The scenario order service creates and manages scenario order handlers which map orders to scenario instances based on the input/output mappings and configuration that the handler defines.
The scenario must be loaded at the time the handler definition is received and its mappings are checked for consistency with the scenario before the handler is created.
Once the handler definition is verified the monitor spawns an mThread for the handler which listens for new orders.
For each new order that the handler receives, a scenario instance is created based on the input mappings and listeners are created for amends, cancels and updates.