pyignite/connection/protocol_context.py

# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You 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 typing import Tuple

from pyignite.connection.bitmask_feature import BitmaskFeature


class ProtocolContext:
    """
    Protocol context. Provides ability to easily check supported supported
    protocol features.
    """

    def __init__(self, version: Tuple[int, int, int], features: BitmaskFeature = None):
        self._version = version
        self._features = features
        self._ensure_consistency()

    def __hash__(self):
        return hash((self._version, self._features))

    def __eq__(self, other):
        return isinstance(other, ProtocolContext) and \
            self.version == other.version and \
            self.features == other.features

    def __str__(self):
        return f'ProtocolContext(version={self._version}, features={self._features})'

    def _ensure_consistency(self):
        if not self.is_feature_flags_supported():
            self._features = None

    @property
    def version(self):
        return getattr(self, '_version', None)

    @version.setter
    def version(self, version: Tuple[int, int, int]):
        """
        Set version.

        This call may result in features being reset to None if the protocol
        version does not support feature masks.

        :param version: Version to set.
        """
        setattr(self, '_version', version)
        self._ensure_consistency()

    @property
    def features(self):
        return getattr(self, '_features', None)

    @features.setter
    def features(self, features: BitmaskFeature):
        """
        Try and set new feature set.

        If features are not supported by the protocol, None is set as features
        instead.

        :param features: Features to set.
        """
        setattr(self, '_features', features)
        self._ensure_consistency()

    def is_partition_awareness_supported(self) -> bool:
        """
        Check whether partition awareness supported by the current protocol.
        """
        return self.version >= (1, 4, 0)

    def is_status_flags_supported(self) -> bool:
        """
        Check whether status flags supported by the current protocol.
        """
        return self.version >= (1, 4, 0)

    def is_transactions_supported(self) -> bool:
        """
        Check whether transactions supported by the current protocol.
        """
        return self.version >= (1, 6, 0)

    def is_feature_flags_supported(self) -> bool:
        """
        Check whether feature flags supported by the current protocol.
        """
        return self.version >= (1, 7, 0)

    def is_cluster_api_supported(self) -> bool:
        """
        Check whether cluster API supported by the current protocol.
        """
        return self.features and BitmaskFeature.CLUSTER_API in self.features

    def is_expiry_policy_supported(self) -> bool:
        return self.version >= (1, 6, 0)