通过实现 IWsdlExporteExtension 具有选择性端点的 WCF 服务 WSDL 定义

Question

我有一个有两个端点的服务：

<service name="WcfService4.Service1">
    <endpoint bindingConfiguration="myBinding"
              contract="WcfService4.IService1"
              binding="basicHttpBinding">
    </endpoint>
    <endpoint name="wsEndpoint"
              contract="WcfService4.IService1"
              binding="wsHttpBinding">
    </endpoint>
<service>

此服务将由 Framework 2.0 和 4.0 客户端使用。从 2.0 客户端添加 Web 服务引用时一切正常。当我从 4.0 客户端添加服务引用时，会创建两个端点，使客户端指定它要使用的端点。

我想要实现的是让用户可以选择下载：服务的 basicHttpBinding 端点或 wsHttpBinding 端点，但不能同时下载，因此框架 4.0 客户端默认只有一个端点。

默认情况下，检索 wsdl 定义的路径是：

http://[server]:8080/MyApp/service.svc?wsdl

是否可以在另一个 url 上提供 wsdl 定义？：

例如：

http://[服务器]:8080/service.svc/basic?wsdl
http://[服务器]:8080/service.svc/ws?wsdl

通过使用 IWsdlExportExtension 实现来实现自定义端点行为，我可能会根据请求隐藏端点以防止被导出。

我想知道这是否可能，我的方法是否正确，或者我是否完全错误，或者无法做到这一点，因为我让事情变得有点复杂。谢谢

Answer 1

AFAIK 在 WSDL 导出扩展上，您没有收到发起 WSDL 创建过程的请求。但是您可以通过使用非 SOAP（也称为 REST）端点来公开 WSDL 来做到这一点。在此示例中，它只是向服务本身发送一个 HTTP 请求以获取 WSDL，然后“修剪”未请求的端点的结果 WSDL (XML)。

运行这段代码后，如果你运行

svcutil http://localhost:8000/service/conditionalwsdl/getwsdl?endpoint=basic

你只会得到BasicHttpBinding的端点，而如果你运行

svcutil http://localhost:8000/service/conditionalwsdl/getwsdl?endpoint=ws

您只能通过WSHttpBinding 获得端点。

public class StackOverflow_15434117
{
    [ServiceContract]
    public interface ITest
    {
        [OperationContract]
        string Echo(string text);
    }
    [ServiceContract]
    public interface IConditionalMetadata
    {
        [WebGet]
        XmlElement GetWSDL(string endpoint);
    }
    public class Service : ITest, IConditionalMetadata
    {
        public string Echo(string text)
        {
            return text;
        }

        public XmlElement GetWSDL(string endpoint)
        {
            WebClient c = new WebClient();
            string baseAddress = OperationContext.Current.Host.BaseAddresses[0].ToString();
            byte[] existingMetadata = c.DownloadData(baseAddress + "?wsdl");
            XmlDocument doc = new XmlDocument();
            doc.Load(new MemoryStream(existingMetadata));
            XmlElement result = doc.DocumentElement;
            XmlNamespaceManager nsManager = new XmlNamespaceManager(doc.NameTable);
            nsManager.AddNamespace("wsdl", "http://schemas.xmlsoap.org/wsdl/");
            nsManager.AddNamespace("soap11", "http://schemas.xmlsoap.org/wsdl/soap/");
            nsManager.AddNamespace("soap12", "http://schemas.xmlsoap.org/wsdl/soap12/");

            List<XmlNode> toRemove = new List<XmlNode>();

            // Remove all SOAP 1.1 endpoints which are not the requested one
            XmlNodeList toRemove11 = result.SelectNodes("//wsdl:service/wsdl:port/soap11:address", nsManager);
            XmlNodeList toRemove12 = result.SelectNodes("//wsdl:service/wsdl:port/soap12:address", nsManager);
            foreach (XmlNode node in toRemove11)
            {
                if (!node.Attributes["location"].Value.EndsWith(endpoint, StringComparison.OrdinalIgnoreCase))
                {
                    toRemove.Add(node);
                }
            }

            foreach (XmlNode node in toRemove12)
            {
                if (!node.Attributes["location"].Value.EndsWith(endpoint, StringComparison.OrdinalIgnoreCase))
                {
                    toRemove.Add(node);
                }
            }

            List<string> bindingsToRemove = new List<string>();
            foreach (XmlNode node in toRemove)
            {
                string binding;
                RemoveWsdlPort(node, out binding);
                bindingsToRemove.Add(binding);
            }

            toRemove.Clear();
            foreach (var binding in bindingsToRemove)
            {
                string[] parts = binding.Split(':');
                foreach (XmlNode node in result.SelectNodes("//wsdl:binding[@name='" + parts[1] + "']", nsManager))
                {
                    toRemove.Add(node);
                }
            }

            foreach (XmlNode bindingNode in toRemove)
            {
                bindingNode.ParentNode.RemoveChild(bindingNode);
            }

            return result;
        }

        static void RemoveWsdlPort(XmlNode wsdlPortDescendant, out string binding)
        {
            while (wsdlPortDescendant.LocalName != "port" && wsdlPortDescendant.NamespaceURI != "http://schemas.xmlsoap.org/wsdl/")
            {
                wsdlPortDescendant = wsdlPortDescendant.ParentNode;
            }

            binding = wsdlPortDescendant.Attributes["binding"].Value;

            var removed = wsdlPortDescendant.ParentNode.RemoveChild(wsdlPortDescendant);
        }
    }
    public static void Test()
    {
        string baseAddress = "http://" + Environment.MachineName + ":8000/Service";
        ServiceHost host = new ServiceHost(typeof(Service), new Uri(baseAddress));
        host.AddServiceEndpoint(typeof(ITest), new BasicHttpBinding(), "basic");
        host.AddServiceEndpoint(typeof(ITest), new WSHttpBinding(), "ws");
        host.AddServiceEndpoint(typeof(IConditionalMetadata), new WebHttpBinding(), "conditionalWsdl")
            .Behaviors.Add(new WebHttpBehavior());
        host.Description.Behaviors.Add(new ServiceMetadataBehavior { HttpGetEnabled = true });
        host.Open();
        Console.WriteLine("Host opened");

        ChannelFactory<ITest> factory = new ChannelFactory<ITest>(new BasicHttpBinding(), new EndpointAddress(baseAddress + "/basic"));
        ITest proxy = factory.CreateChannel();
        Console.WriteLine(proxy.Echo("Hello"));

        ((IClientChannel)proxy).Close();
        factory.Close();

        Console.WriteLine("Press ENTER to close the host");
        Console.ReadLine();
        host.Close();
    }
}