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How can I specify a namespace for OperationContract when using WCF?

I am creating a client for a server api I can't change. My client currently produces this format:
<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/">
<s:Body>
<StoreSomething xmlns="urn:aaa">
<Something>
<SomeText xmlns="urn:bbb">My text</SomeText>
</Something>
</StoreSomething>
</s:Body>
</s:Envelope>
However, the server expects Something to be in the urn:bbb namespace (i.e. move the xmlns attribute one level up). How can I achieve this?
OperationContractAttribute has no Namespace property.
Code:
using System;
using System.ServiceModel;
using System.Xml.Serialization;
[XmlType(Namespace="urn:bbb")]
public class Something
{
public string SomeText { get; set; }
}
[XmlSerializerFormat]
[ServiceContract(Namespace="urn:aaa")]
public interface IMyService
{
[OperationContract]
void StoreSomething(Something Something);
}
class Program
{
static void Main(string[] args)
{
var uri = new Uri("http://localhost/WebService/services/Store");
var factory = new ChannelFactory<IMyService>(new BasicHttpBinding(), new EndpointAddress(uri));
IMyService service = factory.CreateChannel();
service.StoreSomething(new Something
{
SomeText = "My text"
});
}
}

I managed to get it working by using unwrapped messages. This unfortunately results in both the method name and parameter name being left out. I therefore had to create wrapper classes which results in convoluted code.
Anyway, here is the code that made it work:
[ServiceContract]
public interface IMyService
{
[OperationContract]
[XmlSerializerFormat]
void StoreSomething(StoreSomethingMessage message);
}
[MessageContract(IsWrapped=false)]
public class StoreSomethingMessage
{
[MessageBodyMember(Namespace="urn:aaa")]
public StoreSomething StoreSomething { get; set; }
}
[XmlType(Namespace="urn:bbb")]
public class StoreSomething
{
public Something Something { get; set; }
}
public class Something
{
public string SomeText { get; set; }
}
I also created a MyServiceClient which implements IMyService and inherits from ClientBase<IMyService> since IMyService now requires a StoreSomethingMessage object, but i left that part out for simplicity.
I wish there was a simpler solution.

Using the same dll in a web service and a client application

I'm updating a few web services that have some components in common, so I thought that by creating a library that has that code in it, it could ease maintenance. When using a class from said library, the web service forces me to call the method with its proxy class.
Since the system is somewhat old, I can't change the architecture. The compilation is made in x64. I've already attempted to change the "Reuse types in referenced assemblies".
Referencing a class "x" from the "y" library on a web service "w" forces me to use the class "w.x" instead of "y.x" on a service method call.
Best regards,
Fábio Jesus
The code that I can provide is the following:
Library
namespace Library1
{
public class Class1
{
}
}
Service
namespace Services
{
[ServiceContract]
public interface Service
{
[OperationContract]
void Method(Library1.Class1 cc);
}
}
Client
namespace Client
{
public class ClientControl : PageControl
{
public void Execute(){
using(var _service = new Services.Service){
var cc = new Library1.Class1();
_service.Method(cc);
}
}
}
}

Cannot create an instance of the abstract class or interface on WCF Silverlight Service

I'm working through two tutorials to create a super simple WCF web service and Silverlight app.
Buiding a Service
Accessing a Service from Silverlight
Everything was going fine. I created my service:
using System;
using System.Linq;
using System.Runtime.Serialization;
using System.ServiceModel;
using System.ServiceModel.Activation;
namespace TestOnline.Web.Data
{
[ServiceContract(Namespace = "")]
[SilverlightFaultBehavior]
[AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
public class DataService
{
[OperationContract]
public String TestService()
{
return "Service Worked!";
}
}
}
I added it as a service reference, then tried to create an instance but I'm getting the error "Cannot create an instance of the abstract class or interface" on the line "proxy = new DataService();"
I pretty much followed the steps of the tutorial exactly, I'm unsure what I've missed. I've certainly not seen many Service examples with constructors, and the reference code is auto-generated - so I don't want to go adding them manually to that.
Does anyone know of a solution/what I've done wrong? Thanks
using System.ServiceModel;
using TestOnline.ServiceReference1;
namespace TestOnline
{
public partial class MainPage : UserControl
{
DataService proxy;
public MainPage()
{
InitializeComponent();
proxy = new DataService();
}
private void TestServiceButton_Click(object sender, RoutedEventArgs e)
{
//call service and get response
}
}
}

You should be creating an instance of the generated proxy client class.
It'll be named DataServiceClient() if it's been added correctly.

Getting a Windows Service to send active values back to WCF client

I have a Windows service that uses net.pipe as a WCF server and a Windows forms client to connect to it. There is a class called ConfigSettings that has values I want the client to query.
I want to have the client read the current values inside the serviceConfig instance that the service uses. Ultimately, I want the client to change values in it, but baby steps first.
The form can talk to the server via named pipes, but 'return serviceConfig is sending a new empty instance back to the client. I want the data that the service is actively using (that is, serviceConfig.Setting1 = x; serviceConfig.Setting2 = "foo"; )
The Windows service and WCF server code is (updated to working version):
using System.IO;
using System.ServiceModel;
using System.ServiceProcess;
namespace WindowsServiceTest
{
public partial class Service1 : ServiceBase
{
internal static ServiceHost myServiceHost = null;
//this is the master config that the service uses
public static ConfigSettings serviceConfig = new ConfigSettings();
public Service1()
{
InitializeComponent();
}
protected override void OnStart(string[] args)
{
if (myServiceHost != null)
{
myServiceHost.Close();
}
myServiceHost = new ServiceHost(typeof(WCFService1));
myServiceHost.Open();
//set active default settings
serviceConfig.Setting1 = 1;
serviceConfig.Setting2 = "initial.Setting2:" + serviceConfig.Setting1;
}
protected override void OnStop()
{
if (myServiceHost != null)
{
myServiceHost.Close();
myServiceHost = null;
}
}
}
public partial class WCFService1 : IService1
{
public ConfigSettings GetConfig()
{
return Service1.serviceConfig;
}
public void SetConfig(ConfigSettings sentConfig)
{
Service1.serviceConfig = sentConfig;
}
}
[ServiceContract]
public interface IService1
{
[OperationContract]
ConfigSettings GetConfig();
[OperationContract]
void SetConfig(ConfigSettings sentConfig);
}
public class ConfigSettings
{
public int Setting1 { get; set; }
public string Setting2 { get; set; }
public ConfigSettings() { }
}
}
The client retrieves the config like this (updated with some changes):
using System;
using System.ServiceProcess;
using System.Windows.Forms;
using WindowsServiceTest;
namespace WindowsServiceTestForm
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
ConfigSettings config = new ConfigSettings();
//GetConfig()
private void button1_Click(object sender, EventArgs e)
{
ServiceReference1.Service1Client myService = new ServiceReference1.Service1Client();
ServiceControllerPermission scp = new ServiceControllerPermission(ServiceControllerPermissionAccess.Control, Environment.MachineName, "Service1");//this will grant permission to access the Service
//get the current config and display
config = myService.GetConfig();
MessageBox.Show(config.Setting1 + "\r\n" + config.Setting2, "config");
myService.Close();
}
//SetConfig(ConfigSettings)
private void button2_Click(object sender, EventArgs e)
{ //make changes to values
config.Setting1 += 1;
config.Setting2 = "new.Setting2:" + config.Setting1;
ServiceReference1.Service1Client myService = new ServiceReference1.Service1Client();
ServiceControllerPermission scp = new ServiceControllerPermission(ServiceControllerPermissionAccess.Control, Environment.MachineName, "Service1");//this will grant permission to access the Service
//send the new config
myService.SetConfig(config);
myService.Close();
}
}
}
Update:
Maybe what I'm thinking needs to be done is overkill. It seems that I'm hitting a membrane between WCF and the Windows Service.
How would YOU approach this problem?
Windows Service that needs a Form for configuration.
When service starts, it loads a config.xml file from disk. (a serialized class)
When GUI starts, I want to:
retrieve its current configuration,
make some changes to it,
push it back to the service,
trigger service to re-read and react to the new configuration.
I was trying to avoid statically/writing the config file to disk and telling service to re-read it again. It "seemed" like WCF was the way to go.
Update 2
It seems that by just changing the master config in the service to static, the WCF service can access it directly. I could have sworn I did that originally before I posted, but I guess not.
I also separated the naming of Service1 to WCFService1 above, but it turns out that doesn't matter and works either way.
New complete code has been updated above.

You are getting confused between Windows Service and WCF Service - and have tried to have them both in the same class - while this is possible - it is probably easier to understand if you split them into two classes.
In your example the Windows Service starts, creates a new instance of itself as the WCF service then sets the config elements in the Windows Service instance, meaning the config is empty in the WCF Service instance.
try this instead
using System.ServiceModel;
using System.ServiceProcess;
namespace WindowsServiceTest
{
public partial class Service1 : ServiceBase
{
internal static ServiceHost myServiceHost = null;
public Service1()
{
InitializeComponent();
}
protected override void OnStart(string[] args)
{
if (myServiceHost != null)
{
myServiceHost.Close();
}
myServiceHost = new ServiceHost(typeof(WCFService1 ));
myServiceHost.Open();
}
protected override void OnStop()
{
if (myServiceHost != null)
{
myServiceHost.Close();
myServiceHost = null;
}
}
}
public class WCFService1 : IService1
{
public WCFService1()
{
//change master settings from null
myConfig.Setting1 = "123";
myConfig.Setting2 = "456";
}
//this is the master config that the service uses
public ConfigSettings myConfig = new ConfigSettings();
public ConfigSettings GetConfig()
{
return myConfig;
}
}
[ServiceContract]
public interface IService1
{
[OperationContract]
ConfigSettings GetConfig();
}
public class ConfigSettings
{
public string Setting1 { get; set; }
public string Setting2 { get; set; }
public ConfigSettings()
{ }
}
}

There are a few ways of doing this (injecting dependencies in the service instance). I'll show two of them.
You have a special case here because the Windows Service is also your WCF service implementation. I think that soon enough you will want to separate them. So, my samples are based on a separate WCF service implementation.
The thing is that WCF has a concept of service instance mode. By default it is PerCall, meaning that a new Service1 instance is created to handle each request. This makes it a bit more difficult to inject something in these instances.
The simplest way is to set the instance mode to Single, meaning there will be only one Service1 instance handling all requests.
The second is easy to implement:
[ServiceBehavior(InstanceContextMode = InstanceContextMode.Single)]
public class Service1Implementation : IService1
{
private ConfigSettings _configSettings;
public Service1(ConfigSettings settings)
{
//now you have the settings in the service
_configSettings = setting;
}
...
}
//in the Windows Service
myServiceHost = new ServiceHost(typeof(Service1Implementation), new Service1Implementation(myConfig));
myServiceHost.Open();
The first solution involves you creating and specifying a service instance factory which the infrastructure will use later to create service instances per call.
The factory gives you the possibility to instantiate Service1 yourself and pass the config.
There is quite some code to be written for this, but I'll show the essential. For the complete solution, read this.
For you, it's easier to make the Windows Service just implement IInstanceProvider:
public class Service1 : ServiceBase, IInstanceProvider
{
private ConfigSettings _myConfig; //assign this member later on
...
//IInstanceProvider implementation
public object GetInstance(InstanceContext instanceContext, Message message)
{
//this is how you inject the config
return new Service1Implementation(_myConfig);
}
public object GetInstance(InstanceContext instanceContext)
{
return this.GetInstance(instanceContext, null);
}
public void ReleaseInstance(InstanceContext instanceContext, object instance)
{
}
...
}

I will admit that it's been a while since I've touched WCF, but it looks to me like your ConfigSettings class is missing some attributes required to make it serializable via WCF.
using System.Runtime.Serialization;
[DataContract]
public class ConfigSettings
{
[DataMember]
public string Setting1 { get; set; }
[DataMember]
public string Setting2 { get; set; }
public ConfigSettings()
{ }
}
I don't believe having your Windows service operate as your WCF service, like other answers have suggested, is the problem. But I do agree that it's best to have them be separate classes.

wcf callback reference

I have a desktop app with a duplex WCF service, but I have some troubles using the callback.
The service is started as following in main of program.cs:
ServiceHost svcHost = new ServiceHost(typeof(PeriodicService));
svcHost.Open();
Console.WriteLine("Available Endpoints :\n");
svcHost.Description.Endpoints.ToList().ForEach(endpoint => Console.WriteLine(endpoint.Address.ToString() + " -- " + endpoint.Name));
For the service I created a subscribe function where the callbackchannel is saved in a global variable, then the callback uses that global variable to talk back to the client (there will be only one client connecting).
IPeriodicCallback callbackClient;
public IPeriodicCallback Proxy
{
get
{
return this.callbackClient;
}
}
public void joinPeriodicService()
{
Console.WriteLine("Client subscribe");
this.callbackClient = OperationContext.Current.GetCallbackChannel<IPeriodicCallback>();
}
The thing I want to do now is call the callbackclient from an other class.
In the other class I created the service as:
private PeriodicService periodicService = new PeriodicService();
And I try to write data to it using:
if(this.periodicService.Proxy != null)
{
this.periodicService.Proxy.On1MinuteDataAvailable(tmpPeriod);
}
However the proxy stays null, I also tried to move the proxy part to the class but this also results in it staying null.
When the client connects I nicely get the message "Client Subscribe" but it seems there are two instances running of the periodicservice.
But my problem is I don't see an other way to access the periodicservice then creating it in my class, or is it also already created by the svcHost?
Can ayone point me in the right direction?

This repository shows the a duplex WCF imeplementation I made to answer a similar question a while ago, its a full working example with as little extra stuff as possible.
https://github.com/Aelphaeis/MyWcfDuplexPipeExample
Lets say we have a Service Contract like this :
[ServiceContract(CallbackContract = typeof(IMyServiceCallback),SessionMode = SessionMode.Required)]
public interface IMyService
{
[OperationContract(IsOneWay=true)]
void DoWork();
}
Note that I specified a CallbackContract.
If you want to make a duplex, you would want to perhaps make your Service Behavior implementation of the above contract like this :
[ServiceBehavior(InstanceContextMode = InstanceContextMode.PerSession)]
public class MyService : IMyService
{
public void DoWork()
{
Console.WriteLine("Hello World");
Callback.WorkComplete();
}
IMyServiceCallback Callback
{
get
{
return OperationContext.Current.GetCallbackChannel<IMyServiceCallback>();
}
}
}
The important thing here is the Callback. This is how your service would allow you to access specified to you by the Client.
You also need to define the callback interface, In my case its quite simple :
[ServiceContract]
public interface IMyServiceCallback
{
[OperationContract(IsOneWay = true)]
void WorkComplete();
}
Now I want to create a client to use this Duplex Service. The first thing I need to do is implement the IMyServiceCallback. I need to do this on the client. In this case the implementation is this:
class Callback : IMyServiceCallback
{
public void WorkComplete()
{
Console.WriteLine("Work Complete");
}
}
Now when I want to open my duplex connection with the services I would create a proxy class like this something like this:
public class MyServiceClient: IMyService, IDisposable
{
DuplexChannelFactory<IMyService> myServiceFactory { get; set; }
public MyServiceClient(IMyServiceCallback Callback)
{
InstanceContext site = new InstanceContext(Callback);
NetNamedPipeBinding binding = new NetNamedPipeBinding();
EndpointAddress endpointAddress = new EndpointAddress(Constants.myPipeService + #"/" + Constants.myPipeServiceName);
myServiceFactory = new DuplexChannelFactory<IMyService>(site, binding, endpointAddress);
}
public void DoWork()
{
myServiceFactory.CreateChannel().DoWork();
}
public void Dispose()
{
myServiceFactory.Close();
}
}
Notice that I specified an InstanceContext. That Instance Context will be an instance of the object I created that implements IMyServiceCallback.
That's all you need to do! Simple as that!
Update :
Callback objects are just like any other object. You can store them into a collection and iterate through them and based on some condition.
One way is to create a property in the IMyServiceCallback that can uniquely identify it. When a client connects to the service it can call a method which specifies a callback object which can then be cached or saved for later use. You can then iterate the callbacks and based on some condition you can call a method for a specific client.
This is certainly more complicated; however, it is certainly manageable. I will add an example in a bit.
Update 2
This is a working example of exactly what you want; however, its a lot more complicated. I'll try to explain as simply as I can : https://github.com/Aelphaeis/MyWcfDuplexPipeExample/tree/MultiClient
Here is a list of the changes:
I've modified the client proxy (and service) so that when initialized it calls the init Method
I've also modified the Service implementation so that now it is a single instance dealing with all requests (for convenience).
I added a new OperationContract in the Service interface called Msg
I've added a new Method in the IMyServiceCallback called RecieveMessage.
I've added a way to identify the client.
In the proxy class I have the following :
public MyServiceClient(IMyServiceCallback Callback)
{
InstanceContext site = new InstanceContext(Callback);
NetNamedPipeBinding binding = new NetNamedPipeBinding();
EndpointAddress endpointAddress = new EndpointAddress(Constants.myPipeService + #"/" + Constants.myPipeServiceName);
myServiceFactory = new DuplexChannelFactory<IMyService>(site, binding, endpointAddress);
Init();
}
public void Init()
{
myServiceFactory.CreateChannel().Init();
}
In my service I have the following :
public class MyService : IMyService
{
public List<IMyServiceCallback> Callbacks { get; private set; }
public MyService(){
Callbacks = new List<IMyServiceCallback>();
}
public void Init()
{
Callbacks.Add(Callback);
}
// and so on
My IMyServiceCallback has been redefined to :
[ServiceContract]
public interface IMyServiceCallback
{
[OperationContract]
int GetClientId();
[OperationContract(IsOneWay = true)]
void WorkComplete();
[OperationContract(IsOneWay = true)]
void RecieveMessage(String msg);
}
By specifying a number, you can contact the client that corresponds with that number. If two clients have the same Id, both clients will be contacted.