01 WCF编程概述
SOA的优点
什么是WCF
WCF
是微软分布式应用程序开发的集大成者,它整合了.Net平台下所有的和分布式系统有关的技术,如
Enterprise Sevices
(COM+).Net Remoting(一种非常有弹性的扩展性框架)、
Web Service(ASMX)、
WSE3.0
MSMQ消息队列。
以通信(Communiation)范围而论,它可以
跨进程、跨机器、跨子网、企业网乃至于 Internet;
以宿主程序而论,可以以
ASP.NET,EXE,WPF,Windows Forms,NT Service,COM+作为宿主(Host)
WCF可以支持的协议包括TCP,
HTTP,跨进程以及自定义,
安全模式则包括SAML, Kerberos,X509,用户/密码,
自定义等多种标准与模式。
也就是说,在WCF框架下,开发基于SOA的分布式系统变得容易了,微软将所有与此相关的技术要素都包含在内,掌握了WCF,就相当于掌握了叩开SOA大门的钥匙
WCF与webService是什么关系
ASP.NET Web Service:
利用Soap协议对象在分布式环境之间的数据交互。
WSDL来发布服务接口相关的描写。
称为WSE系列:
ASP.NET Web Service的安全,功能,数据加密、解密,托管宿主等多方面的伸展,
WCF宿主
static void Main(string[] args)
{
var baseAddress = ConfigurationManager.AppSettings["baseAddress"];
ApplicationService.Initialize();
MongoDBBootstrapper.Bootstrap(); using (ServiceHost orderService = new ServiceHost(typeof(OrderService), new Uri(string.Format("{0}/OrderService.svc", baseAddress))))
using (ServiceHost productService = new ServiceHost(typeof(ProductService), new Uri(string.Format("{0}/ProductService.svc", baseAddress))))
using (ServiceHost userService = new ServiceHost(typeof(UserService), new Uri(string.Format("{0}/UserService.svc", baseAddress))))
{
orderService.Open();
productService.Open();
userService.Open(); Console.WriteLine("Byteart Retail Services started at: {0}.", DateTime.Now);
Console.ReadLine();
Console.WriteLine("Byteart Retail Services stopped at: {0}.", DateTime.Now); orderService.Close();
productService.Close();
userService.Close();
}
}
<appSettings>
<add key="baseAddress" value="http://localhost:8559"/>
</appSettings>
服务端配置:
<system.serviceModel>
<extensions>
<behaviorExtensions>
<add name="unity" type="ByteartRetail.Infrastructure.UnityExtensions.UnityBehaviorExtensionElement, ByteartRetail.Infrastructure, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" />
</behaviorExtensions>
</extensions>
<behaviors>
<serviceBehaviors>
<behavior>
<serviceMetadata httpGetEnabled="true" />
<serviceDebug includeExceptionDetailInFaults="false" />
<unity operationContextEnabled="true" instanceContextEnabled="true" contextChannelEnabled="true" serviceHostBaseEnabled="true" />
</behavior>
</serviceBehaviors>
</behaviors>
<serviceHostingEnvironment aspNetCompatibilityEnabled="true" multipleSiteBindingsEnabled="true" />
</system.serviceModel>
另一种配置,
namespace Keasy5.WCF.WCFHost
{
class Program
{
static void Main(string[] args)
{
using (ServiceHost serviceHostPerCall = new ServiceHost(typeof(ServicePerCall)))
using (ServiceHost serviceHostPerSession = new ServiceHost(typeof(ServicePerSession)))
using (ServiceHost serviceHostSingle = new ServiceHost(typeof(ServiceSingle)))
{
serviceHostPerCall.Open();
serviceHostPerSession.Open();
serviceHostSingle.Open(); Console.WriteLine("所有服务已经启动: {0}.", DateTime.Now);
Console.ReadLine();
Console.WriteLine("所有服务已经关闭: {0}.", DateTime.Now); serviceHostPerCall.Close();
serviceHostPerSession.Close();
serviceHostSingle.Close();
}
}
}
}
对应的配置文件:
<?xml version="1.0" encoding="utf-8" ?>
<configuration> <system.web>
<compilation debug="true" />
</system.web>
<system.serviceModel>
<services>
<service name="Keasy5.WCF.WCFService.ServicePerCall" behaviorConfiguration="textserviceBehaviors">
<host>
<baseAddresses>
<add baseAddress = "http://localhost:5833/Keasy5.WCF.WCFService/ServicePerCall/" />
</baseAddresses>
</host>
<endpoint name="ServicePerCall" address="" binding="basicHttpBinding" contract="Keasy5.WCF.WCFService.IService1"></endpoint>
</service> <service name="Keasy5.WCF.WCFService.ServicePerSession" behaviorConfiguration="textserviceBehaviors">
<host>
<baseAddresses>
<add baseAddress = "http://localhost:5833/Keasy5.WCF.WCFService/ServicePerSession/" />
</baseAddresses>
</host>
<endpoint name="" address="" binding="basicHttpBinding" contract="Keasy5.WCF.WCFService.IService1"></endpoint>
</service> <service name="Keasy5.WCF.WCFService.ServiceSingle" behaviorConfiguration="textserviceBehaviors">
<host>
<baseAddresses>
<add baseAddress = "http://localhost:5833/Keasy5.WCF.WCFService/ServiceSingle/" />
</baseAddresses>
</host>
<endpoint name="ServiceSingle" address="" binding="basicHttpBinding" contract="Keasy5.WCF.WCFService.IService1"></endpoint>
</service>
</services>
<behaviors>
<serviceBehaviors >
<behavior name="textserviceBehaviors">
<serviceMetadata httpGetEnabled="True"/>
<serviceDebug includeExceptionDetailInFaults="True" />
</behavior>
</serviceBehaviors>
</behaviors>
</system.serviceModel> </configuration>
客户端调用
获取WCF服务的一个封装类:
ServiceProxy.cs
using System.ServiceModel; namespace ByteartRetail.Infrastructure.Communication
{
/// <summary>
/// 表示用于调用WCF服务的客户端服务代理类型。
/// </summary>
/// <typeparam name="T">需要调用的服务契约类型。</typeparam>
public sealed class ServiceProxy<T> : DisposableObject
where T : class, IApplicationServiceContract
{
#region Private Fields
private T client = null;
private static readonly object sync = new object();
#endregion #region Protected Methods
protected override void Dispose(bool disposing)
{
if (disposing)
lock (sync)
{
Close();
}
}
#endregion #region Public Properties
/// <summary>
/// 获取调用WCF服务的通道。
/// </summary>
public T Channel
{
get
{
lock (sync)
{
if (client != null)
{
var state = (client as IClientChannel).State;
if (state == CommunicationState.Closed)
client = null;
else
return client;
}
var factory = ChannelFactoryManager.Instance.GetFactory<T>();
client = factory.CreateChannel();
(client as IClientChannel).Open();
return client;
}
}
}
#endregion #region Public Methods
/// <summary>
/// 关闭并断开客户端通道(Client Channel)。
/// </summary>
/// <remarks>
/// 如果使用using语句对ServiceProxy进行了包裹,那么当程序执行点离开using的
/// 覆盖范围时,Close方法会被自动调用,此时客户端无需显式调用Close方法。反之
/// 如果没有使用using语句,那么则需要显式调用Close方法。
/// </remarks>
public void Close()
{
if (client != null)
((IClientChannel)client).Close();
}
#endregion
}
}
ChannelFactoryManager.cs
using System;
using System.Collections.Generic;
using System.ServiceModel; namespace ByteartRetail.Infrastructure.Communication
{
/// <summary>
/// 表示Channel Factory管理器。
/// </summary>
internal sealed class ChannelFactoryManager : DisposableObject
{
#region Private Fields
private static readonly Dictionary<Type, ChannelFactory> factories = new Dictionary<Type, ChannelFactory>();
private static readonly object sync = new object();
private static readonly ChannelFactoryManager instance = new ChannelFactoryManager();
#endregion #region Ctor
static ChannelFactoryManager() { }
private ChannelFactoryManager() { }
#endregion #region Public Properties
/// <summary>
/// 获取<c>ChannelFactoryManager</c>的单件(Singleton)实例。
/// </summary>
public static ChannelFactoryManager Instance
{
get { return instance; }
}
#endregion #region Protected Methods
protected override void Dispose(bool disposing)
{
if (disposing)
{
lock (sync)
{
foreach (Type type in factories.Keys)
{
ChannelFactory factory = factories[type];
try
{
factory.Close();
continue;
}
catch
{
factory.Abort();
continue;
}
}
factories.Clear();
}
}
}
#endregion #region Public Methods
/// <summary>
/// 获取与指定服务契约类型相关的Channel Factory实例。
/// </summary>
/// <typeparam name="T">服务契约的类型。</typeparam>
/// <returns>与指定服务契约类型相关的Channel Factory实例。</returns>
public ChannelFactory<T> GetFactory<T>()
where T : class, IApplicationServiceContract
{
lock (sync)
{
ChannelFactory factory = null;
if (!factories.TryGetValue(typeof(T), out factory))
{
factory = new ChannelFactory<T>(typeof(T).Name);
factory.Open();
factories.Add(typeof(T), factory);
}
return factory as ChannelFactory<T>;
}
}
#endregion
}
}
客户端调用:
using (ServiceProxy<IProductService> proxy = new ServiceProxy<IProductService>())
{
var categories = proxy.Channel.GetCategories(QuerySpec.Empty);
return View(categories);
}
客户端配置:
注意到ChannelFactoryManager类中创建工厂的方法:
public ChannelFactory<T> GetFactory<T>()
{
。。。。
factory = new ChannelFactory<T>(typeof(T).Name);
注意到ChannelFactoryManager类中创建工厂的方法,使用的是类型的名称typeof(T).Name)作为节点的配置名。
ChannelFactory<T>构造函数查看参数说明:
//
// 摘要:
// 使用指定的终结点配置名称初始化 System.ServiceModel.ChannelFactory<TChannel> 类的新实例。
//
// 参数:
// endpointConfigurationName:
// 用于终结点的配置名称。
//
// 异常:
// System.ArgumentNullException:
// endpointConfigurationName 为 null。
public ChannelFactory(string endpointConfigurationName);
故,客户端的配置EndPointd配置节点名要使用要用类型的名称,
<endpoint name="IProductService" 。。。
例如:
<endpoint name="IProductService" address="http://localhost:8558/ProductService.svc" contract="ByteartRetail.ServiceContracts.IProductService" binding="basicHttpBinding" bindingConfiguration="ServiceProxyBinding" />
客户端的配置:
<system.serviceModel>
<bindings>
<basicHttpBinding>
<binding name="ServiceProxyBinding" sendTimeout="00:10:00" receiveTimeout="00:10:00" closeTimeout="00:10:00" maxReceivedMessageSize="" maxBufferSize="">
<readerQuotas maxStringContentLength="" />
</binding>
</basicHttpBinding>
</bindings>
<client>
<endpoint name="IProductService" address="http://localhost:8558/ProductService.svc" contract="ByteartRetail.ServiceContracts.IProductService" binding="basicHttpBinding" bindingConfiguration="ServiceProxyBinding" />
<endpoint name="IOrderService" address="http://localhost:8558/OrderService.svc" contract="ByteartRetail.ServiceContracts.IOrderService" binding="basicHttpBinding" bindingConfiguration="ServiceProxyBinding" />
<endpoint name="IUserService" address="http://localhost:8558/UserService.svc" contract="ByteartRetail.ServiceContracts.IUserService" binding="basicHttpBinding" bindingConfiguration="ServiceProxyBinding" />
<endpoint name="IPostbackService" address="http://localhost:8558/PostbackService.svc" contract="ByteartRetail.ServiceContracts.IPostbackService" binding="basicHttpBinding" bindingConfiguration="ServiceProxyBinding" />
</client>
</system.serviceModel>