@upload_data = [ { field_1: "value_1", field_2: "value_2" },
                     { field_3: "value_3", field_4: "value_4" },
                     { field_5: "value_5", field_6: "value_6" } ].map { |h| h.stringify_keys }
    post :create, upload_data: @upload_data, :format => :json