如何：动态更新

本主题概述了创建和动态更新路由配置所需的基本步骤。 在本示例中，从配置文件中获取初始路由配置，并将所有消息路由至 regularCalc 计算器服务；不过，本示例随后以编程方式更新该路由配置，以便更改 roundingCalc 服务的目标终结点。

注意

在许多实现中，配置完全是动态配置，而不依赖于默认配置；但在某些情况下（如本主题中的情况），启动服务时需要处于默认配置状态。

注意

动态更新仅在内存中进行，并且不会导致修改配置文件。

regularCalc 和 roundingCalc 均支持相同的加减乘除运算，区别是 roundingCalc 在返回所有计算结果前，会将计算结果舍入到最接近的整数值。 配置文件用于配置服务，以便将所有消息路由至 regularCalc 服务。 启动路由服务之后，将使用 ApplyConfiguration 重新配置此服务，以便将消息路由至 roundingCalc 服务。

实现初始配置

1. 指定由服务公开的服务终结点，创建基本路由服务配置。 下面的示例定义了一个用于接收消息的服务终结点， 还定义了一个用于将消息发送到 regularCalc 的客户端终结点。

   <services>
     <service behaviorConfiguration="routingConfiguration"
              name="System.ServiceModel.Routing.RoutingService">
       <host>
         <baseAddresses>
           <add baseAddress="http://localhost/routingservice/router" />
         </baseAddresses>
       </host>
       <!--Set up the inbound endpoint for the Routing Service-->
       <endpoint address="calculator"
                 binding="wsHttpBinding"
                 name="routerEndpoint"
                 contract="System.ServiceModel.Routing.IRequestReplyRouter" />
     </service>
   </services>
   <client>
   <!--set up the destination endpoint-->
     <endpoint name="regularCalcEndpoint"
               address="net.tcp://localhost:9090/servicemodelsamples/service/"
               binding="netTcpBinding"
               contract="*" />
   </client>
   

2. 定义用于将消息路由到目标终结点的筛选器。 在本示例中，使用 MatchAll 筛选器将所有消息路由至先前定义的 regularCalcEndpoint。 下面的示例定义了此筛选器和筛选器表。

   <filters>
     <!--define the message filter-->
     <filter name="MatchAllFilter" filterType="MatchAll"/>
   </filters>
   <filterTables>
     <filterTable name="filterTable1">
         <!--add the filter to the message filter table-->
         <add filterName="MatchAllFilter" endpointName="regularCalcEndpoint"/>
     </filterTable>
   </filterTables>
   

3. 若要根据筛选器表中包含的筛选器评估传入消息，必须使用路由行为将筛选器表与服务终结点关联。 下面的示例演示如何将“filterTable1”与服务终结点关联。

   <behaviors>
     <!--default routing service behavior definition-->
     <serviceBehaviors>
       <behavior name="routingConfiguration">
         <routing filterTableName="filterTable1" />
       </behavior>
     </serviceBehaviors>
   </behaviors>
   

实现动态配置

只能使用代码动态配置路由服务，方法是：新建 RoutingConfiguration，并用 ApplyConfiguration 替换当前配置。 在本示例中，路由服务自承载在控制台应用程序中。 启动应用程序之后，您可以在控制台窗口中输入“regular”或“rounding”来修改路由配置，以便配置消息将路由到的目标终结点；如果输入“regular”，则路由到 regularCalc；否则，如果输入“rounding”，则路由到 roundingCalc。

1. 必须添加以下 using 指令才能支持路由服务。

   using System;
   using System.Collections.Generic;
   using System.ServiceModel;
   using System.ServiceModel.Channels;
   using System.ServiceModel.Description;
   using System.ServiceModel.Dispatcher;
   using System.ServiceModel.Routing;
   

2. 下面的代码用作控制台应用程序来自承载路由服务。 此代码将使用上一步所述的配置来初始化路由服务，该配置包含在应用程序配置文件中。 while 循环包含用于更改路由配置的代码。

   // Host the service within this EXE console application.
   public static void Main()
   {
       // Create a ServiceHost for the CalculatorService type.
       using (ServiceHost serviceHost =
           new ServiceHost(typeof(RoutingService)))
       {
           // Open the ServiceHost to create listeners
           // and start listening for messages.
           Console.WriteLine("The Routing Service configured, opening....");
           serviceHost.Open();
           Console.WriteLine("The Routing Service is now running.");
            Console.WriteLine("Type 'quit' to terminate router.");
            Console.WriteLine("<ENTER> to change routing configuration.");
            while (Console.ReadLine() != "quit")
            {
           ....
           }
       }
   }
   

3. 若要动态更新路由配置，必须创建新的路由配置。 新路由配置必须包含它需要的所有终结点、筛选器和筛选器表，因为它将完全替换现有路由配置。 为了使用新路由配置，必须调用 ApplyConfiguration 并传递新配置。

   向以前定义的 while 循环添加以下代码，这样就允许根据用户输入重新配置此服务。

   Console.WriteLine("Enter 'regular' or 'rounding' to set the destination endpoint:");
   string destEndpoint = Console.ReadLine();
   // Create a new RoutingConfiguration
   RoutingConfiguration rc = new RoutingConfiguration();
   // Determine the endpoint to configure for
   switch (destEndpoint)
   {
       case "regular":
           // Define the destination endpoint
           ServiceEndpoint regularCalc = new ServiceEndpoint(
              ContractDescription.GetContract(typeof(IRequestReplyRouter)),
              new NetTcpBinding(),
              new EndpointAddress("net.tcp://localhost:9090/servicemodelsamples/service/"));
           // Create a MatchAll filter and add to the filter table
           rc.FilterTable.Add(new MatchAllMessageFilter(), new List<ServiceEndpoint> { regularCalc });
           // Use ApplyConfiguration to update the Routing Service
           serviceHost.Extensions.Find<RoutingExtension>().ApplyConfiguration(rc);
           Console.WriteLine("Applied new routing configuration.");
           break;
       case "rounding":
           // Define the destination endpoint
           ServiceEndpoint roundingCalc = new ServiceEndpoint(
              ContractDescription.GetContract(typeof(IRequestReplyRouter)),
              new NetTcpBinding(),
              new EndpointAddress("net.tcp://localhost:8080/servicemodelsamples/service/"));
           // Create a MatchAll filter and add to the filter table
           rc.FilterTable.Add(new MatchAllMessageFilter(), new List<ServiceEndpoint> { roundingCalc });
           // Use ApplyConfiguration to update the Routing Service
           serviceHost.Extensions.Find<RoutingExtension>().ApplyConfiguration(rc);
           Console.WriteLine("Applied new routing configuration.");
           break;
       default:
           Console.WriteLine("Incorrect value entered, no change.");
           break;
   }
   

   备注

   由于提供新 RoutingConfiguration 的方法包含在 RoutingExtension 服务扩展中，因此，在具有或可获取对 ServiceHost 或 ServiceExtensions 的引用的 WCF 扩展性模型中，可以在任意位置（例如，在另一 ServiceExtension 中）提供新的 RoutingConfiguration 对象。

示例 1

下面是此示例中使用的控制台应用程序的完整清单：

//-----------------------------------------------------------------
//  Copyright (c) Microsoft Corporation.  All Rights Reserved.
//-----------------------------------------------------------------

using System;
using System.Collections.Generic;
using System.ServiceModel;
using System.ServiceModel.Channels;
using System.ServiceModel.Description;
using System.ServiceModel.Dispatcher;
using System.ServiceModel.Routing;

namespace Microsoft.Samples.AdvancedFilters
{
    public class Router
    {
        // Host the service within this EXE console application.
        public static void Main()
        {
            // Create a ServiceHost for the CalculatorService type.
            using (ServiceHost serviceHost =
                new ServiceHost(typeof(RoutingService)))
            {
                // Open the ServiceHost to create listeners
                // and start listening for messages.
                Console.WriteLine("The Routing Service configured, opening....");
                serviceHost.Open();
                Console.WriteLine("The Routing Service is now running.");
                Console.WriteLine("Type 'quit' to terminate router.");
                Console.WriteLine("<ENTER> to change routing configuration.");
                while (Console.ReadLine() != "quit")
                {
                    Console.WriteLine("Enter 'regular' or 'rounding' to set the destination endpoint:");
                    string destEndpoint = Console.ReadLine();
                    // Create a new RoutingConfiguration
                    RoutingConfiguration rc = new RoutingConfiguration();
                    // Determine the endpoint to configure for
                    switch (destEndpoint)
                    {
                        case "regular":
                            // Define the destination endpoint
                            ServiceEndpoint regularCalc = new ServiceEndpoint(
                            ContractDescription.GetContract(typeof(IRequestReplyRouter)),
                            new NetTcpBinding(),
                            new EndpointAddress("net.tcp://localhost:9090/servicemodelsamples/service/"));
                            // Create a MatchAll filter and add to the filter table
                            rc.FilterTable.Add(new MatchAllMessageFilter(), new List<ServiceEndpoint> { regularCalc });
                            // Use ApplyConfiguration to update the Routing Service
                            serviceHost.Extensions.Find<RoutingExtension>().ApplyConfiguration(rc);
                            Console.WriteLine("Applied new routing configuration.");
                            break;
                        case "rounding":
                            // Define the destination endpoint
                            ServiceEndpoint roundingCalc = new ServiceEndpoint(
                                ContractDescription.GetContract(typeof(IRequestReplyRouter)),
                                new NetTcpBinding(),
                                new EndpointAddress("net.tcp://localhost:8080/servicemodelsamples/service/"));
                            // Create a MatchAll filter and add to the filter table
                            rc.FilterTable.Add(new MatchAllMessageFilter(), new List<ServiceEndpoint> { roundingCalc });
                            // Use ApplyConfiguration to update the Routing Service
                            serviceHost.Extensions.Find<RoutingExtension>().ApplyConfiguration(rc);
                            Console.WriteLine("Applied new routing configuration.");
                            break;
                        default:
                            Console.WriteLine("Incorrect value entered, no change.");
                            break;
                    }
                }
            }
        }
    }
}

示例 2

下面是此示例中使用的配置文件的完整清单：

<?xml version="1.0" encoding="utf-8" ?>
<!-- Copyright (c) Microsoft Corporation. All rights reserved -->
<configuration>
  <system.serviceModel>
    <services>
      <service behaviorConfiguration="routingConfiguration"
               name="System.ServiceModel.Routing.RoutingService">
        <host>
          <baseAddresses>
            <add baseAddress="http://localhost/routingservice/router" />
          </baseAddresses>
        </host>
        <!--Set up the inbound endpoint for the Routing Service-->
        <endpoint address="calculator"
                  binding="wsHttpBinding"
                  name="routerEndpoint"
                  contract="System.ServiceModel.Routing.IRequestReplyRouter" />
      </service>
    </services>
    <behaviors>
      <!--default routing service behavior definition-->
      <serviceBehaviors>
        <behavior name="routingConfiguration">
          <routing filterTableName="filterTable1" />
        </behavior>
      </serviceBehaviors>
    </behaviors>

    <client>
<!--set up the destination endpoint-->
      <endpoint name="regularCalcEndpoint"
                address="net.tcp://localhost:9090/servicemodelsamples/service/"
                binding="netTcpBinding"
                contract="*" />
    </client>
    <routing>

      <filters>
        <!--define the message filter-->
        <filter name="MatchAllFilter" filterType="MatchAll"/>
      </filters>
      <filterTables>
        <filterTable name="filterTable1">
            <!--add the filter to the message filter table-->
            <add filterName="MatchAllFilter" endpointName="regularCalcEndpoint"/>
        </filterTable>
      </filterTables>
    </routing>
  </system.serviceModel>
</configuration>

另请参阅

• 路由服务