temporalio/temporal · error

unknown callback state: %v

Error message

unknown callback state: %v

What it means

Error "unknown callback state: %v" thrown in temporalio/temporal.

Source

Thrown at service/history/api/describeworkflow/api.go:421

		return nil, err
	}

	var state enumspb.CallbackState
	switch callback.State() {
	case enumsspb.CALLBACK_STATE_UNSPECIFIED:
		return nil, errCallbackStateUnspecified
	case enumsspb.CALLBACK_STATE_STANDBY:
		state = enumspb.CALLBACK_STATE_STANDBY
	case enumsspb.CALLBACK_STATE_SCHEDULED:
		state = enumspb.CALLBACK_STATE_SCHEDULED
	case enumsspb.CALLBACK_STATE_BACKING_OFF:
		state = enumspb.CALLBACK_STATE_BACKING_OFF
	case enumsspb.CALLBACK_STATE_FAILED:
		state = enumspb.CALLBACK_STATE_FAILED
	case enumsspb.CALLBACK_STATE_SUCCEEDED:
		state = enumspb.CALLBACK_STATE_SUCCEEDED
	default:
		return nil, fmt.Errorf("unknown callback state: %v", callback.State())
	}

	blockedReason := ""
	if state == enumspb.CALLBACK_STATE_SCHEDULED {
		cb := outboundQueueCBPool.Get(tasks.TaskGroupNamespaceIDAndDestination{
			TaskGroup:   callbacks.TaskTypeInvocation,
			NamespaceID: namespaceID.String(),
			Destination: cbSpec.GetNexus().GetUrl(),
		})
		if cb.State() != gobreaker.StateClosed {
			state = enumspb.CALLBACK_STATE_BLOCKED
			blockedReason = "The circuit breaker is open."
		}
	}

	trigger := &workflowpb.CallbackInfo_Trigger{}
	switch callback.Trigger.Variant.(type) {
	case *persistencespb.CallbackInfo_Trigger_WorkflowClosed:

View on GitHub (pinned to bde624efd1)

When it happens

Trigger: Thrown at service/history/api/describeworkflow/api.go:421 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of temporalio/temporal@bde624efd1 (2026-09-01). Data as JSON: /api/errors/bc99b9123844d35a. Report an issue: GitHub.