public override void ChannelRead(IChannelHandlerContext ctx, object msg)
{
if (msg is IHttpResponse response &&
WebSocketExtensionUtil.IsWebsocketUpgrade(response.Headers))
{
string extensionsHeader = null;
if (response.Headers.TryGet(HttpHeaderNames.SecWebsocketExtensions, out ICharSequence value))
{
extensionsHeader = value.ToString();
}
var pipeline = ctx.Pipeline;
if (extensionsHeader is object)
{
List <WebSocketExtensionData> extensions =
WebSocketExtensionUtil.ExtractExtensions(extensionsHeader);
var validExtensions = new List <IWebSocketClientExtension>(extensions.Count);
int rsv = 0;
foreach (WebSocketExtensionData extensionData in extensions)
{
IWebSocketClientExtension validExtension = null;
foreach (IWebSocketClientExtensionHandshaker extensionHandshaker in this.extensionHandshakers)
{
validExtension = extensionHandshaker.HandshakeExtension(extensionData);
if (validExtension is object)
{
break;
}
}
if (validExtension is object && 0u >= (uint)(validExtension.Rsv & rsv))
{
rsv = rsv | validExtension.Rsv;
validExtensions.Add(validExtension);
}
else
{
ThrowHelper.ThrowCodecException_InvalidWSExHandshake(extensionsHeader);
}
}
foreach (IWebSocketClientExtension validExtension in validExtensions)
{
WebSocketExtensionDecoder decoder = validExtension.NewExtensionDecoder();
WebSocketExtensionEncoder encoder = validExtension.NewExtensionEncoder();
_ = pipeline.AddAfter(ctx.Name, decoder.GetType().Name, decoder);
_ = pipeline.AddAfter(ctx.Name, encoder.GetType().Name, encoder);
}
}
_ = pipeline.Remove(ctx.Name);
}
base.ChannelRead(ctx, msg);
}
public override Task WriteAsync(IChannelHandlerContext ctx, object msg)
{
Action <Task> continuationAction = null;
if (msg is IHttpResponse response &&
WebSocketExtensionUtil.IsWebsocketUpgrade(response.Headers) &&
this.validExtensions != null)
{
string headerValue = null;
if (response.Headers.TryGet(HttpHeaderNames.SecWebsocketExtensions, out ICharSequence value))
{
headerValue = value?.ToString();
}
foreach (IWebSocketServerExtension extension in this.validExtensions)
{
WebSocketExtensionData extensionData = extension.NewReponseData();
headerValue = WebSocketExtensionUtil.AppendExtension(headerValue,
extensionData.Name, extensionData.Parameters);
}
continuationAction = promise =>
{
if (promise.Status == TaskStatus.RanToCompletion)
{
foreach (IWebSocketServerExtension extension in this.validExtensions)
{
WebSocketExtensionDecoder decoder = extension.NewExtensionDecoder();
WebSocketExtensionEncoder encoder = extension.NewExtensionEncoder();
ctx.Channel.Pipeline.AddAfter(ctx.Name, decoder.GetType().Name, decoder);
ctx.Channel.Pipeline.AddAfter(ctx.Name, encoder.GetType().Name, encoder);
}
}
ctx.Channel.Pipeline.Remove(ctx.Name);
};
if (headerValue != null)
{
response.Headers.Set(HttpHeaderNames.SecWebsocketExtensions, headerValue);
}
}
return(continuationAction == null
? base.WriteAsync(ctx, msg)
: base.WriteAsync(ctx, msg)
.ContinueWith(continuationAction, TaskContinuationOptions.ExecuteSynchronously));
}
private static void SwitchWebSocketExtensionHandler(Task promise, object state)
{
var wrapped = (Tuple <IChannelHandlerContext, List <IWebSocketServerExtension> >)state;
var ctx = wrapped.Item1;
var validExtensions = wrapped.Item2;
var pipeline = ctx.Pipeline;
if (promise.IsSuccess())
{
for (int i = 0; i < validExtensions.Count; i++)
{
IWebSocketServerExtension extension = validExtensions[i];
WebSocketExtensionDecoder decoder = extension.NewExtensionDecoder();
WebSocketExtensionEncoder encoder = extension.NewExtensionEncoder();
_ = pipeline
.AddAfter(ctx.Name, decoder.GetType().Name, decoder)
.AddAfter(ctx.Name, encoder.GetType().Name, encoder);
}
}
}
