protected override void Encode(IChannelHandlerContext context, object message, List <object> output)
{
IByteBuffer buf = null;
if (message is IHttpMessage)
{
if (this.state != StInit)
{
ThrowHelper.ThrowInvalidOperationException_UnexpectedMsg(message, this.state);
}
var m = (T)message;
buf = context.Allocator.Buffer((int)this.headersEncodedSizeAccumulator);
// Encode the message.
this.EncodeInitialLine(buf, m);
this.state = this.IsContentAlwaysEmpty(m) ? StContentAlwaysEmpty
: HttpUtil.IsTransferEncodingChunked(m) ? StContentChunk : StContentNonChunk;
this.SanitizeHeadersBeforeEncode(m, this.state == StContentAlwaysEmpty);
this.EncodeHeaders(m.Headers, buf);
_ = buf.WriteShort(HttpConstants.CrlfShort);
this.headersEncodedSizeAccumulator = HeadersWeightNew * PadSizeForAccumulation(buf.ReadableBytes)
+ HeadersWeightHistorical * this.headersEncodedSizeAccumulator;
}
// Bypass the encoder in case of an empty buffer, so that the following idiom works:
//
// ch.write(Unpooled.EMPTY_BUFFER).addListener(ChannelFutureListener.CLOSE);
//
// See https://github.com/netty/netty/issues/2983 for more information.
if (message is IByteBuffer potentialEmptyBuf)
{
if (!potentialEmptyBuf.IsReadable())
{
output.Add(potentialEmptyBuf.Retain());
return;
}
}
switch (message)
{
case IHttpContent _:
case IByteBuffer _:
case IFileRegion _:
switch (this.state)
{
case StInit:
ThrowHelper.ThrowInvalidOperationException_UnexpectedMsg(message); break;
case StContentNonChunk:
long contentLength = ContentLength(message);
if (contentLength > 0)
{
if (buf is object && buf.WritableBytes >= contentLength && message is IHttpContent)
{
// merge into other buffer for performance reasons
_ = buf.WriteBytes(((IHttpContent)message).Content);
output.Add(buf);
}
else
{
if (buf is object)
{
output.Add(buf);
}
output.Add(EncodeAndRetain(message));
}
if (message is ILastHttpContent)
{
this.state = StInit;
}
break;
}
goto case StContentAlwaysEmpty; // fall-through!
case StContentAlwaysEmpty:
// ReSharper disable once ConvertIfStatementToNullCoalescingExpression
if (buf is object)
{
// We allocated a buffer so add it now.
output.Add(buf);
}
else
{
// Need to produce some output otherwise an
// IllegalStateException will be thrown as we did not write anything
// Its ok to just write an EMPTY_BUFFER as if there are reference count issues these will be
// propagated as the caller of the encode(...) method will release the original
// buffer.
// Writing an empty buffer will not actually write anything on the wire, so if there is a user
// error with msg it will not be visible externally
output.Add(Unpooled.Empty);
}
break;
case StContentChunk:
if (buf is object)
{
// We allocated a buffer so add it now.
output.Add(buf);
}
this.EncodeChunkedContent(context, message, ContentLength(message), output);
break;
default:
ThrowHelper.ThrowEncoderException_UnexpectedState(this.state, message); break;
}
if (message is ILastHttpContent)
{
this.state = StInit;
}
break;
default:
output.Add(buf);
break;
}
}