private static string CreateDeflateOptionsHeader(WebSocketDeflateOptions options)
{
var builder = new StringBuilder();
builder.Append("permessage-deflate");
if (options.ClientMaxWindowBits != 15)
{
builder.Append("; client_max_window_bits=").Append(options.ClientMaxWindowBits);
}
if (!options.ClientContextTakeover)
{
builder.Append("; client_no_context_takeover");
}
if (options.ServerMaxWindowBits != 15)
{
builder.Append("; server_max_window_bits=").Append(options.ServerMaxWindowBits);
}
if (!options.ServerContextTakeover)
{
builder.Append("; server_no_context_takeover");
}
return(builder.ToString());
}
public async Task PerMessageDeflateHeaders(int clientWindowBits, bool clientContextTakeover,
int serverWindowBits, bool serverContextTakover,
string expected)
{
await LoopbackServer.CreateClientAndServerAsync(async uri =>
{
using var client = new ClientWebSocket();
using var cancellation = new CancellationTokenSource(TimeOutMilliseconds);
client.Options.DangerousDeflateOptions = new WebSocketDeflateOptions
{
ClientMaxWindowBits = clientWindowBits,
ClientContextTakeover = clientContextTakeover,
ServerMaxWindowBits = serverWindowBits,
ServerContextTakeover = serverContextTakover
};
await client.ConnectAsync(uri, cancellation.Token);
object webSocketHandle = client.GetType().GetField("_innerWebSocket", BindingFlags.NonPublic | BindingFlags.Instance).GetValue(client);
WebSocketDeflateOptions negotiatedDeflateOptions = (WebSocketDeflateOptions)webSocketHandle.GetType()
.GetField("_negotiatedDeflateOptions", BindingFlags.NonPublic | BindingFlags.Instance)
.GetValue(webSocketHandle);
Assert.Equal(clientWindowBits - 1, negotiatedDeflateOptions.ClientMaxWindowBits);
Assert.Equal(clientContextTakeover, negotiatedDeflateOptions.ClientContextTakeover);
Assert.Equal(serverWindowBits - 1, negotiatedDeflateOptions.ServerMaxWindowBits);
Assert.Equal(serverContextTakover, negotiatedDeflateOptions.ServerContextTakeover);
}, server => server.AcceptConnectionAsync(async connection =>
{
var extensionsReply = CreateDeflateOptionsHeader(new WebSocketDeflateOptions
{
ClientMaxWindowBits = clientWindowBits - 1,
ClientContextTakeover = clientContextTakeover,
ServerMaxWindowBits = serverWindowBits - 1,
ServerContextTakeover = serverContextTakover
});
Dictionary <string, string> headers = await LoopbackHelper.WebSocketHandshakeAsync(connection, extensionsReply);
Assert.NotNull(headers);
Assert.True(headers.TryGetValue("Sec-WebSocket-Extensions", out string extensions));
Assert.Equal(expected, extensions);
}), new LoopbackServer.Options {
WebSocketEndpoint = true
});
}