Could you please confirm if level 2 fields would be included in refresh message when client first connected to ADS? Client is using C++ API via EMA.
If yes could you please provide a few samples for the following RIC that I can show client how to extract level 2 data from refresh? After subscribing, are we providing accumulated update for the RICs or do we provide full book in every update message? Thank you.
When you connect and login to an ADS - you are doing just that establish a connection and then logging in with your credentials.
Once successfully logged in - an application can request Level and Level 2 real-time streaming data as and when required.
When they request a valid permissioned instrument, they should receive a Refresh message which contains all the fields for that instrument - even ones that are blank at the time of the response.
After this time, they will receive Updates as and when to reflect market activity.
In terms of Level 2 data - are you talking about full depth order books or just Top of order book (e.g. top 5 or 10 orders)?
For full-depth order book, you will receive every single open order in the Refresh response. IF the order book is quite deep, then the order book is spread across multiple Refresh message - the final message with a Completion flag set to true (or false Flag ommited)..
Update Messages will only contain changes to the order book e.g. Add new Order, Change existing order, Delete order.
I was unable to capture the mentioned example RICs above as the Order book is empty right now. So, I captured an LSE RIC and include the output.
Note how up to line 28 to 4043 is the Refresh Message response, after which you receive Updates. Note also how all but the last Refresh has a "Complete":false..
Please see the following article for more details:
and also this one may be useful for deeper understanding:
As mentioned in my earlier response 'line 28 to 4043 is the Refresh Message response, after which you receive Updates. Note also how all but the last Refresh has a "Complete":false.. '
Please refer to the final Refresh message from line 3006 to line 4043. As you will note, the Complete flag has been omitted from this Refresh msg - but is present in the previous two Refresh Msgs.