lib/mixpanel/tracker/middleware.rb in mixpanel-1.0.0 vs lib/mixpanel/tracker/middleware.rb in mixpanel-1.1.1

@@ -5,32 +5,35 @@
     class Middleware
       def initialize(app, mixpanel_token, options={})
         @app = app
         @token = mixpanel_token
         @options = {
-          :async => false
+          :async => false,
+          :insert_js_last => false
         }.merge(options)
       end
 
       def call(env)
         @env = env
 
         @status, @headers, @response = @app.call(env)
 
-        update_response!
-        update_content_length!
-        delete_event_queue!
+        if is_trackable_response?
+          update_response!
+          update_content_length!
+          delete_event_queue!
+        end
 
         [@status, @headers, @response]
       end
 
       private
 
       def update_response!
         @response.each do |part|
           if is_regular_request? && is_html_response?
-            insert_at = part.index('</head')
+            insert_at = part.index(@options[:insert_js_last] ? '</body' : '</head')
             unless insert_at.nil?
               part.insert(insert_at, render_event_tracking_scripts) unless queue.empty?
               part.insert(insert_at, render_mixpanel_scripts) #This will insert the mixpanel initialization code before the queue of tracking events.
             end
           elsif is_ajax_request? && is_html_response?
@@ -59,9 +62,13 @@
         @headers["Content-Type"].include?("text/html") if @headers.has_key?("Content-Type")
       end
 
       def is_javascript_response?
         @headers["Content-Type"].include?("text/javascript") if @headers.has_key?("Content-Type")
+      end
+
+      def is_trackable_response?
+        is_html_response? || is_javascript_response?
       end
 
       def render_mixpanel_scripts
         if @options[:async]
             <<-EOT