db.py 文件源码

def parse_filters(self, filters, doc_class):
        index_name = None
        filter_expression_list = []
        query_params = {}
        for idx, filter in enumerate(filters):
            prop_name, prop_value = filter.split(':')[3:5]
            if idx == 0:
                prop = doc_class()._base_properties[prop_name]
                index_name = prop.kwargs.get(self.index_field_name, None) or \
                             self.default_index_name.format(prop_name)
                query_params['KeyConditionExpression'] = Key(prop_name).eq(prop_value)
            else:
                filter_expression_list.append(Attr(prop_name).eq(prop_value))
        if len(filter_expression_list) > 1:
            query_params['FilterExpression'] = And(*filter_expression_list)
        elif len(filter_expression_list) == 1:
            query_params['FilterExpression'] = filter_expression_list[0]
        if index_name != '_id':
            query_params['IndexName'] = index_name
        return query_params