Order Placing System
A user places an order and the corresponding amount is kept on hold for the order and an order is created. This order is then pushed to some queue to be used by trade matching system. User gets back a reference order id for the order placed in return to the API call.
Trade Matching System
The system feeds on data from the queue generated by order placing system and looks for possible match and if possible to execute, executes them and push to another queue.
User Notification System
The system fetches data from the executed queue and broadcasts it to the user it belonged to. User can also fetch status of the order from the reference id which was shared on first API call
These two systems are right now communicating indirectly via a queue. Now the requirement is, in order placing system, when a user places order, along with order id, we also need to return execution status (i.e. Whether it got executed or not, if yes, rate and fee charged etc).
What should be mode of communication between order placing and trade matching system to make it possible to return execution details in first api call itself ?
Challenges
- Matching System being single threaded, we cannot merge it with order engine
- Polling and waiting for execution from execution queue, will probably make our order placing API slow
Right now our order placing system and matching system are separate.
Just looking for possible solution and opinion. Please let me know if something is unclear.
