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How to call the following Remote Server methds

Printed From: IdeaBlade
Category: DevForce
Forum Name: DevForce 2010
Forum Discription: For .NET 4.0
URL: http://www.ideablade.com/forum/forum_posts.asp?TID=2445
Printed Date: 29-Jul-2026 at 1:07pm


Topic: How to call the following Remote Server methds
Posted By: BillG
Subject: How to call the following Remote Server methds
Date Posted: 16-Jan-2011 at 6:13pm
I am having trouble figuring out how to call the following Remote Server Methods.
 
1. public static double GetMemberDuesRate(Member member, DateTime startDate, DateTime endDate) It is located in a folder called RemoteCalls in the LaborWare2011Web project.
 
2. public static void CalculateBalanceOwing(Member member) it is also located in a folder called RemoteCalls in the LaborWare2011Web project.
 
 
Bill
 
 


Replies:
Posted By: sbelini
Date Posted: 18-Jan-2011 at 1:05pm
Hi Bill
 
Like previously stated at
http://www.ideablade.com/forum/forum_posts.asp?TID=2407&KW=&PID=9505&title=what-am-i-missing-in-this-remoteservermethod-call#9505 - http://www.ideablade.com/forum/forum_posts.asp?TID=2407&KW=&PID=9505&title=what-am-i-missing-in-this-remoteservermethod-call#9505
The method called must correspond to the ServerMethodDelegate signature:
 
public delegate object ServerMethodDelegate(
   IPrincipal principal,
   EntityManager serverEntityManager,
   params object[] args
)
 
So your methods' signatures should look like:
 
public static double GetMemberDuesRate(
  IPrincipal principal,
  EntityManager server,
  Member member, DateTime startDate, DateTime endDate
)
 
and
 
public static void CalculateBalanceOwing(
  IPrincipal principal,
  EntityManager server,
  Member member
)
 
Make sure your parameters are serializable.
If for some reason you can't modify your methods to comply with the signature above, I suggest that you create compliant methods and call your methods within them.
 
You can find valuable information about invoking server methods in our http://drc.ideablade.com/xwiki/bin/view/Documentation/InvokeServerMethod - DevForce Resource Center and in the DevForce API documentation as well.
 
Silvio.

Posted By: BillG
Date Posted: 18-Jan-2011 at 7:14pm
Ok  I changed the signature to the following
 

[AllowRpc]

public static void CalculateAmountOwing(IPrincipal principal, EntityManager manager, Member m)

{

so how do I call this method now. Is this correct?

public void CalculateBalance()

{

string typeName = "LaborWare2011Web.RemoteCalls.MemberBalanceCalculator, LaborWare2011Web";

string methodName = "CalculateAmountOwing";

var op = Mgr.InvokeServerMethodAsync(typeName, methodName, Mgr, CurrentMember);

op.Completed += (o, args) => {

};

}

 

Posted By: BillG
Date Posted: 18-Jan-2011 at 7:43pm
Ok so I made the following change according to the documentation
 

public void CalculateBalance()

{

string typeName = "LaborWare2011Web.RemoteCalls.MemberBalanceCalculator, LaborWare2011Web";

string methodName = "CalculateAmountOwing";

var op = Mgr.InvokeServerMethodAsync(typeName, methodName, null, null, CurrentMember);

op.Completed += (o, args) => {

};

}

 

[AllowRpc]

public static void CalculateAmountOwing(IPrincipal principal, EntityManager mgr, params Object[] args)

{

when I step through the code the call to InvokeServerMethodAsync does not call the server method, it just advances past the code.

Posted By: sbelini
Date Posted: 18-Jan-2011 at 8:14pm
Bill,
 
You are invoking the method asynchronously and once it's completed it will invoke the callback (if any).
 
Are you saying that it is not getting to the callback at all?
 
Are you getting any exceptions?
 
Did you try stepping into the server method?

Posted By: BillG
Date Posted: 18-Jan-2011 at 8:25pm
I get an unhandled exceptions code 4004 Category: ManagedRuntimeError
Message:EntityServerException: Could not load type
'LaborWare2011Web.RemoteCalls.MemberBalanceCalculator' from assembly 'LaborWare2011Web.
 

Posted By: BillG
Date Posted: 18-Jan-2011 at 8:34pm
I place  a breakpoint inside of the server method and it never gets called.

Posted By: sbelini
Date Posted: 18-Jan-2011 at 8:44pm
The error means that your assembly-qualified type name is incorrect.
 
As stated in our http://drc.ideablade.com/xwiki/bin/view/Documentation/InvokeServerMethod - DevForce Resource Center , the full type name format is "MyNamespace.MyType, MyAssembly".
 
So yours will most likely be
 
LaborWare2011.RemoteCalls.MemberBalanceCalculator, LaborWare2011Web

Posted By: BillG
Date Posted: 18-Jan-2011 at 8:59pm
Ok now I got further. I get the follwing error message
 
unable to locate public method: MemberBalanceCalculator.CalculateAmountOwing

Posted By: BillG
Date Posted: 18-Jan-2011 at 9:10pm
I think that I know what the problem is now.
 
What do I want for the second parameter for the CalculateAmountOwing method
 
EntityManager mgr
or
LaborWareEntities mgr
 
I tried using the EntityManager mgr and I get an error 'the type initializer for LaborWare2011.RemoteCalls.MemberBalanceCalculator threw an exception. System.TypeInitializationException: The type 'initializer for MemberBalanceCalculator threw an exeption. IdeaBlade.Core.IdeaBladeException: Type conflict: the defaultmanager is currently of type EntityManager.
 
when I use my domain specfic manager it can't find the method because the signature is wrong.
 

Posted By: sbelini
Date Posted: 18-Jan-2011 at 9:42pm
Bill,
 
You'd declare your server method as:
 
[AllowRpc]
public static string CalculateAmountOwing(IPrincipal principal, EntityManager entityManager, params Object[] args){
  Member member = args[0] as Member;
  ...
}
 
and in your application you'd call it as follows:
 
string typeName = "LaborWare2011.RemoteCalls.MemberBalanceCalculator, LaborWare2011Web";
string methodName = "CalculateAmountOwing";
var op = Mgr.InvokeServerMethodAsync(typeName, methodName, null, null, CurrentMember);
 
Are you defining your server method and invoking the method as stated above?
If yes, where exactly is the exception being thrown?
 
Have you checked the documentation about Remote Server Method Calls in our http://drc.ideablade.com/xwiki/bin/view/Documentation/InvokeServerMethod - DevForce Resource Center ?
We'd appreciate some feedback on how we could make this information clearer.
 
Silvio.

Posted By: BillG
Date Posted: 19-Jan-2011 at 8:35am
Two issues I am still having.
 
I thought that the server methods that ran on the server could run synchronous methods. Do the executes and calls in my server methods have to be asychronous? This is what I am trying to do inside of CalculateAmountOwing()
 

1. var query1 = from DuesPaid in _manager.DuesPaids

orderby DuesPaid.BatchDate descending

where DuesPaid.SocSecNo == m.SocSecNo

select DuesPaid;

var results1 = query1.Execute<DuesPaid>();

results1.ForEach(Paid.Add);

2. It will not compile my CalculateAmountOwing if I use the manager object being passed in. example I tried to do the following
 
var query1 = from DuesPaid in manager.DuesPaids and it gave a compile error. Right now in my class I have the following

private static LaborWareEntities _manager = LaborWareEntities.DefaultManager;

 
and I am using _manager to access all properties and it works fine.
 

Posted By: sbelini
Date Posted: 19-Jan-2011 at 9:34am
Bill,
 
1. The Server Method will run synchronously in the server, but the call to the server method is asynchronous because you are using InvokeServerMethodAsync.
i.e.
If you invoke the server method asynchronously (InvokeServerMethodAsync), the code in the client keeps going. Once the Server Method completes, the results are accessible in the callback.
If you invoke the server method synchronously (InvokeServerMethod), the code in the client halts until the Server Method completes. (pretty much like calling a method in the client itself) Then the code in the client continues.
 
Assuming you are not running a Silverlight app, you could invoke the method synchronously by using InvokeServerMethod.
 
2. I'm not sure I understand why it's not compiling. What line of code is causing the error? What is the error message?

Posted By: BillG
Date Posted: 19-Jan-2011 at 10:15am

public static string CalculateAmountOwing(IPrincipal principal, EntityManager manager, params Object[] args)

{

Member m = args[0] as Member;

Paid = new ObservableCollection<DuesPaid>();

Owed = new ObservableCollection<DuesOwed>();

var query1 = from DuesPaid in manager.DuesPaids               doesn't like manager

orderby DuesPaid.BatchDate descending

where DuesPaid.SocSecNo == m.SocSecNo

select DuesPaid;

var results1 = query1.Execute<DuesPaid>();

results1.ForEach(Paid.Add);

Posted By: BillG
Date Posted: 19-Jan-2011 at 10:36am
Is the documentation correct?  Here is your remote server method, it looks like even though you are calling it asychronously your GetQuery is a synchronous call. what is entityManager initialized to?
 
[AllowRpc]
public static int GetNumberOfOrders(IPrincipal principal, EntityManager entityManager,
  params Object[] args) {

 // Gather args
 DateTime startDate = (DateTime) args[0];
  DateTime endDate = (DateTime) args[1];

 return entityManager.GetQuery<OrderSummary>()
    .Where(os => os.OrderDate > startDate && os.OrderDate < endDate)
    .Count();
}
Here is the calling method
 
public void GetOrderCount(DateTime startDate, DateTime endDate) {
 string typeName = "DomainModel.OrderSummary, DomainModel";
 string methodName = "GetNumberOfOrders";

  var op = _em1.InvokeServerMethodAsync(typeName, methodName, null, null, startDate, endDate);  is null, null the principal and the entitymanager
  op.Completed += (o, args) => {
   int myResult = (int)args.Result;
  };
}

Posted By: sbelini
Date Posted: 19-Jan-2011 at 12:14pm
Bill,
 
The example in the documentation is correct.
 
You asked "what is entityManager initialized to"
- For server-side code accepting an EntityManager we create a server-specific EM just for that particular use. In the case of RPC methods it's a bit different in that the type will usually be the type of the calling EM on the client.
 
By the way, in an earlier post, you showed the following line of code:
 
private static LaborWareEntities _manager = LaborWareEntities.DefaultManager;
 
Avoid using static EntityManagers in server-side code. The server code must be able to support multi-threading, and using a static EM means you're opening yourself up to unforeseen multi-threading errors later on. These threading problems usually don't show up in development and early testing, but they show up when you go into production.
 
You mentioned "Here is your remote server method, it looks like even though you are calling it asychronously your GetQuery is a synchronous call"
- Regardless of being called SYNCHRONOUSLY or ASYNCHRONOUSLY in the Client, the Server Method will be executed SYNCHRONOUSLY in the Server.
 
You asked "is null, null the principal and the entitymanager"
- InvokeServerMethodAsync has 3 overloads. The one shown in your post is:
InvokeServerMethodAsync(String,String,Action<InvokeServerMethodOperation>,Object,Object[])
 
Here's a quote from our API documentation:
======================================================================
Asynchronously invokes the specified static (Shared in Visual Basic) method for execution on the server.
Syntax
C#  
public InvokeServerMethodOperation InvokeServerMethodAsync(
   string fullTypeName,
   string methodName,
   Action<InvokeServerMethodOperation> userCallback,
   object userState,
   params object[] userArguments
)
 
Parameters
fullTypeName
Assembly-qualified type name such as 'MyNamespace.Services, MyAssembly'
methodName
Name of method to be invoked
userCallback
Callback called when the operation completes
userState
Token identifying the asynchronous request
userArguments
Arguments to be passed to method
======================================================================
 
You can reference DevForce API Documentation at http://drc.ideablade.com/ApiDocumentation/webframe.html - http://drc.ideablade.com/ApiDocumentation/webframe.html
and also in your machine (installed with DevForce) at Start>Programs>DevForce2010>Documentation>API Documentation.
 
I am also attaching a simple Silverlight App invoking a Server Method based on the example in the http://drc.ideablade.com/xwiki/bin/view/Documentation/InvokeServerMethod - DevForce Resource Center .
You can download the sample http://ideablade.com/friends/SilverlightInvokeServerMethod.zip - here .
 
Silvio.

Posted By: BillG
Date Posted: 19-Jan-2011 at 4:22pm
Thank you so much. I finally have it running. I did get an error about it taking to long to run. Should I use the push feature to get around this?
 
Bill
 


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