如何将Http请求复制到另一个Web服务?

时间:2011-11-30 12:04:36

标签: c# asp.net web-services httpwebrequest web

我目前在同一台PC上安装了两个相同的Web服务用于测试目的。第一个服务接收的请求也会被转到第二个服务。我的意图是使用HttpModule来做到这一点。我在application.BeginRequest期间处理请求。

public void AsyncForwardRequest(HttpRequest request)
{
    try
    {
        // Prepare web request...
        HttpWebRequest req = (HttpWebRequest)WebRequest.Create(WSaddress);

        req.Credentials = CredentialCache.DefaultCredentials;
        req.Headers.Add("SOAPAction", request.Headers["SOAPAction"]);
        req.ContentType = request.Headers["Content-Type"];
        req.Accept = request.Headers["Accept"];
        req.Method = request.HttpMethod;

        // Send the data.
        long posStream = request.InputStream.Position;
        long len = request.InputStream.Length;
        byte[] buff = new byte[len];
        request.InputStream.Seek(0, SeekOrigin.Begin);
        if (len < int.MaxValue && request.InputStream.Read(buff, 0, (int)len) > 0)
        {
            using (Stream stm = req.GetRequestStream())
            {
                stm.Write(buff, 0, (int)len);
            }

            request.InputStream.Position = posStream;
            DebugOutputStream(request.InputStream);
            request.InputStream.Seek(0, SeekOrigin.Begin);

            IAsyncResult result = (IAsyncResult)req.BeginGetResponse(new AsyncCallback(RespCallback), req);
        }
    }
    catch (Exception ex)
    {

        App.Error2(String.Format("RequestDuplicatorModule - BeginRequest; ERROR begin request: {0}", ex.Message), ex);
    }

private static void RespCallback(IAsyncResult asynchronousResult)
{
    try
    {
        // State of request is asynchronous.
        var req = (HttpWebRequest)asynchronousResult.AsyncState;
        WebResponse resp = (HttpWebResponse)req.EndGetResponse(asynchronousResult);

        Stream responseStream = resp.GetResponseStream();
        System.IO.Stream stream = responseStream;
        Byte[] arr = new Byte[1024 * 100];
        stream.Read(arr, 0, 1024 * 100);
        if (arr.Length > 0)
        {
            string body = (new ASCIIEncoding()).GetString(arr);
            Debug.Print(body);
        }
    }
    catch (WebException ex)
    {
        App.Error2(String.Format("RequestDuplicatorModule - BeginRequest; ERROR begin request: {0}", ex.Message), ex);
    }

}

此(HttpWebResponse)req.EndGetResponse(asynchronousResult)抛出异常:500内部服务器错误并失败。原始请求很顺利。

request.InnerStream:     ...

这与Web服务地址有什么不同吗?在我的情况下,他们是: http://localhost/WS/service.asmx HTTP://localhost/WS_replicate/service.asmx

2 个答案:

答案 0 :(得分:1)

我至少会实现这一点,以便能够读取状态为500的httpwebrequest的内容:

catch (WebException ex)
{
    HttpWebResponse webResponse = (HttpWebResponse)ex.Response;
    Stream dataStream = webResponse.GetResponseStream();

    if (dataStream != null)
    {
        StreamReader reader = new StreamReader(dataStream);
        response = reader.ReadToEnd();
    }
}

虽然没有回答你的问题,我建议有一个简单的amsx来读取请求,并将请求发布到两个不同的Web服务。如果您需要一些代码,请告诉我。

其他优点是asmx将更容易支持开发人员以及处理部署的人员。您可以添加配置选项以使实际网址动态化。

答案 1 :(得分:0)

能够修改AsyncForwardRequest方法,以便我可以实际编辑SoapEnvelope本身:

string buffString = System.Text.UTF8Encoding.UTF8.GetString(buff);

using (Stream stm = req.GetRequestStream())
{
    bool stmIsReadable = stm.CanRead;  //false, stream is not readable, how to get
                                       //around this?
                                       //solution: read Byte Array into a String,
                                       //modify <wsa:to>, write String back into a
                                       //Buffer, write Buffer to Stream

    buffString = buffString.Replace("http://localhost/WS/Service.asmx", WSaddress);

    //write modded string to buff
    buff = System.Text.UTF8Encoding.UTF8.GetBytes(buffString);

    stm.Write(buff, 0, (int)buff.Length);
}