add classic google maps onebox

lib/oneboxer/classic_google_maps_onebox.rb

@@ -0,0 +1,26 @@
+require 'net/http'
+require_dependency 'oneboxer/base_onebox'
+
+module Oneboxer
+  class ClassicGoogleMapsOnebox < BaseOnebox
+
+    matcher /^(https?:)?\/\/(maps\.google\.[\w.]{2,}|goo\.gl)\/maps?.+$/
+
+    def onebox
+      @url = get_long_url(@url) if @url.include?("//goo.gl/maps/")
+      "<iframe src='#{@url}&output=embed' width='690px' height='400px' frameborder='0' style='border:0'></iframe>" if @url.present?
+    end
+
+    def get_long_url(url)
+      uri = URI(url)
+      http = Net::HTTP.start(uri.host, uri.port)
+      http.open_timeout = 1
+      http.read_timeout = 1
+      response = http.head(uri.path)
+      response["Location"] if response.code == "301"
+    rescue
+      nil
+    end
+
+  end
+end