OrderInitialized

OrderInitialized represents an order having been initialized. The ExecutionEngine applies it to the order, updates the Cache, and publishes it on the MessageBus. It is the seed event that carries enough information to send an order over the wire and reconstruct it identically.

Created locally as the seed event for a new order. Handler: on_order_initialized.

Fields

Beyond the common order event fields, OrderInitialized carries:

Field	Python type	Required/default	Description
`side`	`OrderSide`	Required	The order side (exposed as `event.side`).
`order_type`	`OrderType`	Required	The order type.
`quantity`	`Quantity`	Required	The order quantity.
`time_in_force`	`TimeInForce`	Required	The order time in force.
`post_only`	`bool`	Required	If the order will only provide liquidity (make a market).
`reduce_only`	`bool`	Required	If the order carries the 'reduce‑only' execution instruction.
`quote_quantity`	`bool`	Required	If the order quantity is denominated in the quote currency.
`options`	`dict[str, str]`	Required	Order initialization options for specific order parameters.
`emulation_trigger`	`TriggerType`	`NO_TRIGGER`	The market price trigger for local order emulation.
`trigger_instrument_id`	`InstrumentId` or `None`	Required	The emulation trigger instrument ID (defaults to `instrument_id`).
`contingency_type`	`ContingencyType`	Required	The order contingency type.
`order_list_id`	`OrderListId` or `None`	Required	The order list ID associated with the order.
`linked_order_ids`	`list[ClientOrderId]` or `None`	Required	The linked client order ID(s).
`parent_order_id`	`ClientOrderId` or `None`	Required	The order's parent client order ID.
`exec_algorithm_id`	`ExecAlgorithmId` or `None`	Required	The execution algorithm ID for the order.
`exec_algorithm_params`	`dict[str, Any]` or `None`	Required	The execution algorithm parameters.
`exec_spawn_id`	`ClientOrderId` or `None`	Required	The execution algorithm spawning primary client order ID.
`tags`	`list[str]` or `None`	Required	The custom user tags for the order.

On this event, venue_order_id and account_id are both None, and ts_event equals ts_init. The reconciliation property always returns False here, even for orders reconstructed during reconciliation; later order events such as OrderAccepted carry the real value.

Example

Reading the event in a strategy handler:

def on_order_initialized(self, event: OrderInitialized) -> None:
    self.log.info(
        f"Initialized {event.order_type} {event.side} "
        f"{event.quantity} {event.instrument_id}",
    )

Events - Event categories, dispatch, and the common order event fields.
Orders - Order types and the state machine.

OrderInitialized

Fields

Example

Related guides

On this page