pyignite/aio_cluster.py

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#      http://www.apache.org/licenses/LICENSE-2.0
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"""
This module contains `AioCluster` that lets you get info and change state of the
whole cluster asynchronously.
"""
from pyignite.api.cluster import cluster_get_state_async, cluster_set_state_async
from pyignite.datatypes import ClusterState
from pyignite.exceptions import ClusterError
from pyignite.utils import status_to_exception


class AioCluster:
    """
    Ignite cluster abstraction. Users should never use this class directly,
    but construct its instances with
    :py:meth:`~pyignite.aio_client.AioClient.get_cluster` method instead.
    """

    def __init__(self, client: 'AioClient'):
        """
        :param client: :py:class:`~pyignite.aio_client.AioClient` instance.
        """
        self._client = client

    @status_to_exception(ClusterError, ignore_timeout=True)
    async def get_state(self) -> 'ClusterState':
        """
        Gets current cluster state.

        :return: Current cluster state. This is one of
         :py:attr:`~pyignite.datatypes.cluster_state.ClusterState.INACTIVE`,
         :py:attr:`~pyignite.datatypes.cluster_state.ClusterState.ACTIVE`,
         :py:attr:`~pyignite.datatypes.cluster_state.ClusterState.ACTIVE_READ_ONLY`.
        """
        return await cluster_get_state_async(await self._client.random_node())

    @status_to_exception(ClusterError, ignore_timeout=True)
    async def set_state(self, state: 'ClusterState'):
        """
        Changes current cluster state to the given.

        Note: Deactivation clears in-memory caches (without persistence)
         including the system caches.

        :param state: New cluster state. This is one of
         :py:attr:`~pyignite.datatypes.cluster_state.ClusterState.INACTIVE`,
         :py:attr:`~pyignite.datatypes.cluster_state.ClusterState.ACTIVE`,
         :py:attr:`~pyignite.datatypes.cluster_state.ClusterState.ACTIVE_READ_ONLY`.
        """
        return await cluster_set_state_async(await self._client.random_node(), state)