在服务器端记录SOAP请求和响应

Question

我正在尝试为我的ASP.NET Web服务的所有SOAP方法调用创建一个日志记录服务.我一直在查看 来自控制台应用程序的Log SOAP消息以及MSDN上SOAP扩展的演练(http://msdn.microsoft.com/en-us/library/s25h0swd%28v=vs.100%29.aspx)但他们似乎并没有完全覆盖它.

我不想改变SOAP消息,只需将其记录到数据库表中即可.我正在尝试做的是读取SOAP消息流,将其解析为XML,记录XML并让调用以其快乐的方式进行.但是当我读取它时,它被花费/处理掉了.我已经尝试复制流内容以不中断流.

根据演练,该ProcessMessage方法应如下所示:

public override void ProcessMessage(SoapMessage message) 
{
   switch (message.Stage) 
   {
   case SoapMessageStage.BeforeSerialize:
       break;
   case SoapMessageStage.AfterSerialize:
       // Write the SOAP message out to a file.
       WriteOutput( message );
       break;
   case SoapMessageStage.BeforeDeserialize:
       // Write the SOAP message out to a file.
       WriteInput( message );
       break;
   case SoapMessageStage.AfterDeserialize:
       break;
   default:
       throw new Exception("invalid stage");
   }
}

我已经设法在BeforeDeserialize阶段期间解析流没有问题,但然后ProcessMessage在AfterSerialize阶段再次调用,然后使用流并且不再包含任何数据.

根据SOAP消息修改使用SOAP扩展(http://msdn.microsoft.com/en-us/library/esw638yk%28v=vs.100%29.aspx),SOAP调用将执行以下步骤:

服务器端接收请求消息并准备响应

1. Web服务器上的ASP.NET接收SOAP消息.
2. 在Web服务器上创建SOAP扩展的新实例.
3. 在Web服务器上,如果这是第一次在服务器端使用此Web服务执行此SOAP扩展,则会在服务器上运行的SOAP扩展上调用GetInitializer方法.
4. 调用Initialize方法.
5. 调用ChainStream方法.
6. 使用设置为BeforeDeserialize的 SoapMessageStage调用ProcessMessage方法.
7. ASP.NET反序列化XML中的参数.
8. 在SoapMessageStage设置为AfterDeserialize的情况下调用ProcessMessage方法.
9. ASP.NET创建实现Web服务的类的新实例,并调用Web服务方法,传入反序列化的参数.此对象与Web服务器驻留在同一台计算机上.
10. Web服务方法执行其代码,最终设置返回值和任何输出参数.
11. 在SoapMessageStage设置为BeforeSerialize的情况下调用ProcessMessage方法.
12. Web服务器上的ASP.NET将返回值和输出参数序列化为XML.
13. 使用设置为AfterSerialize的 SoapMessageStage调用ProcessMessage方法.
14. ASP.NET通过网络将SOAP响应消息发送回Web服务客户端.

正确执行步骤6并记录SOAP XML.然后,在服务器处理完呼叫之后,它应该不再做任何事情,完成它所需要的(步骤10),并返回响应(步骤13).相反,它会立即ProcessMessage在AfterSerialize阶段中再次调用,但这次流已经花费,并在我尝试记录时抛出异常.

根据演练我应该使用该ChainStream方法,它应该在上面的步骤5中运行.当我拨打电话时,它会运行两次,前BeforeDeserialize一次和前一次AfterSerialize.

我已经尝试将消息流复制到单独的流并将其用于日志记录,如果BeforeDeserialize已经运行,也设置某种状态,但问题仍然存在.

我仍然需要代码AfterSerialize来处理发送回客户端的响应.但是,如果我尝试删除我的代码AfterSerialize,只运行BeforeDeserialize' I get aHTTP 400中的代码:错误请求.

这一切都发生在实际的方法调用之前,所以我从来没有得到方法内的代码(步骤10).

Answer 1

我的解决方案是基于迈克布里奇的解决方案,但我不得不做一些改动.必须包含初始化程序,如果您尝试在不可用的阶段访问soap消息信息,则会抛出异常.

public class SoapLoggingExtension : SoapExtension
{
    private Stream _originalStream;
    private Stream _workingStream;
    private static String _initialMethodName;
    private static string _methodName;
    private static String _xmlResponse;

    /// <summary>
    /// Side effects: saves the incoming stream to
    /// _originalStream, creates a new MemoryStream
    /// in _workingStream and returns it.  
    /// Later, _workingStream will have to be created
    /// </summary>
    /// <param name="stream"></param>
    /// <returns></returns>
    public override Stream ChainStream(Stream stream)
    {

        _originalStream = stream;
        _workingStream = new MemoryStream();
        return _workingStream;
    }

    /// <summary>
    /// Process soap message
    /// </summary>
    /// <param name="message"></param>
    public override void ProcessMessage(SoapMessage message)
    {
        switch (message.Stage)
        {
            case SoapMessageStage.BeforeSerialize:
                break;

            case SoapMessageStage.AfterSerialize:
                //Get soap call as a xml string
                var xmlRequest = GetSoapEnvelope(_workingStream);
                //Save the inbound method name
                _methodName = message.MethodInfo.Name;
                CopyStream(_workingStream, _originalStream);
                //Log call
                LogSoapRequest(xmlRequest, _methodName, LogObject.Direction.OutPut);
                break;

            case SoapMessageStage.BeforeDeserialize:
                CopyStream(_originalStream, _workingStream);
                //Get xml string from stream before it is used
                _xmlResponse = GetSoapEnvelope(_workingStream);
                break;

            case SoapMessageStage.AfterDeserialize:
                //Method name is only available after deserialize
                _methodName = message.MethodInfo.Name;
                LogSoapRequest(_xmlResponse, _methodName, LogObject.Direction.InPut);
                break;
        }
    }

    /// <summary>
    /// Returns the XML representation of the Soap Envelope in the supplied stream.
    /// Resets the position of stream to zero.
    /// </summary>
    private String GetSoapEnvelope(Stream stream)
    {
        stream.Position = 0;
        StreamReader reader = new StreamReader(stream);
        String data = reader.ReadToEnd();
        stream.Position = 0;
        return data;
    }

    private void CopyStream(Stream from, Stream to)
    {
        TextReader reader = new StreamReader(from);
        TextWriter writer = new StreamWriter(to);
        writer.WriteLine(reader.ReadToEnd());
        writer.Flush();
    }

    public override object GetInitializer(Type serviceType)
    {
        return serviceType.FullName;
    }

    //Never needed to use this initializer, but it has to be implemented
    public override object GetInitializer(LogicalMethodInfo methodInfo, SoapExtensionAttribute attribute)
    {
        throw new NotImplementedException();
        //return ((TraceExtensionAttribute)attribute).Filename;
    }

    public override void Initialize(object initializer)
    {
        if (String.IsNullOrEmpty(_methodName))
        {
            _initialMethodName = _methodName;
            _waitForResponse = false;
        }
    }

    private void LogSoapRequest(String xml, String methodName, LogObject.Direction direction)
    {

        String connectionString = String.Empty;
        String callerIpAddress = String.Empty;
        String ipAddress = String.Empty;

        try
        {
            //Only log outbound for the response to the original call
            if (_waitForResponse && xml.IndexOf("<" + _initialMethodName + "Response") < 0)
            {
                return;
            }

            if (direction == LogObject.Direction.InPut) {
                _waitForResponse = true;
                _initialMethodName = methodName;
            }

            connectionString = GetSqlConnectionString();
            callerIpAddress = GetClientIp();
            ipAddress = GetClientIp(HttpContext.Current.Request.UserHostAddress);

            //Log call here

            if (!String.IsNullOrEmpty(_methodName) && xml.IndexOf("<" + _initialMethodName + "Response") > 0)
            {
                //Reset static values to initial
                _methodName = String.Empty;
                _initialMethodName = String.Empty;
                _waitForResponse = false;
            }
        }
        catch (Exception ex)
        {
            //Error handling here
        }
    }
    private static string GetClientIp(string ip = null)
    {
        if (String.IsNullOrEmpty(ip))
        {
            ip = HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
        }
        if (String.IsNullOrEmpty(ip) || ip.Equals("unknown", StringComparison.OrdinalIgnoreCase))
        {
            ip = HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
        }
        if (ip == "::1")
            ip = "127.0.0.1";
        return ip;
    }
}

methodName变量用于确定我们正在等待响应的入站调用.这当然是可选的,但在我的解决方案中,我对其他web服务进行了几次调用,但我想只记录第一次调用的响应.

第二部分是您需要在web.config中添加正确的行.显然,不包括整个类类型定义是敏感的(在这个例子中,只定义了类名,它不起作用.该类从未被初始化.):

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<system.web>
    <webServices>
        <soapExtensionTypes>
            <add group="High" priority="1" type="WsNs.SoapLoggingExtension, WsNs, Version=1.0.0.0, Culture=neutral" />
        </soapExtensionTypes>
    </webServices>
</system.web>
</configuration>