返回数据的WCF CommunicationException

Question

在这里，我们已经开发了一个可以从外部到达的SOAP。因为API的需求之一发生了变化，所以我想向这个API中添加一个新的类，以便为某些函数调用生成正确的路径。

我们的API分为三个独立的库：

• 一个用于对象
• 一个用于接口
• 一项用于执行。

当然，客户端可以在脚本中使用前两个，服务器拥有所有这三个。

我希望添加到API中的类如下所示：

namespace TenForce.Execution.API.Objects.Helpers
{
/// <summary>
/// <para>This interface defines the functionality available in the PathHelper for the API.</para>
/// </summary>
public interface IPathHelper
{
    string ApplicationFolder { get; }   // The HomeDataFolder for the application
    string CompanyHomeFolder { get; }   // The HomeDataFolder for the company.
    string CustomFolder { get; }        // The custom folder for professional services.
    string WikiFolder { get; }          // The WIKI folder to store pages.
    string AddinsFolder { get; }        // The AddinFolder to access the addins.
}
}

实际的类实现如下所示：

using System.IO;
using System.Runtime.Serialization;
using TenForce.Execution.BUL;
using TenForce.Execution.Framework;

namespace TenForce.Execution.API.Implementation.Helpers
{
/// <summary>
/// <para>This class provides a direct implementation of the IPathHelper for the API implementation
/// and manages all the paths inside the DataHomeFolder structure for the TenForce application.</para>
/// </summary>
[DataContract]
public class PathHelper : Objects.Helpers.IPathHelper
{
    #region Private Fields

    private readonly ParameterBUL _mParameterBul;
    private const Parameter.ParameterId DataHomeFolderId = Parameter.ParameterId.DataHomeFolder;
    private const Parameter.ParameterId CompanyNameId = Parameter.ParameterId.CompanyName;

    #endregion

    #region Constructor

    /// <summary>
    /// <para>Creates a new instance of the PathHelper class</para>
    /// </summary>
    public PathHelper()
    {
        _mParameterBul = new ParameterBUL();
    }

    #endregion

    #region IPathHelper Members

    /// <summary>
    /// <para>Returns the absolute path to the DataHomeFolder of the TenForce Application.</para>
    /// </summary>
    [DataMember]
    public string ApplicationFolder
    {
        get
        {
            return CreatePath(_mParameterBul.GetParameterValue(DataHomeFolderId));
        }
    }

    /// <summary>
    /// <para>Returns the absolute path to the Company DataHomeFolder.</para>
    /// </summary>
    [DataMember]
    public string CompanyHomeFolder
    {
        get
        {
            return CreatePath(Path.Combine(ApplicationFolder, _mParameterBul.GetParameterValue(CompanyNameId)));
        }
    }

    /// <summary>
    /// <para>Returns the absolute path to the Company custom folder.</para>
    /// </summary>
    [DataMember]
    public string CustomFolder
    {
        get
        {
            return CreatePath(Path.Combine(CompanyHomeFolder, @"custom"));
        }
    }

    /// <summary>
    /// <para>Returns the absolute path to the Company wiki folder.</para>
    /// </summary>
    [DataMember]
    public string WikiFolder
    {
        get
        {
            return CreatePath(Path.Combine(CompanyHomeFolder, @"wiki"));
        }
    }

    /// <summary>
    /// <para>Returns the absolute path to the Company addins folder.</para>
    /// </summary>
    [DataMember]
    public string AddinsFolder
    {
        get
        {
            return CreatePath(Path.Combine(CompanyHomeFolder, @"addins"));
        }
    }

    #endregion

    #region Private Members

    /// <summary>
    /// <para>Checks if the specified path exists, and creates the path 
    /// if the system cannot find it.</para>
    /// </summary>
    /// <param name="path">The path to verify.</param>
    private static string CreatePath(string path)
    {
        if (!Directory.Exists(path))
            Directory.CreateDirectory(path);
        return path;
    }

    #endregion
}
}

所有这些都是非常基本的东西。WCF服务是由我们使用通过.NET提供的工厂和类动态创建的，WCF服务非常适合服务中已经存在的所有代码。

因此，我决定在类(这是我们的服务)中添加以下一行：

    /// <summary>
    /// <para>Returns the PathHelper to construct the various paths for API Scripts.</para>
    /// </summary>
    /// <returns>An instance of the PathHelper.</returns>
    public Objects.Helpers.IPathHelper GetPathHelper()
    {
        return new Helpers.PathHelper();
    }

    #endregion

当我运行unittest时，除了检查PathHelper函数的测试之外，所有测试都正常工作，它们最终都得到了相同的错误消息/异常：

错误1 'TenForce.Execution.API.ImplementationTest/HelperTests/CheckApplicationFolderPath‘TestCase失败:执行System.ServiceModel.CommunicationException:远程端点不再识别此序列。这很可能是由于远程端点上的中止造成的。wsrm:标识符的值不是已知的序列标识符。可靠的会话失败了。 服务器堆栈跟踪:在System.ServiceModel.Channels.ReliableRequestSessionChannel.SyncRequest.WaitForReply(TimeSpan超时)在System.ServiceModel.Channels.RequestChannel.Request(Message消息，TimeSpan超时)在System.ServiceModel.Dispatcher.RequestChannelBinder.Request(Message消息，TimeSpan超时)在System.ServiceModel.Channels.ServiceChannel.Call(String操作，布尔单向操作，ProxyOperationRuntime操作，Object[] ins，Object[]超时，TimeSpan超时)在System.ServiceModel.Channels.ServiceChannel.Call(String操作，布尔单向操作，ProxyOperationRuntime操作，Object[] ins，( System.ServiceModel.Channels.ServiceChannelProxy.InvokeService(IMethodCallMessage methodCall，ProxyOperationRuntime操作)在System.ServiceModel.Channels.ServiceChannelProxy.Invoke(IMessage消息上) 异常重新引发: at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg，IMessage retMsg) at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData，( TenForce.Execution.API.Contracts.IAPI.GetPathHelper() at TenForce.Execution.API.ServiceClient.ServiceAPI.GetPathHelper() at c:\Users\arne.de.herdt\Documents\Trunk\Robinson\TenForce.Execution.API.ServiceClient\ServiceAPI.cs:line 163 at TenForce.Execution.API.ImplementationTest.HelperTests.CheckApplicationFolderPath() in C:\Users\arne.de.herdt\Documents\Trunk\Robinson\TenForce.Execution.API.ImplementationTest\HelperTests.cs:line 56 c：\Users\arne.de.herdt\Documents\Trunk\Robinson\TenForce.Execution.API.ServiceClient\ServiceAPI.cs 163

我不知道哪里出了问题，或者我错过了什么。代码正在为已经存在的代码工作，但是当我添加我的部分时，它变得混乱了，但是现有的函数仍然在工作。是我造成的麻烦。

Answer 1

由于来自注释和awnser的反馈，解决方案是将类移动到第二个API实现，而不是通过WCF服务使其变得更容易实现。

类包含函数和只读属性，因此WCF服务不能序列化该类。最终的结果将是只有脚本才能使用它，而不是服务。

Answer 2

这个错误在我看来很奇怪，可能与您动态生成服务的方式有关。

但是，该类是不可序列化的，该类上的属性是只读的(没有集合访问器)。要将属性标记为DataMember，属性需要有一个集合访问器，即使它被标记为私有。来自MSDN：

注已应用DataMemberAttribute属性的属性必须同时具有get字段和set字段；它们不能仅获取或仅设置。

DataMember文档

您可能希望在该类中序列化的唯一东西是m_ParameterBul变量，因此将其标记为DataMember并从只读属性中删除所有其他DataMember属性即可。

您应该注意，如果m_ParameterBul不依赖于服务器，则不需要在服务器端创建该类，因为所有内容都与客户端相关。在这种情况下，您应该直接在客户端上创建它。

希望能帮上忙！

/// <summary>
/// <para>This class provides a direct implementation of the IPathHelper for the API implementation
/// and manages all the paths inside the DataHomeFolder structure for the TenForce application.</para>
/// </summary>
[DataContract]
public class PathHelper : Objects.Helpers.IPathHelper
{
    #region Private Fields
    [DataMember]
    private readonly ParameterBUL _mParameterBul;
    private const Parameter.ParameterId DataHomeFolderId = Parameter.ParameterId.DataHomeFolder;
    private const Parameter.ParameterId CompanyNameId = Parameter.ParameterId.CompanyName;

    #endregion

    #region Constructor

    /// <summary>
    /// <para>Creates a new instance of the PathHelper class</para>
    /// </summary>
    public PathHelper()
    {
        _mParameterBul = new ParameterBUL();
    }

    #endregion

    #region IPathHelper Members

    /// <summary>
    /// <para>Returns the absolute path to the DataHomeFolder of the TenForce Application.</para>
    /// </summary>   
    public string ApplicationFolder
    {
        get
        {
            return CreatePath(_mParameterBul.GetParameterValue(DataHomeFolderId));
        }
    }

    /// <summary>
    /// <para>Returns the absolute path to the Company DataHomeFolder.</para>
    /// </summary>   
    public string CompanyHomeFolder
    {
        get
        {
            return CreatePath(Path.Combine(ApplicationFolder, _mParameterBul.GetParameterValue(CompanyNameId)));
        }
    }

    /// <summary>
    /// <para>Returns the absolute path to the Company custom folder.</para>
    /// </summary>
    public string CustomFolder
    {
        get
        {
            return CreatePath(Path.Combine(CompanyHomeFolder, @"custom"));
        }
    }

    /// <summary>
    /// <para>Returns the absolute path to the Company wiki folder.</para>
    /// </summary>
    public string WikiFolder
    {
        get
        {
            return CreatePath(Path.Combine(CompanyHomeFolder, @"wiki"));
        }
    }

    /// <summary>
    /// <para>Returns the absolute path to the Company addins folder.</para>
    /// </summary>    
    public string AddinsFolder
    {
        get
        {
            return CreatePath(Path.Combine(CompanyHomeFolder, @"addins"));
        }
    }

    #endregion

    #region Private Members

    /// <summary>
    /// <para>Checks if the specified path exists, and creates the path 
    /// if the system cannot find it.</para>
    /// </summary>
    /// <param name="path">The path to verify.</param>
    private static string CreatePath(string path)
    {
        if (!Directory.Exists(path))
            Directory.CreateDirectory(path);
        return path;
    }

    #endregion
}