Results 1 to 3 of 3
  1. #1
    Member
    Join Date
    Jun 2008
    Location
    Glasgow
    Posts
    4

    RAW subscription not pushing all information

    Hi,

    This is a question about the way that the DataAdapter, etc works. I've implemented a DataAdapter and a IExtendedTableListener. In the DataAdapter I create a hashtable to store the update information. Not all of the update information changes every time.

    Would it be fair to say that lightstreamer does not include items in the dictionary that have not changed since the last update? If so, is there any way to force it to always send all data passed to IItemEventListener.Update() regardless of if it has changed or not?

    Cheers,
    Adam

  2. #2
    Member
    Join Date
    Jun 2008
    Location
    Glasgow
    Posts
    4
    I've done a bit more investigation, and found out a bit more about how everything's meant to work. From what I can see, a client can request the mode that they are subscribing to something when creating an ExtendedTableInfo object to pass to SubscribeTable.

    I've tried setting the mode to ExtendedTableInfo.RAW, but this doesn't appear to work properly. I still have missing items being passed to the OnUpdate method (for items that haven't changed).

    I'm not particularly concerned about bandwidth, so I would like to be able to force the server to send the whole update every time.

    Am I correct in my understanding? Thanks for any replies.

    Adam

  3. #3
    Administrator
    Join Date
    Jul 2006
    Location
    Milan
    Posts
    975
    You are correct, but, from our perspective, we say it in a different way.

    The Server-Client communication protocol, in order to save bandwidth, forces unchanged fields not to be sent, but to be replaced by flags that identify unchanged fields.
    We consider this as a not configurable implementation detail, as the client receives enough information to be able to retrieve the unchanged values from previous updates.
    However, some of our client libraries lack support for this task and just forward the "unchanged" notification to application code, rather than resolve unchanged fields under the hood.
    This is what I expect that happens in your case. Note that the "unchanged" notification is expressed differently depending on the kind of listener you are using.

    Fortunately, this limitation is going to be removed with the forthcoming 3.5 release of Lightstreamer (announced in our July 2008 newsletter)
    where a new listener type will be introduced for this purpose, for all client SDKs that are currently affected by the above limitation.

 

 

Similar Threads

  1. on field missing error on javascript execution
    By betasec in forum Client APIs
    Replies: 1
    Last Post: June 8th, 2012, 09:52 AM
  2. Possible missing EOS command?
    By yoadsn in forum General
    Replies: 3
    Last Post: December 22nd, 2011, 01:14 PM
  3. Bad request: LS_Session parameter missing
    By lstest in forum Adapter APIs
    Replies: 5
    Last Post: February 26th, 2010, 03:47 PM
  4. Raw mode subscription, missing snapshot
    By Pradeep Chahal in forum Adapter APIs
    Replies: 1
    Last Post: January 22nd, 2010, 02:57 PM
  5. StocklistConnectionListener missing
    By sukhdev in forum Client APIs
    Replies: 2
    Last Post: July 20th, 2007, 06:44 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
All times are GMT +1. The time now is 03:31 AM.