private void deriveIndexFields(Field field, Schema schema) {
        IndexField toAdd = new IndexField(field.getName(), Index.convertType(field.getDataType()), field.getDataType());
        com.yahoo.schema.Index definedIndex = schema.getIndex(field.getName());
        if (definedIndex != null) {
            toAdd.setIndexSettings(definedIndex);
        }
        fields.add(toAdd);
        addFieldToCollection(field.getName(), field.getName()); // implicit
    }
Deriver of indexschema config containing information of all text index fields with name and data type.

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