StreamSocketOutput.WriteAsync is Sync (SSL)

[benaadams]

This is used for wrapped streams such as Ssl. There is currently an issue with it being async; so it is currently implemented as sync.

public Task WriteAsync(ArraySegment<byte> buffer, bool immediate, bool chunk, CancellationToken cancellationToken)
{
    // TODO: Use _outputStream.WriteAsync
    Write(buffer, immediate, chunk);
    return TaskUtilities.CompletedTask;
}

Tests do catch the issue current; e.g. switching to async causes the following failures:

Microsoft.AspNet.Server.KestrelTests.HttpsConnectionFilterTests.CanReadAndWriteWithHttpsConnectionFilter [FAIL]
Microsoft.AspNet.Server.KestrelTests.HttpsConnectionFilterTests.HttpsSchemePassedToRequestFeature [FAIL]
Microsoft.AspNet.Server.KestrelTests.HttpsConnectionFilterTests.AllowCertificateContinuesWhenNoCertificate [FAIL]

Blockers

• Two Stream.Read/WriteAsync improvements dotnet/corefx#5534
• Several Stream.Read/WriteAsync improvements dotnet/coreclr#2724
• Porting async implementation and adding TPL overrides for SslStream Read/WriteAsync dotnet/corefx#5541
• Replace StreamAsyncHelper with StreamApmExtensions in System.Net.Security dotnet/corefx#7800
• Port to RC2: Replace StreamAsyncHelper with StreamApmExtensions in System.Net.Security dotnet/corefx#7819

[muratg]

@benaadams Does this happen only with connection filters?

Backlogging this for now.

[benaadams]

Yes, so https/Ssl

[benaadams]

Looks like there is a bad interaction with Stream's default implementation of BeginRead/EndRead which calls through to the synchronous LibuvStream.Read then it all goes wrong.

Not particularly sure why they are getting called though.

[benaadams]

I think it might be SslStream causing this

Looks like it goes something like this: Async->Sync->Async->Wait()

[benaadams]

Added https://github.com/dotnet/corefx/issues/5488 is a corefx issue

[benaadams]

@muratg this may now be unblocked depending on outcome of dotnet/corefx#7819 (comment)

Have rebased the fix