Fix tempfile cannot read.

app/controllers/page_contents_controller.rb

@@ -46,6 +46,7 @@ class PageContentsController < OrbitAdminController
             image_file = Tempfile.new
             image_file.binmode
             image_file.write(res.body)
+            image_file.close
             begin
               image = MiniMagick::Image.open(image_file.path)
               IMG_INFO[img_src] = {width: image[:width], height: image[:height]}
@@ -55,7 +56,6 @@ class PageContentsController < OrbitAdminController
               if image[:height]
                 metas << {"property" => "og:image:height", "content" => image[:height].to_s}
               end
-              image_file.close
               image_file.unlink
             rescue MiniMagick::Invalid => e
               puts ["src = #{img_src}", e.to_s]