使用 HttpWebRequest.GetResponse 时出现 KeepAliveException

Question

我正在尝试使用 HttpWebRequest 将附件发布到 CouchDB。但是，当我尝试“response = (HttpWebResponse)httpWebRequest.GetResponse();”时我收到一个 WebException，其中包含消息“底层连接已关闭：服务器关闭了预期保持活动状态的连接。”

我发现一些文章指出将 keepalive 设置为 false 并将 httpversion 设置为 1.0 可以解决这种情况。我发现它不会产生完全相同的错误，而且我不想采用这种方法，因为由于它处理连接的方式，我不想使用 1.0 版本。

欢迎任何建议或想法。我会尝试所有这些，直到其中一个有效为止！

public ServerResponse PostAttachment(Server server, Database db, Attachment attachment)
    {
        Stream dataStream;
        HttpWebResponse response = null;
        StreamReader sr = null;
        byte[] buffer;
        string json;
        string boundary = "----------------------------" + DateTime.Now.Ticks.ToString("x");
        string headerTemplate = "Content-Disposition: form-data; name=\"_attachments\"; filename=\"" + attachment.Filename + "\"\r\n Content-Type: application/octet-stream\r\n\r\n";
        byte[] headerbytes = System.Text.Encoding.UTF8.GetBytes(headerTemplate);
        byte[] boundarybytes = System.Text.Encoding.ASCII.GetBytes("\r\n--" + boundary + "\r\n");


        HttpWebRequest httpWebRequest = (HttpWebRequest)WebRequest.Create("http://" + server.Host + ":" + 
            server.Port.ToString() + "/" + db.Name + "/" + attachment.Document.Id);
        httpWebRequest.ContentType = "multipart/form-data; boundary=" + boundary;
        httpWebRequest.Method = "POST";
        httpWebRequest.KeepAlive = true;
        httpWebRequest.ContentLength = attachment.Stream.Length + headerbytes.Length + boundarybytes.Length;

        if (!string.IsNullOrEmpty(server.EncodedCredentials))
            httpWebRequest.Headers.Add("Authorization", server.EncodedCredentials);

        if (!attachment.Stream.CanRead)
            throw new System.NotSupportedException("The stream cannot be read.");

        // Get the request stream
        try
        {
            dataStream = httpWebRequest.GetRequestStream();
        }
        catch (Exception e)
        {
            throw new WebException("Failed to get the request stream.", e);
        }


        buffer = new byte[server.BufferSize];
        int bytesRead;

        dataStream.Write(headerbytes,0,headerbytes.Length); 

        attachment.Stream.Position = 0;
        while ((bytesRead = attachment.Stream.Read(buffer, 0, buffer.Length)) > 0)
        {
            dataStream.Write(buffer, 0, bytesRead);
        }

        dataStream.Write(boundarybytes, 0, boundarybytes.Length);
        dataStream.Close();

        // send the request and get the response
        try
        {
            response = (HttpWebResponse)httpWebRequest.GetResponse();
        }
        catch (Exception e)
        {
            throw new WebException("Invalid response received from server.", e);
        }

        // get the server's response json
        try
        {
            dataStream = response.GetResponseStream();
            sr = new StreamReader(dataStream);
            json = sr.ReadToEnd();
        }
        catch (Exception e)
        {
            throw new WebException("Failed to access the response stream.", e);
        }

        // close up all our streams and response
        sr.Close();
        dataStream.Close();
        response.Close();

        // Deserialize the server response
        return ConvertTo.JsonToServerResponse(json);
    }

Answer 1

经过对该主题的大量研究后，我决定使用 PUT。虽然 Futon 使用 POST 方法，但它没有记录。对于将来阅读本文的任何人，请使用 PUT 方法，它会让您的生活变得更加轻松。