# Copyright (c) 2013 Mirantis Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
# implied.
# See the License for the specific language governing permissions and
# limitations under the License.

from oslo_serialization import jsonutils
import sqlalchemy as sa


class JsonEncoded(sa.TypeDecorator):
    """Represents an immutable structure as a json-encoded string."""

    impl = sa.Text

    def process_bind_param(self, value, dialect):
        if value is not None:
            value = jsonutils.dumps(value)
        return value

    def process_result_value(self, value, dialect):
        if value is not None:
            value = jsonutils.loads(value)
        return value