public static MessageBody For(
HttpVersion httpVersion,
FrameRequestHeaders headers,
Frame context)
{
// see also http://tools.ietf.org/html/rfc2616#section-4.4
var keepAlive = httpVersion != HttpVersion.Http10;
var connection = headers.HeaderConnection;
var upgrade = false;
if (connection.Count > 0)
{
var connectionOptions = FrameHeaders.ParseConnection(connection);
upgrade = (connectionOptions & ConnectionOptions.Upgrade) == ConnectionOptions.Upgrade;
keepAlive = (connectionOptions & ConnectionOptions.KeepAlive) == ConnectionOptions.KeepAlive;
}
var transferEncoding = headers.HeaderTransferEncoding;
if (transferEncoding.Count > 0)
{
var transferCoding = FrameHeaders.GetFinalTransferCoding(headers.HeaderTransferEncoding);
// https://tools.ietf.org/html/rfc7230#section-3.3.3
// If a Transfer-Encoding header field
// is present in a request and the chunked transfer coding is not
// the final encoding, the message body length cannot be determined
// reliably; the server MUST respond with the 400 (Bad Request)
// status code and then close the connection.
if (transferCoding != TransferCoding.Chunked)
{
context.ThrowRequestRejected(RequestRejectionReason.FinalTransferCodingNotChunked, transferEncoding.ToString());
}
if (upgrade)
{
context.ThrowRequestRejected(RequestRejectionReason.UpgradeRequestCannotHavePayload);
}
return(new ForChunkedEncoding(keepAlive, context));
}
if (headers.ContentLength.HasValue)
{
var contentLength = headers.ContentLength.Value;
if (contentLength == 0)
{
return(keepAlive ? _zeroContentLengthKeepAlive : _zeroContentLengthClose);
}
else if (upgrade)
{
context.ThrowRequestRejected(RequestRejectionReason.UpgradeRequestCannotHavePayload);
}
return(new ForContentLength(keepAlive, contentLength, context));
}
// Avoid slowing down most common case
if (!object.ReferenceEquals(context.Method, HttpMethods.Get))
{
// If we got here, request contains no Content-Length or Transfer-Encoding header.
// Reject with 411 Length Required.
if (HttpMethods.IsPost(context.Method) || HttpMethods.IsPut(context.Method))
{
var requestRejectionReason = httpVersion == HttpVersion.Http11 ? RequestRejectionReason.LengthRequired : RequestRejectionReason.LengthRequiredHttp10;
context.ThrowRequestRejected(requestRejectionReason, context.Method);
}
}
if (upgrade)
{
return(new ForUpgrade(context));
}
return(keepAlive ? _zeroContentLengthKeepAlive : _zeroContentLengthClose);
}