Represents something which can check the current state of the exchange queues.
This is current kept separate from the Exchange signature so as
(1) to require/expose less about a particular exchange itself
(2) more practically, expose potentially separate APIs in cases such as e.g. our ui
Represents something which can check the current state of the exchange queues.
This is current kept separate from the Exchange signature so as (1) to require/expose less about a particular exchange itself (2) more practically, expose potentially separate APIs in cases such as e.g. our ui