# --------------------------------------------------------------------------------------------
# Copyright (c) Microsoft Corporation. All rights reserved.
# Licensed under the MIT License. See License.txt in the project root for license information.
# --------------------------------------------------------------------------------------------
from typing import Iterable, Dict, Any, Union, Optional
from abc import abstractmethod
[docs]class CheckpointStore:
"""CheckpointStore deals with the interaction with the chosen storage service.
It can list and claim partition ownerships as well as list and save checkpoints.
"""
[docs] @abstractmethod
def list_ownership(
self,
fully_qualified_namespace: str,
eventhub_name: str,
consumer_group: str,
**kwargs: Any
) -> Iterable[Dict[str, Any]]:
"""Retrieves a complete ownership list from the chosen storage service.
:param str fully_qualified_namespace: The fully qualified namespace that the Event Hub belongs to.
The format is like "<namespace>.servicebus.windows.net".
:param str eventhub_name: The name of the specific Event Hub the partition ownerships are associated with,
relative to the Event Hubs namespace that contains it.
:param str consumer_group: The name of the consumer group the ownerships are associated with.
:rtype: Iterable[Dict[str, Any]], Iterable of dictionaries containing partition ownership information:
- `fully_qualified_namespace` (str): The fully qualified namespace that the Event Hub belongs to.
The format is like "<namespace>.servicebus.windows.net".
- `eventhub_name` (str): The name of the specific Event Hub the checkpoint is associated with,
relative to the Event Hubs namespace that contains it.
- `consumer_group` (str): The name of the consumer group the ownership are associated with.
- `partition_id` (str): The partition ID which the checkpoint is created for.
- `owner_id` (str): A UUID representing the current owner of this partition.
- `last_modified_time` (UTC datetime.datetime): The last time this ownership was claimed.
- `etag` (str): The Etag value for the last time this ownership was modified. Optional depending
on storage implementation.
"""
[docs] @abstractmethod
def claim_ownership(
self,
ownership_list: Iterable[Dict[str, Any]],
**kwargs: Any
) -> Iterable[Dict[str, Any]]:
"""Tries to claim ownership for a list of specified partitions.
:param Iterable[Dict[str,Any]] ownership_list: Iterable of dictionaries containing all the ownerships to claim.
:rtype: Iterable[Dict[str,Any]], Iterable of dictionaries containing partition ownership information:
- `fully_qualified_namespace` (str): The fully qualified namespace that the Event Hub belongs to.
The format is like "<namespace>.servicebus.windows.net".
- `eventhub_name` (str): The name of the specific Event Hub the checkpoint is associated with,
relative to the Event Hubs namespace that contains it.
- `consumer_group` (str): The name of the consumer group the ownership are associated with.
- `partition_id` (str): The partition ID which the checkpoint is created for.
- `owner_id` (str): A UUID representing the owner attempting to claim this partition.
- `last_modified_time` (UTC datetime.datetime): The last time this ownership was claimed.
- `etag` (str): The Etag value for the last time this ownership was modified. Optional depending
on storage implementation.
"""
[docs] @abstractmethod
def update_checkpoint(self, checkpoint: Dict[str, Optional[Union[str, int]]], **kwargs: Any) -> None:
"""Updates the checkpoint using the given information for the offset, associated partition and
consumer group in the chosen storage service.
Note: If you plan to implement a custom checkpoint store with the intention of running between
cross-language EventHubs SDKs, it is recommended to persist the offset value as an integer.
:param Dict[str,Any] checkpoint: A dict containing checkpoint information:
- `fully_qualified_namespace` (str): The fully qualified namespace that the Event Hub belongs to.
The format is like "<namespace>.servicebus.windows.net".
- `eventhub_name` (str): The name of the specific Event Hub the checkpoint is associated with,
relative to the Event Hubs namespace that contains it.
- `consumer_group` (str): The name of the consumer group the checkpoint is associated with.
- `partition_id` (str): The partition ID which the checkpoint is created for.
- `sequence_number` (int): The sequence number of the :class:`EventData<azure.eventhub.EventData>`
the new checkpoint will be associated with.
- `offset` (str): The offset of the :class:`EventData<azure.eventhub.EventData>`
the new checkpoint will be associated with.
:rtype: None
"""
[docs] @abstractmethod
def list_checkpoints(
self,
fully_qualified_namespace: str,
eventhub_name: str,
consumer_group: str,
**kwargs: Any
) -> Iterable[Dict[str, Any]]:
"""List the updated checkpoints from the chosen storage service.
:param str fully_qualified_namespace: The fully qualified namespace that the Event Hub belongs to.
The format is like "<namespace>.servicebus.windows.net".
:param str eventhub_name: The name of the specific Event Hub the checkpoints are associated with, relative to
the Event Hubs namespace that contains it.
:param str consumer_group: The name of the consumer group the checkpoints are associated with.
:rtype: Iterable[Dict[str,Any]], Iterable of dictionaries containing partition checkpoint information:
- `fully_qualified_namespace` (str): The fully qualified namespace that the Event Hub belongs to.
The format is like "<namespace>.servicebus.windows.net".
- `eventhub_name` (str): The name of the specific Event Hub the checkpoints are associated with,
relative to the Event Hubs namespace that contains it.
- `consumer_group` (str): The name of the consumer group the checkpoints are associated with.
- `partition_id` (str): The partition ID which the checkpoint is created for.
- `sequence_number` (int): The sequence number of the :class:`EventData<azure.eventhub.EventData>`.
- `offset` (str): The offset of the :class:`EventData<azure.eventhub.EventData>`.
"""