/// <summary>
/// Sends an HTTP request and return an HTTP response as asynchronous operation.
/// </summary>
/// <param name="content"></param>
/// <param name="requestCancellationToken"></param>
/// <returns></returns>
public async Task<HttpResponse> SendAsync(HttpContent content, CancellationToken requestCancellationToken)
{
this.CheckProtocol(content != null);
if (this.SetRequestSubmitted())
{
throw new InvalidOperationException("This HTTP request has been submitted.");
}
var linkedCts = CancellationTokenSource.CreateLinkedTokenSource(requestCancellationToken);
if (this.SetTimeout(linkedCts))
{
_requestCancellationToken = linkedCts.Token;
}
_submitContent = content;
var connection = this.ServicePoint.SubmitRequest(this);
var responseData = await this.SendRequestAsync(connection).ConfigureAwait(false);
return new HttpResponse(_uri, _method, responseData, _automaticDecompression);
}
private async Task WriteRequestAsync(Connection connection)
{
this.UpdateHeaders();
if (_httpWriteMode != HttpWriteMode.None)
{
if (_httpWriteMode == HttpWriteMode.Chunked)
{
_headers.AddInternal(HttpHeaderNames.TransferEncoding, ChunkedHeader);
}
else
{
if (_contentLength >= 0L)
{
_headers.SetInternal(HttpHeaderNames.ContentLength, _contentLength.ToString());
}
}
//100-continue ??
}
//Accept-Encoding header
var acceptEncodingValues = this.Accept ?? string.Empty;
if ((_automaticDecompression & DecompressionMethods.GZip) != DecompressionMethods.None && acceptEncodingValues.IndexOf(GZipHeader, StringComparison.OrdinalIgnoreCase) < 0)
{
if ((_automaticDecompression & DecompressionMethods.Deflate) != 0
&& acceptEncodingValues.IndexOf(DeflateHeader, StringComparison.OrdinalIgnoreCase) < 0)
{
_headers.AddInternal(HttpHeaderNames.AcceptEncoding, GZipHeader + ", " + DeflateHeader);
}
else
{
_headers.AddInternal(HttpHeaderNames.AcceptEncoding, GZipHeader);
}
}
else
{
if ((_automaticDecompression & DecompressionMethods.Deflate) != DecompressionMethods.None && acceptEncodingValues.IndexOf("deflate", StringComparison.OrdinalIgnoreCase) < 0)
{
_headers.AddInternal(HttpHeaderNames.AcceptEncoding, DeflateHeader);
}
}
if (_keepAlive)
{
_headers.SetInternal(HttpHeaderNames.Connection, "Keep-Alive");
}
else
{
_headers.SetInternal(HttpHeaderNames.Connection, "Close");
}
var requestHeadersString = _headers.ToString();
string requestLine = null;
if (this.UsesProxySemantics)
{
requestLine = this.GenerateProxyRequestLine();
}
else
{
requestLine = this.GenerateRequestLine();
}
// Request-Line = Method SP Request-URI SP HTTP-Version CRLF
// i.e. GET http://www.w3.org/pub/WWW/TheProject.html HTTP/1.1\r\n
var writeBytesCount = requestHeadersString.Length + requestLine.Length + RequestLineConstantSize;
byte[] writeBuffer = null;
var usePooledBuffer = false;
var offset = 0;
if (connection.Buffer.Length >= writeBytesCount)
{
writeBuffer = connection.Buffer.Array;
offset = connection.Buffer.Offset;
usePooledBuffer = true;
}
else
{
writeBuffer = new byte[writeBytesCount];
}
offset += Encoding.ASCII.GetBytes(requestLine, 0, requestLine.Length, writeBuffer, offset);
Buffer.BlockCopy(HttpBytes, 0, writeBuffer, offset, HttpBytes.Length);
offset += HttpBytes.Length;
writeBuffer[offset++] = (byte)(_version == HttpVersion.HTTP20 ? '2' : '1');
writeBuffer[offset++] = (byte)'.';
writeBuffer[offset++] = (byte)(_version == HttpVersion.HTTP20 ? '0' : '1');
writeBuffer[offset++] = (byte)'\r';
writeBuffer[offset++] = (byte)'\n';
Encoding.UTF8.GetBytes(requestHeadersString, 0, requestHeadersString.Length, writeBuffer, offset);
offset += requestHeadersString.Length;
//transfer data
var beginReadIndex = 0;
var leftWriteBytes = writeBytesCount;
while (leftWriteBytes > 0)
{
var count = Math.Min(writeBytesCount - beginReadIndex, connection.Buffer.Length);
if (!usePooledBuffer)
{
Buffer.BlockCopy(writeBuffer, beginReadIndex, connection.Buffer.Array, connection.Buffer.Offset, count);
}
var writeBytes = await connection.WritePooledBufferAsync(connection.Buffer.Offset + beginReadIndex, count);
leftWriteBytes -= writeBytes;
beginReadIndex += writeBytes;
}
if (_method.AllowRequestContent && _submitContent != null)
{
using (_submitContent)
{
await _submitContent.CopyToAsync(new ConnectStream(connection, this));
_submitContent = null;
}
}
}