Connecting Azure Service Bus Relay (WCF endpoint) using HttpWebRequest

Question

Help Please. I was trying to access WCF service exposed to a service bus relay endpoint using HttpWebRequest.

I successfully got a token from ACS via OAuth WRAP Protocol. Using that token as a authorization in a request header, I created a WebRequest to communicate with the WCF service with an endpoint configured as WebHttpRelayBinding and a WCF service method applied with OperationContractAttribute and WebGetAttribute.

When I run the client application I got following error:

The message with To ' https://namespace.servicebus.windows.net/Student/GetInfo/GetStudentInfo/1 ' cannot be processed at the receiver, due to an AddressFilter mismatch at the EndpointDispatcher. Check that the sender and receiver's EndpointAddresses agree.

I googled and found a suggestion to apply following attribute to the service class:

[ServiceBehavior(AddressFilterMode = AddressFilterMode.Any)]

Although this resolved the previous error, but now the client application is ending up with following error:

The message with Action 'GET' cannot be processed at the receiver, due to a ContractFilter mismatch at the EndpointDispatcher. This may be because of either a contract mismatch (mismatched Actions between sender and receiver) or a binding/security mismatch between the sender and the receiver. Check that sender and receiver have the same contract and the same binding (including security requirements, eg Message, Transport, None).

I think I am missing something on the WCF service side. Sharing both client and service code for your review.

WCF Service Code:

[ServiceContract]
interface IStudentInfo
{
    [OperationContract]
    [WebGet(ResponseFormat = WebMessageFormat.Xml, UriTemplate = "/GetStudentInfo/{studentId}")]
    string GetStudentInfo(string studentId);
}

        [ServiceBehavior(AddressFilterMode = AddressFilterMode.Any)]
        private class StudentInfo : IStudentInfo
        {
            string IStudentInfo.GetStudentInfo(string studentId)
            {
                string returnString = null;

                // .....

                return returnString;
            }
        }

        public void Run()
        {
            Console.WriteLine("LISTENER");
            Console.WriteLine("========");

            string serviceNamespace = "namespace";
            string issuerName = "owner";
            string issuerKey = "key";
            string servicePath = "Student/GetInfo";

            ServiceHost sh = new ServiceHost(typeof(StudentInfo));

            // Binding
            WebHttpRelayBinding binding2 = new WebHttpRelayBinding();

            Uri uri = ServiceBusEnvironment.CreateServiceUri(Uri.UriSchemeHttps, serviceNamespace, servicePath);
            Console.WriteLine("Service Uri: " + uri);
            Console.WriteLine();

            sh.AddServiceEndpoint(typeof(IStudentInfo), binding2, uri);

            // Create the ServiceRegistrySettings behavior for the endpoint.
            var serviceRegistrySettings = new ServiceRegistrySettings(DiscoveryType.Public);

            // Create the shared secret credentials object for the endpoint matching the 
            // Azure access control services issuer 
            var sharedSecretServiceBusCredential = new TransportClientEndpointBehavior()
            {
                TokenProvider = TokenProvider.CreateSharedSecretTokenProvider(issuerName, issuerKey)
            };

            // Add the service bus credentials to all endpoints specified in configuration.
            foreach (var endpoint in sh.Description.Endpoints)
            {
                endpoint.Behaviors.Add(serviceRegistrySettings);
                endpoint.Behaviors.Add(sharedSecretServiceBusCredential);
            }

            sh.Open();

            Console.WriteLine("Press ENTER to close");
            Console.ReadLine();

            sh.Close();
        }

Service Consuming Code:

    static void Main(string[] args)
    {
        var studentId = "1";

        string _token = GetToken();
        Console.WriteLine(_token);

        // Create and configure the Request
        var httpWebRequest = (HttpWebRequest)WebRequest.Create("https://namespace.servicebus.windows.net/Student/GetInfo/GetStudentInfo/" + studentId);
        httpWebRequest.ContentType = "text/json";
        httpWebRequest.Method = "GET";
        httpWebRequest.Headers.Add(HttpRequestHeader.Authorization, string.Format("WRAP access_token=\"{0}\"", _token));

        // Get the response using the Request
        HttpWebResponse response = httpWebRequest.GetResponse() as HttpWebResponse;

        // Read the stream from the response object
        Stream stream = response.GetResponseStream();
        StreamReader reader = new StreamReader(stream);

        // Read the result from the stream reader
        string result = reader.ReadToEnd();

        Console.WriteLine("Result: " + result);

        Console.ReadLine();
    }

    static string GetToken()
    {
        string base_address = string.Format("https://namespace-sb.accesscontrol.windows.net");
        string wrap_name = "owner";
        string wrap_password = "key";
        string wrap_scope = "http://namespace.servicebus.windows.net/";

        WebClient client = new WebClient();
        client.BaseAddress = base_address;

        NameValueCollection values = new NameValueCollection();
        values.Add("wrap_name", wrap_name);
        values.Add("wrap_password", wrap_password);
        values.Add("wrap_scope", wrap_scope);

        byte[] responseBytes = client.UploadValues("WRAPv0.9", "POST", values);
        string response = Encoding.UTF8.GetString(responseBytes);

        string token = response.Split('&')
         .Single(value => value.StartsWith("wrap_access_token="))
         .Split('=')[1];

        string _token = HttpUtility.UrlDecode(token);

        return _token;
    }

Answer 1

Finally it's done!

I was missing a WebHttpBehavior to the endpoint that is necessary to expose WCF service as a REST endpoint.

endpoint.Behaviors.Add(new WebHttpBehavior());

Or alternatively I may host a service in WebServiceHost instead of a `ServiceHost' to enable REST binding to work.

WebServiceHost sh = new WebServiceHost(typeof(StudentInfo));