in the curl_output.txt file
# My final goal is to create an action that reads a .txt file containing an story
# and chunks each line of the text file with a second between them.
# As you see in the output, I don't know how to create a loop, I only get one
# chunk. I'm absolutely lost.

curl_output.txt

$ curl -i http://localhost:4000/story1/play
HTTP/1.1 200 OK
transfer-encoding: chunked
connection: keep-alive
server: Cowboy
date: Sun, 28 Apr 2013 19:40:39 GMT
cache-control: max-age=0, private, must-revalidate

Hello