Error: Data structure returned is not convertible in the requested format: Only integer keys supported for array columns on base level. Unsupported string 'metadata' found for row 'array ( 'metrics' => array ( 'nb_visits_0' => array ( 'name' => 'Italy (Visits)', 'logo' => 'plugins/Morpheus/icons/dist/flags/it.png', 'min' => 0.0, 'max' => 419.0, 'change' => '-8%', ), 'nb_visits_1' => array ( 'name' => 'United States (Visits)', 'logo' => 'plugins/Morpheus/icons/dist/flags/us.png', 'min' => 4.0, 'max' => 203.0, 'change' => '+449%', ), 'nb_visits_2' => array ( 'name' => 'U'. Try to call this method with the parameters '&format=original&serialize=1'; you will get the original php data structure serialized.