New Posts New Posts RSS Feed: AddAsyncQuery Question
  FAQ FAQ  Forum Search   Calendar   Register Register  Login Login

AddAsyncQuery Question
 Post Reply Post Reply
Author
  Share Topic Share Topic  Topic Search Topic Search  Topic Options Topic Options
skingaby View Drop Down
DevForce MVP
DevForce MVP
Avatar

Joined: 23-Apr-2008
Location: United States
Posts: 146 		Post Options Post Options   Quote skingaby Quote  Post ReplyReply Direct Link To This Post Topic: AddAsyncQuery Question
    Posted: 24-Jul-2009 at 8:01am
I have these methods that initialize my server side Entity Manager cache: 
private static IList<IEntityQuery> GetInitializationQueries()

{

     var queries = new List<IEntityQuery>();

     queries.Add(_defaultManager.AccountingMonths);

     queries.Add(_defaultManager.DealTypes);

     return queries;

}

public static void InitializeCache()

{

     var queries = GetInitializationQueries();

     foreach (var item in queries)

     {

          _defaultManager.ExecuteQuery(item);

     }

}


I am trying to write an AsyncParallelTask to do the same thing for the client, and I can get this to work: 
public static void InitializeCacheAsync(Action<AsyncParallelTaskCompletedArgs> callback)

{

     var task = AsyncParallelTask.Create();

     task.AddExceptionHandler(InitializationExceptionHandler);

     AddInitializationQueries(task);

     task.Execute(callback);

}

private static void AddInitializationQueries(AsyncParallelTask<object> task)

{

     task.AddAsyncQuery(1, x => _defaultManager.AccountingMonths);

     task.AddAsyncQuery(2, x => _defaultManager.DealTypes);

}


I would like to do this instead: 
private static void AddInitializationQueries(AsyncParallelTask<object> task)

{

     var queries = GetInitializationQueries();

     int i = 1;

     foreach (var item in queries)

     {

          task.AddAsyncQuery(i, x => item);

          i++;

     }

}


But the AddAsyncQuery method needs an IEntityQuery<T> but I only have IEntityQuery objects in my collection. Is there any way to work around this? Thanks, Simon
Back to Top
kimj View Drop Down
IdeaBlade
IdeaBlade
Avatar

Joined: 09-May-2007
Posts: 1391 		Post Options Post Options   Quote kimj Quote  Post ReplyReply Direct Link To This Post Posted: 24-Jul-2009 at 10:55am
Yes, there is a workaround.  The extension methods, like AddAsyncQuery, are there to help hide some of the complexities of the syntax, but aren't required.  Here's how you can do this using AddAsyncAction instead:
 


      foreach (var item in queries) {
        task.AddAsyncAction<EntityFetchedEventArgs>(i,
          (args, callback) => _defaultManager.ExecuteQueryAsync(item, callback, null), 
          null);
        i++;
      }
Back to Top
skingaby View Drop Down
DevForce MVP
DevForce MVP
Avatar

Joined: 23-Apr-2008
Location: United States
Posts: 146 		Post Options Post Options   Quote skingaby Quote  Post ReplyReply Direct Link To This Post Posted: 29-Jul-2009 at 7:45am
I'm not getting any errors with this code, but it does not seem to be loading the entities into the cache. My unit tests are getting the Null entity instead. Any suggestions? Thanks, Simon
Back to Top
kimj View Drop Down
IdeaBlade
IdeaBlade
Avatar

Joined: 09-May-2007
Posts: 1391 		Post Options Post Options   Quote kimj Quote  Post ReplyReply Direct Link To This Post Posted: 29-Jul-2009 at 8:33am
Hmm, I'd check the completion action on the AsyncParallelTask to see what it contains, since it will have results from all actions in the task.  I'd also check that the EntityManager used for all queries is the correct one.  Also check to see if an error was caught by your exception handler.  And since it's a test method, make sure it's not exiting prematurely. 
Back to Top
skingaby View Drop Down
DevForce MVP
DevForce MVP
Avatar

Joined: 23-Apr-2008
Location: United States
Posts: 146 		Post Options Post Options   Quote skingaby Quote  Post ReplyReply Direct Link To This Post Posted: 29-Jul-2009 at 1:06pm
Thanks. I've stepped through it now and it does not seem to be erroring anywhere. The completionmap is showing all 6 queries executed and completed with no errors. I have added errorhandlers to the tasks. Nothing seems to be failing, however, when I use this syntax, the cached entities are available: 
public static void InitializeCacheAsync(AsyncCompletedCallback<AsyncEventArgs> serialCallback, Action<AsyncParallelTaskCompletedArgs> completionAction)

{

     var task = AsyncParallelTask.Create();

     task.AddExceptionHandler(InitializationExceptionHandler);

     AddInitializationQueries(task);

     task.Execute(serialCallback, completionAction);

}



private static void AddInitializationQueries(AsyncParallelTask<object> task)

{

     task.AddAsyncQuery(1, x => _defaultManager.AccountingMonths);

     task.AddAsyncQuery(2, x => _defaultManager.DealTypes);

}


When I execute this code, the entities are not available: 
public static void InitializeCacheAsync(AsyncCompletedCallback<AsyncEventArgs> serialCallback, Action<AsyncParallelTaskCompletedArgs> completionAction)

{

     var task = AsyncParallelTask.Create();

     task.AddExceptionHandler(InitializationExceptionHandler);

     AddInitializationQueries(task);

     task.Execute(serialCallback, completionAction);

}



private static void AddInitializationQueries(AsyncParallelTask<object> task)

{

     var queries = GetInitializationQueries();

     int i = 1;

     foreach (var item in queries)

     {

          //task.AddAsyncQuery(i, x => item);

          task.AddAsyncAction<EntityFetchedEventArgs>(i,

               (args, callback) =>

               _defaultManager.ExecuteQueryAsync(item, callback, null),

               null);

          i++;

     }

}

          

private static IList<IEntityQuery> GetInitializationQueries()

{

     var queries = new List<IEntityQuery>();

     queries.Add(_defaultManager.AccountingMonths);

     queries.Add(_defaultManager.DealTypes);

     return queries;

}


Is the problem in making creating the list of queries as an IList<IEntityQuery>? Should it be IList<IUntypedEntityQuery>?
Back to Top
kimj View Drop Down
IdeaBlade
IdeaBlade
Avatar

Joined: 09-May-2007
Posts: 1391 		Post Options Post Options   Quote kimj Quote  Post ReplyReply Direct Link To This Post Posted: 29-Jul-2009 at 4:36pm
Ah, it's a problem with closures within the loop adding the tasks.  Use this instead - 


      foreach (var item in queries) {
        IEntityQuery query = item;
        task.AddAsyncAction<EntityFetchedEventArgs>(i,
          (args, callback) => _defaultManager.ExecuteQueryAsync(query, callback, null),
          null);
        i++;
      }
Back to Top
skingaby View Drop Down
DevForce MVP
DevForce MVP
Avatar

Joined: 23-Apr-2008
Location: United States
Posts: 146 		Post Options Post Options   Quote skingaby Quote  Post ReplyReply Direct Link To This Post Posted: 30-Jul-2009 at 6:45am
That fixed it! Thanks!
Back to Top
 Post Reply Post Reply

Forum Jump Forum Permissions View Drop Down