Rails form_authenticity_token not regenerating after POST request

Question

I was under the impression that Rails will regenerate the form_authenticity_token after any POST, PUT, or DELETE action. But for some reason, after a successful POST to the users resource the form_authenticity_token does not regenerate. I'm free to POST as many time as I would like with the same CSRF token over and over.

I've got a namespaced API and I'm using the RABL gem to build out my responses. This is how I have everything setup...

class Api::V1::UsersController < Api::V1::ApplicationController
  ...
  def create
    @user = User.new(params[:user])
    render "show", :status => (@user.save ? :ok : :unprocessable_entity)
  end
  ...
end

class Api::V1::ApplicationController < ApplicationController
  layout '/api/v1/layouts/application.json.erb'
  respond_to :json
  before_filter :authenticate_user!
  ...
end

class ApplicationController < ActionController::Base
  protect_from_forgery
end

The post goes through fine, there are no errors or warning in the development.log or in the consoled $ rails s log.

I've check verified_request? from within the create method and it's returning true. I've removed the render and setup a create.json.rabl view with the same code as the show.json.rabl view... no dice.

I'm running Rails 3.1.3 w/ Ruby 1.9.2p290 w/ a cookie session store.

The authenticity token is being sent via request header (X-CSRF-Token)

Answer 1

You were under the wrong impressions. As you can see from the relevant bit of the rails source the form authenticity token stays the same for the lifetime of the session.