private static void considerSimpleField(List<ImportedField> importedFields, ImportedField field) {
        ImmutableSDField targetField = field.targetField();
        String targetFieldName = targetField.getName();
        if (!isNestedFieldName(targetFieldName)) {
            if (targetField.doesAttributing()) {
                importedFields.add(field);
            }
        } else {
            Attribute attribute = targetField.getAttribute();
            if (attribute != null) {
                importedFields.add(field);
            }
        }
    }
This class derives imported fields from search definition and produces imported-fields.cfg as needed by the search backend.

@author geirst
config-model/src/main/java/com/yahoo/schema/derived/ImportedFields.java