I have a schema file that describes a choice between multiple layout formats for a type. How do I build a proxy that matches this schema? The reason that this is probably not working is because DataContractSerializer for the most part does not support ambiguous, optional, or multiply-described sections of types. Using svcutil and specifying the serializer to be XmlSerializer is more likely to generate the expected proxy type. Here's a rough guide to what DataContractSerializer does not support for

How do I specify that the client proxy should not have a setter for a particular data member? It doesn't make sense for the service to be able to dictate what the client can do with a piece of data. Once data has been put on the wire, you can't stop the other side that is receiving the message from doing whatever they want with that data. Schema and metadata don't have any notion of access modifiers, but let's say that they did. You might say in the metadata that a certain piece of data has restricted

When I create a channel to a service, how do I know when the service is ready to process the data for that channel? A channel doesn't really know what the service is doing. The service might be actively processing the data being sent over the channel. Or, the service might not. There is a constant tension in the system between components that want to push data and components that want to pull data. Components that push data actively work as long as there is data available until a back pressure builds

How can I find the pipe object on the system created by a named pipe binding? The simplest way to find the named pipe is to use a tool like Process Explorer to examine your running executable. If you look inside a client or service that has the named pipe open, then you'll see a file handle that looks like this: \Device\NamedPipe\f422aed9-6058-4bab-90b1-fe856bdcbd80 The unique identifier at the end will be different on your machine, and in fact, will be different every time you run the program. The

How do I deliver content from a WCF service as part of a web page? Web page content in this case typically refers to HTML, images, or other data that is directly consumed by the web browser rather than an application running in the web browser. There are a few things you need to do to make your web service serve up content in a way that's indistinguishable from an ordinary web server. I'll serve up a static image at a fixed location for this example but you can get as fancy as you'd like. The first

How do I write a contract for a wrapped message in the default namespace? I've written a quick sample to demonstrate what happens when you write the contract without taking any namespaces into account. [ServiceContract] public interface IService { [OperationContract] [WebInvoke(BodyStyle = WebMessageBodyStyle.Wrapped, UriTemplate = "/" )] void ProcessRequest( string data); } public class Service : IService { public void ProcessRequest( string data) { Console.WriteLine(OperationContext.Current.RequestContext.RequestMessage);

How do I force propagation of changes to information about a certificate revocation list after an update? A service is going to have several kinds of caching around the information that links the certificate to revocation information. The first kind of caching is based on the revocation mode of the certificate. A revocation mode of NoCheck disables checking on the certificate while a revocation mode of Offline directs checking to use a cached certificate revocation list. A revocation mode of Online

How do I find the address of a client connection to make a trust decision? Don't base security decisions on the perceived client address. Any address that we have comes from the underlying socket implementation and could be spoofed. The data that the socket has is sourced by the client. You should be using a source of information that has a verification process that the server trusts, such as a certificate, to distinguish clients. Next time: Reader Trends

Where can I get the IContextChannel that OperationContextScope requires? OperationContextScope allows you to create a temporary scope in which context for a service operation can build up before and after the operation is actually called. The constructor for OperationContextScope takes an instance of IContextChannel, which is a type that you've probably never seen before. Why are you expected to have this unknown type? It's because you have instances of it floating around all the time even though

How do I add SOAP headers to an outgoing request? There are a few different ways to add headers to a message depending on how you need to control the header content and where you need to insert the header. I like to think of these methods as being split among the application, the proxy, and the protocol. In your application code you can create an OperationContextScope around the request in order to change some of the request properties. Inside an OperationContextScope, you have a valid instance of