Docs for using session cookie from GA

[tpitale]

How to use cookie from GA on the rails backend.

[jtomaszewski]

Currently setting it up in my app. Some info lies here https://github.com/tpitale/staccato/issues/38 .

[jtomaszewski]

I added such method to my ApplicationController:

  def staccato_client_id
    session["staccato.client_id"] ||= cookies["_ga"].split(".").last(2).join(".") if cookies["_ga"]
    session["staccato.client_id"] ||= Staccato.build_client_id
  end

This will parse the client_id which is set automatically by GA JS library (see this comment for more info). I will test it tomorrow.

If it works correctly, should we merge it in the master?

[tpitale]

Based on this comment, I would probably not want this in code, but we could definitely add it to the README.