problem invoking devise effectively from a controller

deviseblues

current code https://github.com/markfeedly/social-museum/tree/update-mail

rake routes

  user_session POST     /users/sign_in(.:format)                    devise/sessions#create

devise sessions controller

  # POST /resource/sign_in
  def create
    self.resource = warden.authenticate!(auth_options)
    set_flash_message(:notice, :signed_in) if is_flashing_format?
    sign_in(resource_name, resource)
    yield resource if block_given?
    respond_with resource, :location => after_sign_in_path_for(resource)
  end

mods to ApplicationController

  def store_location
    # store last url - this is needed for post-login redirect to whatever the user last visited.
    return unless request.get?
    if request.path != "/users/sign_in" &&
        request.path != "/users/sign_up" &&
        request.path != "/users/password/new" &&
        request.path != "/users/sign_out" &&
        !request.xhr? # don't store ajax calls
      session[:previous_url] = request.fullpath
      Rails.logger.level = 0
      logger.debug "%%%%%%%%%%%%%%%%%%%%%%%%%%% store_location #{session[:previous_url]} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%"
    end
  end

  def after_sign_in_path_for(resource)
    Rails.logger.level = 0
    logger.debug "%%%%%%%%%%%%%%%%%%%%%%%%%%% after_sign_in_path_for #{session[:previous_url]} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%"

    session[:previous_url] || root_path
  end

rake routes output again

  GET      /pages/:id/unsubscribe-via-email(.:format)  pages#unsubscribe_via_email


Demonstrable incompetence in my PagesController, where obvs I want to ensure someone is logged in

  def unsubscribe_via_email # /pages/:id/unsubscribe-via-email
    if current_user
      render :confirm_unsubcribe
    else
      store_location
      render 'devise/sessions/new'  # <----------- arrugh I don't know what to put here, certainly its not a redirect
    end
  end

where visiting /pages/page_stub_here/unsubscribe-via-email invokes app/views/devise/sessions/new.html.haml but without a resource for this line in the haml

= simple_form_for(resource, :as => resource_name, :url => session_path(resource_name), :html => {:class => 'form-vertical'}) do |f|

where of course I have not supplied resource. I v strongly suspect the clue I need to solve this is in the devise sessions controller, but I wonder if there is a little change I can make to my unsubscribe_via_email action in my page controller

change

def unsubscribe_via_email # /pages/:id/unsubscribe-via-email
  if current_user
    render :confirm_unsubcribe
  else
    store_location
    render 'devise/sessions/new' 
  end
end

to

before_filter :authenticate_user!, only: [:unsubscribe_via_email]

def unsubscribe_via_email # /pages/:id/unsubscribe-via-email
  render :confirm_unsubcribe
end

and, for future reference, yes you did want a redirect ;) that 'store_location' line stores the current location in the session so that devise can redirect back to the same place after you redirect to the devise login page and successfully authenticate.