fixes #693

app/models/upload.rb

@@ -12,11 +12,24 @@ class Upload < ActiveRecord::Base
   before_create :convert_cgi_file
   after_destroy :delete_temp_file
   validate :uploader_is_not_limited
+  validate :file_or_source_is_present
     
   module ValidationMethods
     def uploader_is_not_limited
       if !uploader.can_upload?
-        raise Error.new(uploader.upload_limited_reason)
+        self.errors.add(:uploader, uploader.upload_limited_reason)
+        return false
+      else
+        return true
+      end
+    end
+
+    def file_or_source_is_present
+      if file.blank? && source.blank?
+        self.errors.add(:base, "Must choose file or specify source")
+        return false
+      else
+        return true
       end
     end