WCF错误:服务器没有提供有意义的回复;

Question

请有人帮助我找出发生的事情.我有我的WCF服务工作正常,现在突然我有这个错误:

服务器没有提供有意义的回复; 这可能是由于合同不匹配,过早的会话关闭或内部服务器错误造成的

我必须告诉它,当我选择数千条记录时它仍然可以工作,但是当数据很大时我会收到这个错误,尽管它之前工作正常!

    private static string ConnString = "Server=127.0.0.1; Port=5432; Database=DBname; User Id=UName; Password=MyPassword;"
    DataTable myDT = new DataTable();

                NpgsqlConnection myAccessConn = new NpgsqlConnection(ConnString);
                myAccessConn.Open();
        string query = "SELECT * FROM Twitter";

                NpgsqlDataAdapter myDataAdapter = new NpgsqlDataAdapter(query, myAccessConn);

                myDataAdapter.Fill(myDT);
                foreach (DataRow dr in myDT.Rows)
                {
   **WHEN I HAVE TOO MANY RECORDS IT STOPS HERE**
        ...

web.config中

<configuration>
    <system.web>
        <compilation debug="false" targetFramework="4.0" />
      <httpRuntime maxRequestLength="2147483647" executionTimeout="100000" />
    </system.web>
  <system.diagnostics>
    <trace autoflush="true" />
    <sources>
      <source name="System.ServiceModel"
              switchValue="Information, ActivityTracing"
              propagateActivity="true">
        <listeners>
          <add name="traceListener" type="System.Diagnostics.XmlWriterTraceListener" initializeData="Traces4.svclog"/>
        </listeners>
      </source>
    </sources>
  </system.diagnostics>
  <system.serviceModel>
        <bindings>
            <basicHttpBinding>
                <binding name="BasicHttpBinding_IDBService" closeTimeout="00:30:00"
                    openTimeout="00:30:00" receiveTimeout="00:30:00" sendTimeout="00:30:00"
                    allowCookies="false" bypassProxyOnLocal="false" hostNameComparisonMode="StrongWildcard"
                    maxBufferSize="2147483647" maxBufferPoolSize="2147483647" maxReceivedMessageSize="2147483647"
                    messageEncoding="Text" textEncoding="utf-8" transferMode="Streamed"
                    useDefaultWebProxy="true">
                    <readerQuotas maxDepth="2147483647" maxStringContentLength="2147483647" maxArrayLength="2147483647"
                        maxBytesPerRead="2147483647" maxNameTableCharCount="2147483647" />
                    <security mode="None">
                        <transport clientCredentialType="None" proxyCredentialType="None"
                            realm="" />
                        <message clientCredentialType="UserName" algorithmSuite="Default" />
                    </security>
                </binding>
            </basicHttpBinding>
        </bindings>
    <client>
      <endpoint address="" binding="basicHttpBinding" 
          bindingConfiguration="BasicHttpBinding_IDBService" contract="DBServiceReference.IDBService"
          name="BasicHttpBinding_IDBService" />
    </client>
        <behaviors>
            <serviceBehaviors>
                <behavior name="">
                  <serviceMetadata httpGetEnabled="true" />
                  <serviceDebug includeExceptionDetailInFaults="true" />
                  <dataContractSerializer maxItemsInObjectGraph="2147483646" />
                </behavior>
            </serviceBehaviors>
        </behaviors>
        <serviceHostingEnvironment aspNetCompatibilityEnabled="false" multipleSiteBindingsEnabled="true" />
    </system.serviceModel>
</configuration>

客户端配置(已编辑)

<configuration>
        <system.serviceModel>
            <bindings>
                <basicHttpBinding>
                    <binding name="BasicHttpBinding_IRouteService" maxBufferSize="2147483647"
                        maxReceivedMessageSize="2147483647">
                        <security mode="None" />
                    </binding>
                    <binding name="BasicHttpBinding_IDBService" closeTimeout="00:30:00"
                        openTimeout="00:30:00" receiveTimeout="00:30:00" sendTimeout="00:30:00"
                        maxBufferSize="2147483647" maxReceivedMessageSize="2147483647"
                        transferMode="Buffered" >

                        <security mode="None" />
                    </binding>
                </basicHttpBinding>
                <customBinding>
                    <binding name="CustomBinding_IRouteService">
                        <binaryMessageEncoding />
                        <httpTransport maxReceivedMessageSize="2147483647"
                            maxBufferSize="2147483647" />
                    </binding>
                </customBinding>
            </bindings>

            <client>
                <endpoint address="http://dev.virtualearth.net/webservices/v1/routeservice/routeservice.svc"
                    binding="basicHttpBinding" bindingConfiguration="BasicHttpBinding_IRouteService"
                    contract="BingRoutingService.IRouteService" name="BasicHttpBinding_IRouteService" />
                <endpoint address="http://dev.virtualearth.net/webservices/v1/routeservice/routeservice.svc/binaryHttp"
                    binding="customBinding" bindingConfiguration="CustomBinding_IRouteService"
                    contract="BingRoutingService.IRouteService" name="CustomBinding_IRouteService" />
                <endpoint address="" binding="basicHttpBinding" bindingConfiguration="BasicHttpBinding_IDBService"
                    contract="DBServiceReference.IDBService" name="BasicHttpBinding_IDBService" />
            </client>
        </system.serviceModel>
    </configuration>

在我的文件scvlog中,我没有任何异常!我没有任何其他想法我还能做些什么才能理解问题出在哪里.请有人帮帮我!!!

Answer 1

一个不同的答案,以防任何人到达这里,因为我一直在寻找问题的一般答案.

似乎执行驴工作的DataContractSerializer非常挑剔,但并不总是将真正的错误传递给客户端.服务器进程在发生故障后直接死亡 - 因此无法找到错误.在我的情况下,问题是用作标志的枚举,但没有用[Flags]属性(挑剔或什么!)装饰.

为了解决这个问题,我创建了一个序列化程序的实例并检查了调试器中的错误; 这是一个代码片段,因为我有它的手.

编辑:回应评论中的要求......

修改了代码片段以显示我现在使用的辅助方法.与以前大致相同,但是在一个方便的通用包装中.

public static T CheckCanSerialize<T>(this T returnValue) {
    var lDCS = new System.Runtime.Serialization.DataContractSerializer(typeof(T));

    Byte[] lBytes;
    using (var lMem1 = new IO.MemoryStream()) {
        lDCS.WriteObject(lMem1, returnValue);
        lBytes = lMem1.ToArray();
    }

    T lResult;
    using (var lMem2 = new IO.MemoryStream(lBytes)) {
        lResult = (T)lDCS.ReadObject(lMem2);
    }

    return lResult;
}

并且要使用它,而不是返回一个对象,在调用helper方法之后返回该对象,所以

public MyDodgyObject MyService() {
    ... do lots of work ...
    return myResult;
}

变

public MyDodgyObject MyService() {
    ... do lots of work ...
    return CheckCanSerialize(myResult);
}

然后在服务停止关注之前抛出序列化中的任何错误,因此可以在调试器中进行分析.

注意; 我不建议将调用留在生产代码中,它具有序列化和反序列化对象的开销,一旦代码被调试就没有任何实际好处.

希望这有助于某人 - 我浪费了大约3个小时试图追踪它.

Answer 2

我不知道它是否真的可以作为答案,但我已经尝试将web.config更改为<security mode="None" />,<security mode="Transport" />并且它工作了!!!

我想要注意,这部分应该只在web.config和客户端配置中更改仍然存在<security mode="None" />,因为在两者中运输它不起作用!

所以在那之后,我决定再次回来None security,它工作了几分钟,然后再次停止,它回来了错误:

服务器没有提供有意义的回复; 这可能是由于合同不匹配,过早的会话关闭或内部服务器错误造成的

所以我的情况似乎是在web.config中设置解决方案

security mode to Transport

Answer 3

就我而言,我正在开发一个与WCF Web服务通信的Windows应用程序项目.Web服务使用netTcpBinding返回一个Stream对象(图片).

由于Windows应用程序没有配置文件,因此默认值用于绑定.只需在客户端后端代码扩展MaxReceivedMessageSize就可以解决我的问题.

var API = new StreamService.StreamServiceClient(
  new System.ServiceModel.NetTcpBinding(System.ServiceModel.SecurityMode.None)
  {
    MaxReceivedMessageSize = 2147483647
  },
  new System.ServiceModel.EndpointAddress("net.tcp://machine/app/service.svc")
);