streaming_pull_manager.py

from abc import ABC, abstractmethod
from typing import Optional, Callable

from google.api_core.exceptions import GoogleAPICallError


CloseCallback = Callable[["StreamingPullManager", Optional[GoogleAPICallError]], None]


class StreamingPullManager(ABC):
  """The API expected by StreamingPullFuture."""
  @abstractmethod
  def add_close_callback(self, close_callback: CloseCallback):
    pass

  @abstractmethod
  def close(self):
    pass