Environment:
UWP application that uses the .NETCore, "Win 10 for Mobile - 10.0.10240.0"
Scenario:
Tries to consume a netTcpBinding duplex wcf service.
Description:
Have a class derives from the DuplexChannelFactory, When I try to call its ctor(InstanceContext, Binding, EndpointAddress), the PlatformNotSupportedException thrown.
Alternatively, I tried directly "Add Service Reference" from the VS2015 reference, while using that generated client, I got the same result, stack trace is in a snapshot image, so I need to manually type partial of them here:
at System.ServiceModel.ReflectionExtensions.GetInterfaceMap(Type type, Type interfaceType)
at System.ServiceModel.Description.TypeLoader.GetIOperationBehaviorAttributesFromType
....
at System.ServiceModel.ChannelFactory'1.ReflectOnCallbackInstance
at System.ServiceModel.ChannelFactory'1.CreateDescription
at System.ServiceModel.ChannelFactory.InitializeEndpoint
at System.ServiceModel.DuplexChannelFactory'1..ctor
at System.ServiceModel.ClientBase'1..ctor
at System.ServiceModel.DuplexClientBase'1 .. ctor(InstanceContext, Binding, EndpointAddress)
Related
I've been working on implementing the IOrganizationService interface in the CRM 2011 SDK - At first I wrote a simple Windows Service wrapper and this was throwing serialization exceptions any time i tried connecting to it. So I wrote a simple host for IIS. At first it seemed to work but any time there is a Fault in the service it throws the same error when trying to connect to the service after the first attempt.
The formatter threw an exception while trying to deserialize the message: There was an error whi
trying to deserialize parameter http://schemas.microsoft.com/xrm/2011/Contracts/Services:request. The InnerException
message was 'Error in line 1 position 497. Element 'http://schemas.microsoft.com/xrm/2011/Contracts/Services:request
contains data from a type that maps to the name 'http://schemas.microsoft.com/crm/2011/Contracts:WhoAmIRequest'. The
deserializer has no knowledge of any type that maps to this name. Consider changing the implementation of the
ResolveName method on your DataContractResolver to return a non-null value for name 'WhoAmIRequest' and namespace
'http://schemas.microsoft.com/crm/2011/Contracts'.'.
I am at a bit of a loss here - it works fine - throws a fault somwhere - attempt to reconnect and throws this error. After which I must re-compile and deploy the DLL to the IIS site bin dir again. I can provide some small code samples of if needed but keep in mind that I am inheriting the interface directly from the SDK assembly.
EDIT:
And I am unable to change the program the connects to the WCF Service as it is a third-party tool. When using the traditional web-services it is fine.
EDIT (Implementation Code - Excluding the implemented methods ..>):
[AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
[ServiceBehavior(
ConcurrencyMode = ConcurrencyMode.Multiple,
MaxItemsInObjectGraph = int.MaxValue,
Name = "OrganizationServiceImplementation",
Namespace = "http://schemas.microsoft.com/xrm/2011/Contracts")]
public class OrganizationServiceImplementation : IOrganizationService
{
}
I have gone through following references and found that a WCF service can be called dynamically. But, i have not been able to call a service (method) accepting parameters as ref and out.
Calling a WCF service from a client without having the contract interface
Dynamic Programming with WCF
Dynamically Invoking Web Services... With WCF This Time
Invoking WCF Service without adding a Service Reference.
Is there any way to make such call with ref and out parameters?
Invoking WCF Service without adding a Service Reference. works greate provided i know the Contract. So i added the web reference first, copied the generated proxy into actual project and then removed the web refernce and simply called the method as
BasicHttpBinding binding = new BasicHttpBinding();
EndpointAddress epAddr = new EndpointAddress("http://192.168.0.233/GMS/GMSService.svc");
GMSContract.IGMSService _interface = ChannelFactory<GMSContract.IGMSService>.CreateChannel(binding, epAddr);
...
bool r = _interface.MyGMSMethod(..., ref ..., out ..., out ...);
My use-case:
I already have a working ASP.NET application
I would like to implement a new Web Service as part of that application
I am supposed to use a WCF service (*.svc), not an ASP.NET web service (*.asmx)
The service needs to have one operation, let’s call it GetInterface(), which returns instance of an interface. This instance must reside on the server, not be serialized to the client; methods called on that interface must execute on the server.
Here’s what I tried (please tell me where I went wrong):
For the purpose of testing this, I created a new ASP.NET Web Application project called ServiceSide.
Within that project, I added a WCF Service using “Add → New Item”. I called it MainService. This created both a MainService class as well as an IMainService interface.
Now I created a new Class library project called ServiceWorkLibrary to contain only the interface declaration that is to be shared between the client and server, nothing else:
[ServiceContract]
public interface IWorkInterface
{
[OperationContract]
int GetInt();
}
Back in ServiceSide, I replaced the default DoWork() method in the IMainService interface as well as its implementation in the MainService class, and I also added a simple implementation for the shared IWorkInterface. They now look like this:
[ServiceContract]
public interface IMainService
{
[OperationContract]
IWorkInterface GetInterface();
}
public class MainService : IMainService
{
public IWorkInterface GetInterface()
{
return new WorkInterfaceImpl();
}
}
public class WorkInterfaceImpl : MarshalByRefObject, IWorkInterface
{
public int GetInt() { return 47; }
}
Now running this application “works” in the sense that it gives me the default web-service page in the browser which says:
You have created a service.
To test this service, you will need to create a client and use it to
call the service. You can do this using the svcutil.exe tool from the
command line with the following syntax:
svcutil.exe http://localhost:59958/MainService.svc?wsdl
This will generate a configuration file and a code file that contains
the client class. Add the two files to your client application and use
the generated client class to call the Service. For example:
So on to the client then. In a separate Visual Studio, I created a new Console Application project called ClientSide with a new solution. I added the ServiceWorkLibrary project and added the reference to it from ClientSide.
Then I ran the above svcutil.exe call. This generated a MainService.cs and an output.config, which I added to the ClientSide project.
Finally, I added the following code to the Main method:
using (var client = new MainServiceClient())
{
var workInterface = client.GetInterface();
Console.WriteLine(workInterface.GetType().FullName);
}
This already fails with a cryptic exception in the constructor call. I managed to fix this by renaming output.config to App.config.
I notice that the return type of GetInterface() is object instead of IWorkInterface. Anyone know why? But let’s move on...
Now when I run this, I get a CommunicationException when calling GetInterface():
The underlying connection was closed: The connection was closed unexpectedly.
How do I fix this so that I get the IWorkInterface transparent proxy that I expect?
Things I’ve tried
I tried adding [KnownType(typeof(WorkInterfaceImpl))] to the declaration of WorkInterfaceImpl. If I do this, I get a different exception in the same place. It is now a NetDispatcherFaultException with the message:
The formatter threw an exception while trying to deserialize the message: There was an error while trying to deserialize parameter http://tempuri.org/:GetInterfaceResult. The InnerException message was 'Error in line 1 position 491. Element 'http://tempuri.org/:GetInterfaceResult' contains data from a type that maps to the name 'http://schemas.datacontract.org/2004/07/ServiceSide:WorkInterfaceImpl'. The deserializer has no knowledge of any type that maps to this name. Consider using a DataContractResolver or add the type corresponding to 'WorkInterfaceImpl' to the list of known types - for example, by using the KnownTypeAttribute attribute or by adding it to the list of known types passed to DataContractSerializer.'. Please see InnerException for more details.
The InnerException mentioned is a SerializationException with the message:
Error in line 1 position 491. Element 'http://tempuri.org/:GetInterfaceResult' contains data from a type that maps to the name 'http://schemas.datacontract.org/2004/07/ServiceSide:WorkInterfaceImpl'. The deserializer has no knowledge of any type that maps to this name. Consider using a DataContractResolver or add the type corresponding to 'WorkInterfaceImpl' to the list of known types - for example, by using the KnownTypeAttribute attribute or by adding it to the list of known types passed to DataContractSerializer.
Notice how this seems to indicate that the system is trying to serialize the type. It is not supposed to do that. It is supposed to generate a transparent proxy instead. How do I tell it to stop trying to serialize it?
I tried adding an attribute, [ServiceBehavior(InstanceContextMode = InstanceContextMode.PerSession)], to the WorkInterfaceImpl class. No effect.
I tried changing the attribute [ServiceContract] on the IWorkInterface interface (declared in the shared library ServiceWorkLibrary) to [ServiceContract(SessionMode = SessionMode.Required)]. Also no effect.
I also tried adding the following magic system.diagnostics element to the Web.config in ServerSide:
<system.diagnostics>
<!-- This logging is great when WCF does not work. -->
<sources>
<source name="System.ServiceModel" switchValue="Information, ActivityTracing" propagateActivity="true">
<listeners>
<add name="traceListener" type="System.Diagnostics.XmlWriterTraceListener" initializeData="c:\traces.svclog" />
</listeners>
</source>
</sources>
</system.diagnostics>
This does generate the c:\traces.svclog file as promised, but I’m not sure I can make any sense of its contents. I’ve posted the generated file to pastebin here. You can view this information in a more friendly UI by using svctraceviewer.exe. I did that, but frankly, all that stuff doesn’t tell me anything...
What am I doing wrong?
The use-case I am describing is not directly supported by WCF.
The accepted work-around is to return an instance of EndpointAddress10 which points to the service for the “other” interface. The client must then manually create a Channel to access the remote object. WCF doesn’t properly encapsulate this process.
An example that demonstrates this is linked to from the MSDN article “From .NET Remoting to the Windows Communication Foundation (WCF)” (find the text that says “Click here to download the code sample for this article”). This example code demonstrates both .NET Remoting as well as WCF. It defines an interface that looks like this:
[ServiceContract]
public interface IRemoteFactory
{
IMySessionBoundObject GetInstance();
[OperationContract]
EndpointAddress10 GetInstanceAddress();
}
Notice that the interface-returning method is not part of the contract, only the one that returns an EndpointAddress10 is marked with [OperationContract]. The example calls the first method via Remoting, where it correctly creates a remote proxy as one would expect — but when using WCF it resorts to the second method and then instantiates a separate ChannelFactory with the new endpoint address to access the new object.
What is MainServiceClient()? It is the class marshaling the client messages to the server.
You should take a look at a related SO post on returning interfaces as parameters in WCF. ServiceKnownTypeAttribute may be helpful.
Sessions may also be what you're looking for MarshalByRef as it relates to .NET Remoting behaviors.
Another approach (as mentioned on MSDN Forums) is to return the EndpointAddress of the service interface instead of the interface itself.
WCF does serialize everything - regardless of the binding. The best approach you should take if you need to communicate with the service on the same system is to use IPC transport binding (net.pipe).
What you are trying to do is a direct violation of the SOA Tenet: "Services share schema and contract, not class". What this means it that you don't actually pass implementation code from the service to its consumers, just the return values that are specified in the contract itself.
The main focus of WCF and SOA in general is interoperability, meaning services should be accessible to clients of any platform. How would a Java or C++ consumer be able to use this service you are designing? Short answer is that it couldn't, which is why you will find it difficult if not impossible to serialize this code over messaging standards like SOAP.
A more appropriate way to structure this code would be to host each implementation of IWorkerInterface as its own service (it has been defined as a service contract, after all), and expose each service on a different endpoint. Instead of MainService behaving as remote factory for proxies to an IWorkerInterface, it could act a as an endpoint factory to the different services you have set up. Endpoint metadata could easily be serialized and provided to the client by IMainService. The client could then take that metadata and construct a proxy to the remote implementation, either through some custom IServiceProxy implementation, or even through the objects already provided to you by WCF (such as the ChannelFactory).
I am creating a wcf service in .net. In the service I have added function named XYZ as:
public int XYZ(int a){
return a+a;
}
When i added the web reference of web service in my web application and accessed the function XYZ, here it requires two parameters one is of int type and second is of bool type.
But originally i had added single parameter in XYZ function in wcf service.
If someone has idea then please let me know that how to handle this. Because my wcf service will be called from flash code.
If you are adding a Web Reference to your project instead of Service Reference then you'll get "extra" parameters as described here. You should be adding a Service Reference to create a proxy for your service that matches the WCF ServiceContract description of your service. Also, the "extra" parameters only show up for ASMX-based clients. They won't be required for the Flash client to call the WCF Service.
I have a WCF service that I'd like clients to be able to reference using Visual Studio's "Add Service Reference" feature. They've been able to recognize the metadata endpoint, the interfaces, methods and data types appear in the Add Service Reference dialog, and it appears to successfully generate the proxy without a hitch - but when viewing the generated code file or viewing the classes in the object browser, there is no service interface generated from the ServiceContract - only the DataContracts are represented. When I point svcutil at the same endpoint URL from the command line, the generated file does contain the interfaces.
The service itself has been used in production for a while and seems to work fine
It uses a custom binding, but the exact same binding configuration (and other config settings) are used by another service that seems to work fine with Add Service Reference
One thing that is different is that this service uses a custom behavior (an attribute derived from IServiceBehavior). The interface is also in a different assembly from the concrete service type, although so are the data contracts.
Update:
What seems to be causing the problem, which I'd somehow overlooked, is that there are FaultContracts for some of the methods on this interface, and these FaultContracts are referencing an exception type that is [Serializable], not [DataContract] (as I think anything that derives from Exception must be). The exception type itself is represented in the generated code, but its public properties aren't (in either svcutil or ASR-generated code)
What seemed to be causing the problem, which I'd somehow overlooked, is that there are FaultContracts for some of the methods on this interface, and these FaultContracts are referencing an exception type that is [Serializable], not [DataContract] (as I think anything that derives from Exception must be). The exception type itself is represented in the generated code, but its public properties aren't (in either svcutil or ASR-generated code)