Hi

Which one of the following is correct?
1. Delivery of onMessage notifications that accompany order state-changes is best-effort. (i.e. A lost message is lost forever.)
2. Delivery of onMessage notifications that accompany order state-changes is guaranteed eventually if connectivity is not lost permanently. (i.e. A lost message will be retransmitted if delivery is not confirmed.)

In other words: Is it safe to use onMessage for any order management, or does the strategy have to poll the order state?

Isak

Hi,

If you need to monitor the platform connection in your strategy, you can use the CONNECTION_STATUS message. Please take a look at the following JForex Wiki page: https://www.dukascopy.com/wiki/index.php ... connecting.

Hi Support

Sorry, my question was worded complicatedly. What I am asking is this:
For purposes of tracking the state of an order, can onMessage(...) notifications be considered reliable, or does one have to poll order.getState().

This would affect any design fundamentally so surely there must be a definite answer.

Thanks
Isak

Yes, using onMessage notifications is reliable for order state management, if your platform reconnects after disconnection you will receive order change messages.

Thank you Support. There are some in the JForex community who avoid using onMessage for order management, and this is an important consideration in making design decisions, so please bear with me as I ask for confirmation:

Suppose, for example, I have an order, and I want to reliably doSomething() when order is filled. Are the following solutions equally reliable? (Note that my question is about the general concept (of how the message framework is implemented) rather than the actual code provided below.)

 // Solution 1
public void onMessage(IMessage message) throws JFException {
     if(message.getType() == IMessage.Type.ORDER_FILL_OK){
          if(message.getOrder().getID().equals(order.getID())){
               doSomething();
          }
     }
}

 // Solution 2
private IOrder.State lastState;
public void onTick(Instrument instrument, ITick tick){
     if(lastState != IOrder.State.FILLED && order.getState() == IOrder.State.FILLED){
          doSomething();
     }
     lastState = order.getState();
}

Please don't hesitate to say if my question is unclear. Thanks in advance.

About solution 1: In case if fill happens during disconnect, you will not receive ORDER_FILL_OK, and doSomething method will not execute. You need to check ORDER_CHANGED_OK messages as well and see if order changed it's state to the filled.

Solution 2, will work correctly in any case.