Future()This future object is for subscribe-side calls.
Calling result will resolve the future by returning the message
ID, unless an error occurs.
Methods
Future
Future()Initializes the future. Should not be called by clients.
add_done_callback
add_done_callback(fn)Attaches a callable that will be called when the future finishes.
cancel
cancel()Actions in Pub/Sub generally may not be canceled.
This method always returns False.
cancelled
cancelled()Actions in Pub/Sub generally may not be canceled.
This method always returns False.
done
done()Return True if the future was cancelled or finished executing.
exception
exception(timeout=None)Return the exception raised by the call that the future represents.
| Exceptions | |
|---|---|
| Type | Description |
CancelledError | If the future was cancelled. |
TimeoutError | If the future didn't finish executing before the given timeout. |
result
result(timeout: Optional[Union[int, float]] = None)Return a success code or raise an exception.
This blocks until the operation completes successfully and returns the error code unless an exception is raised.
| Exceptions | |
|---|---|
| Type | Description |
concurrent.futures.TimeoutError | If the request times out. |
AcknowledgeError | If the operation did not succeed for another reason. |
running
running()Return True if the associated Pub/Sub action has not yet completed.
set_exception
set_exception(exception: Optional[BaseException])Set the result of the future as being the given exception.
Do not use this method, it should only be used internally by the library and its unit tests.
set_result
set_result(result: Any)Set the return value of work associated with the future.
Do not use this method, it should only be used internally by the library and its unit tests.
set_running_or_notify_cancel
set_running_or_notify_cancel()Mark the future as running or process any cancel notifications.
Should only be used by Executor implementations and unit tests.
If the future has been cancelled (cancel() was called and returned True) then any threads waiting on the future completing (though calls to as_completed() or wait()) are notified and False is returned.
If the future was not cancelled then it is put in the running state (future calls to running() will return True) and True is returned.
This method should be called by Executor implementations before executing the work associated with this future. If this method returns False then the work should not be executed.
| Exceptions | |
|---|---|
| Type | Description |
RuntimeError | if this method was already called or if set_result() or set_exception() was called. |