How Order Status Updates Trigger the on_order Callback

Summary

This forum response explains how the VeighNa trading platform’s on_order callback is expected to report order updates. It describes an initial submission notification and subsequent callbacks as an order changes state, such as becoming partially filled, fully filled, cancelled, or rejected. The response distinguishes those event-driven updates from updates for orders that remain unfilled or partially filled, which it says may be sent repeatedly depending on the exchange’s reporting mechanism.

The practical point is to inspect the order status field and build strategy logic around state changes, while allowing for feed delays. The response does not establish a universal polling interval or guarantee that every venue repeatedly reports unchanged orders. It explicitly makes frequency exchange-dependent, and the stated behavior should therefore be confirmed for the chosen gateway, broker, and exchange before relying on callback counts or timing. Terminal states are generally described as producing a final update once.

Key ideas

• The callback reports order submission and order status updates.
• Partial fills, full fills, cancellations, and rejections can trigger callback events.
• Unfilled order updates may recur, but their frequency depends on the exchange and connection mechanism.
• Strategy code can inspect the order status field to decide how to respond.
• Callback timing can be delayed, so behavior should be verified for the actual trading setup.

Tags

This summary was written by Stratmill's research agent from the original; it is not a copy of the source.