WCF 使用 MessageInspector 拦截消息

Question

我正在编写一个 WCF 服务（.NET Framework），该服务应该充当向其发送消息的客户端的提供者（仅限单向通信）。服务必须使用SOAP 协议进行通信。对服务提供商的要求之一是创建自定义 HTTP 响应，其正文将包含 SOAP 错误，如 w3c 标准中所述。 我想我会尝试使用MessageInspector类来达到这个目的，但是我无法达到预期的效果。我尝试根据文档（

https://learn.microsoft.com/en-us/dotnet/framework/wcf/samples/message-inspectors?redirectedfrom=MSDN

）实现必要的方法和配置，但到目前为止没有效果。 目前，该服务由 .NET Framework 控制台应用程序托管。以下是最重要元素的实现和项目结构：

结构：

---

MyService
DTO
-- CompositeType.cs
Utils
-- SchemaValidationBehavior.cs
-- SchemaValidationBehaviorExtensionElement.cs
-- SchemaValidationMessageInspector.cs
-- ValidationFault.cs
App.config
IMyService
MyService

实施：

---

    [ServiceContract]
    public interface IMyService
    {
        [OperationContract(IsOneWay = true)]
        void SendData(CompositeType composite);

    }

    public class MyService : IMyService
    {
        public void SendData(CompositeType composite)
        {
            System.Diagnostics.Debugger.Break();
            Console.WriteLine(composite.BoolValue.ToString() + " " + composite.StringValue);
        }
    }

    class SchemaValidationMessageInspector : IClientMessageInspector, IDispatchMessageInspector
    {
        XmlSchemaSet schemaSet;
        bool validateRequest;
        bool validateReply;
        bool isClientSide;
        [ThreadStatic] // Wskazuje, że wartość pola statycznego jest unikalna dla każdego wątku
        bool isRequest;

        public SchemaValidationMessageInspector()
        {
        }

        public SchemaValidationMessageInspector(XmlSchemaSet schemaSet, bool validateRequest, bool validateReply, bool isClientSide)
        {
            this.schemaSet = schemaSet;
            this.validateRequest = validateRequest;
            this.validateReply = validateReply;
            this.isClientSide = isClientSide;
        }

        // IClientMessageInspector Interfaces -- Client message inspector
        public void AfterReceiveReply(ref Message reply, object correlationState)
        {
            Console.WriteLine("I am inside AfterReceiveReply");
        }

        public object BeforeSendRequest(ref Message request, IClientChannel channel)
        {
            Console.WriteLine("I am inside BeforeSendRequest");
            return null;
        }

        // IDispatchMessageInspector Interfaces -- Service message inspector
        public object AfterReceiveRequest(ref Message request, IClientChannel channel, InstanceContext instanceContext)
        {
            Console.WriteLine("I am inside AfterReceiveRequest");
            return null;
        }

        public void BeforeSendReply(ref Message reply, object correlationState)
        {
            Console.WriteLine("I am inside BeforeSendReply");
        }
    }

    class SchemaValidationBehavior : IEndpointBehavior
    {
        XmlSchemaSet schemaSet;
        bool validateRequest;
        bool validateReply;

        public SchemaValidationBehavior(){}

        public SchemaValidationBehavior(XmlSchemaSet schemaSet, bool inspectRequest, bool inspectReply)
        {
            this.schemaSet = schemaSet;
            this.validateReply = inspectReply;
            this.validateRequest = inspectRequest;
        }

        #region IEndpointBehavior Members

        public void AddBindingParameters(ServiceEndpoint endpoint, BindingParameterCollection bindingParameters){}

        public void ApplyClientBehavior(ServiceEndpoint endpoint, ClientRuntime clientRuntime)
        {
            Console.WriteLine("I am inside ApplyClientBehavior");
        }

        public void ApplyDispatchBehavior(ServiceEndpoint endpoint, EndpointDispatcher endpointDispatcher)
        {
            Console.WriteLine("I am inside ApplyDispatchBehavior");
            SchemaValidationMessageInspector inspector = new SchemaValidationMessageInspector();
            endpointDispatcher.DispatchRuntime.MessageInspectors.Add(inspector);
        }

        public void Validate(ServiceEndpoint endpoint){}

        #endregion
    }

    public class SchemaValidationBehaviorExtensionElement : BehaviorExtensionElement
    {
        public SchemaValidationBehaviorExtensionElement(){}

        public override Type BehaviorType
        {
            get
            {
                return typeof(SchemaValidationBehavior);
            }
        }

        protected override object CreateBehavior()
        {
            Console.WriteLine("I am inside ApplyClientBehavior");
            return new SchemaValidationBehavior();
        }

        [ConfigurationProperty("validateRequest", DefaultValue = false, IsRequired = false)]
        public bool ValidateRequest
        {
            get { return (bool)base["validateRequest"]; }
            set { base["validateRequest"] = value; }
        }

        [ConfigurationProperty("validateReply", DefaultValue = false, IsRequired = false)]
        public bool ValidateReply
        {
            get { return (bool)base["validateReply"]; }
            set { base["validateReply"] = value; }
        }

    }

配置：

---

<configuration>
    <appSettings>
        <add key="aspnet:UseTaskFriendlySynchronizationContext" value="true" />
    </appSettings>
    <system.web>
        <compilation debug="true" />
    </system.web>
    
    <system.serviceModel>

<!-- SERVICES -->
        <services>
            <service name="MyService.MyService" behaviorConfiguration="MyServiceBehavior">
                <endpoint address="" binding="basicHttpBinding" contract="MyService.IMyService" behaviorConfiguration="MyEndpointBehavior">
                    <identity>
                        <dns value="localhost" />
                    </identity>
                </endpoint>
                <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange" />
                
                <host>
                    <baseAddresses>
                        <add baseAddress="http://localhost:9000/MyService/" />
                    </baseAddresses>
                </host>
            </service>
        </services>
<!-- SERVICES -->
        
<!-- BEHAVIORS -->      
        <behaviors>
            <endpointBehaviors>
                <behavior name="MyEndpointBehavior">
                    <schemaValidator validateRequest="true" validateReply="true"/>
                </behavior>
            </endpointBehaviors>

            <serviceBehaviors>
                <behavior name="MyServiceBehavior">
                    <serviceMetadata httpGetEnabled="true" httpsGetEnabled="true" />
                    <serviceDebug includeExceptionDetailInFaults="true" />
                    <!-- Add the behavior extension here -->
                </behavior>
            </serviceBehaviors>
        </behaviors>
<!-- BEHAVIORS -->

<!-- EXTENSIONS -->
        <extensions>
            <behaviorExtensions>
                <add name="schemaValidator" type="MyService.Utils.SchemaValidationBehaviorExtensionElement, MyService" />
            </behaviorExtensions>
        </extensions>
<!-- EXTENSIONS -->
        
    </system.serviceModel>
</configuration>

我一定缺少一些配置，或者可能配置错误，但从客户端发送的消息直接发送到 MyService 类的 SendData() 方法。

附注我想这并不重要，但这是 Host App 的代码：

---

    internal class Program
    {
        static void Main(string[] args)
        {
            ServiceHost host = null;

            try
            {
                host = new ServiceHost(typeof(MyService.MyService));
                host.Open();
                Console.WriteLine($"Host for MyService started @ {DateTime.Now} {Environment.NewLine}Service hosted on http://localhost:9000");

                Console.ReadLine();
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.ToString());
                Console.ReadLine();
            }
            finally
            {
                host?.Close();
            }
        }
    }

Answer 1

我尝试在主机的 App.config 文件中添加所有必要的配置 - 它发挥了作用 - 所有消息检查器方法都在消息到达目标方法之前被调用！