Contents

require 'rack/utils'

module GaEvents
  class Middleware
    def initialize(app)
      @app = app
    end
    def call(env)
      # Handle events stored in flash
      # Parts borrowed from Rails:
      # https://github.com/rails/rails/blob/v3.2.14/actionpack/lib/action_dispatch/middleware/flash.rb
      flash = env['rack.session'] && env['rack.session']['flash']
      
      # Fix for Rails 4
      flash &&= flash['flashes'] if Rails::VERSION::MAJOR > 3

      GaEvents::List.init(flash && flash['ga_events'])

      status, headers, response = @app.call(env)

      headers = Rack::Utils::HeaderHash.new(headers)
      if GaEvents::List.present?
        request = Rack::Request.new(env)

        # Can outgrow, headers might get too big
        serialized = GaEvents::List.to_s
        if request.xhr?
          # AJAX request
          headers['X-GA-Events'] = serialized

        elsif (300..399).include?(status)
          # 30x/redirect? Then add event list to flash to survive the redirect.
          flash_hash = env[ActionDispatch::Flash::KEY]
          flash_hash ||= ActionDispatch::Flash::FlashHash.new
          flash_hash['ga_events'] = serialized
          env[ActionDispatch::Flash::KEY] = flash_hash

        elsif is_html?(status, headers)
          body = response
          body = body.each.to_a.join if body.respond_to?(:each)
          body = body.sub('</body>',
            "<div data-ga-events='#{serialized}'></div>\\0")
          response = [body]
        end
      end

      [status, headers, response]
    end

    private

    # Taken from:
    # https://github.com/rack/rack-contrib/blob/master/lib/rack/contrib/jsonp.rb
    def is_html?(status, headers)
      !Rack::Utils::STATUS_WITH_NO_ENTITY_BODY.include?(status.to_i) &&
        headers.key?('Content-Type') &&
        headers['Content-Type'].include?('text/html')
    end
  end
end

Version data entries

2 entries across 2 versions & 1 rubygems

Version	Path
ga_events-1.0.1	lib/ga_events/middleware.rb
ga_events-1.0.0	lib/ga_events/middleware.rb