Authority rules
These are the authority rules for com.apama.oms:
Only publishers should send new orders
Only a publisher actor should send NewOrder events.
Only the publisher that sent a new order event can amend or cancel that order
To simplify the implementation of order publishers, only the publisher that sent a particular NewOrder event can send AmendOrder or CancelOrder events with a matching order identifier. The publisher that creates an order owns the order.
Only receivers update orders
Order receivers publish the current state of an order. Publishers ask to make changes using new, amend and cancel order events.
Only one receiver can send updates for any particular order
Only one order receiver can give the definitive status of an order. This means only one order receiver can send updates for it. The usual way to ensure this is to use the service identifier to determine which receiver should be used. Other actors must not send order updates for an order owned by another receiver.
Order monitors send no events
Order monitors listen, but they do not pass any of the events involved in the protocol. While they are not described further in the rest of this document, they must follow the rules described for publishers and receivers, in order to correctly interpret the state of the order.