我一直在使用.NET 4.5中的HttpClient掙扎了一段時間。在通過分塊傳輸對WebApi端點(diǎn)進(jìn)行大型流式上傳時，如果服務(wù)器已通過非成功狀態(tài)代碼(未找到，認(rèn)證，授權(quán)，驗(yàn)證錯誤等)響應(yīng)中間請求，則無法停止。HttpClient在收到服務(wù)器響應(yīng)后無法停止流式傳輸

使用ConnectStream類中的調(diào)試器查看它知道它從服務(wù)器收到了一個不成功的狀態(tài)。從服務(wù)器接收到的HTTP狀態(tài)和數(shù)據(jù)將被存儲以備后用，并且從那時起它只是假裝從流中讀取直到結(jié)束。從那時起，線路上沒有任何信息被寫入，并且后來通過HttpResponseMessage提供了響應(yīng)。這種無法解釋的行為給我造成了巨大的問題，因?yàn)樗婕暗牧骺赡芊浅４蟆；ㄙM(fèi)無用的時間讀取流直到結(jié)束，并向用戶顯示不正確的上載報(bào)告。我停止了Web服務(wù)器，遠(yuǎn)程機(jī)器，甚至禁用了本地網(wǎng)絡(luò)接口。 HttpClient不在乎。它不斷從提供的流中讀取數(shù)據(jù)。

我試過HttpCompletionOption.ResponseHeadersRead和StreamedContent或PushStreamContent。同樣的行為。我也嘗試過使用HttpWebRequest，但是它不允許在輸出流上寫入并同時讀取傳入流。有什么辦法阻止客戶端在收到服務(wù)器響應(yīng)后發(fā)送或假裝發(fā)送流？為什么HttpClient的行為如此？

var httpClientHandler = new WebRequestHandler

{

AllowAutoRedirect = true,

PreAuthenticate = false,

CookieContainer = cookieContainer,

UseCookies = true,

CachePolicy = new RequestCachePolicy(RequestCacheLevel.NoCacheNoStore),

AutomaticDecompression = DecompressionMethods.Deflate | DecompressionMethods.GZip

};

var httpClient = new HttpClient(_httpClientHandler)

{

BaseAddress = baseApiUrl,

Timeout = Timeout.InfiniteTimeSpan;

};

httpClient.DefaultRequestHeaders.TransferEncodingChunked = true;

httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("text/plain", 0.8));

httpClient.DefaultRequestHeaders.AcceptCharset.Add(new StringWithQualityHeaderValue("UTF-8"));

httpClient.DefaultRequestHeaders.UserAgent.Add(new ProductInfoHeaderValue(appName, appVersion));

var requestContent = new StringContent(serializedRequest, Encoding.UTF8, "application/json");

// the monitored stream is an implementation of the stream that proxies the calls to a classic file stream

// here I monitor the calls made to Read(byte[] buffer, int offset, int count) method

// tried with both CanSeek = false or true - the HttpClient reads the whole stream no matter what.

var streamedContent = new StreamContent(monitoredStream);

streamedContent.Headers.ContentDisposition = new ContentDispositionHeaderValue("form-data")

{

FileName = "upload.bin",

Size = monitoredStream.Length

};

var httpRequestMessage = new HttpRequestMessage(HttpMethod.Post, relativeUrl)

{

Content = new MultipartFormDataContent

{

requestContent,

streamedContent

}

};

// the Owin middleware could fail checking authentication, an authorization error could occur,

// or the WebApi controller could receive the first part of the multipart data and reject the request

// from the moment data was received from the server, mid-stream, I could safely unplug the network cable

// socket erros are being ignored, actually the underlying socket is no longer used

// the response message contains the status code and data received during the transmission of the request at the end of this call

var httpResponseMessage = await _httpClient.SendAsync(httpRequestMessage, HttpCompletionOption.ResponseHeadersRead, cancellationToken);

2015-12-16

MoonStom

+0

你能顯示你的代碼嗎？ –

總結(jié)

以上是生活随笔為你收集整理的服务器流式响应,HttpClient在收到服务器响应后无法停止流式传输的全部內(nèi)容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網(wǎng)站內(nèi)容還不錯，歡迎將生活随笔推薦給好友。