Runtime: Add implementation for SetTcpKeepAlive in ServicePoint

[ashishnegi]

Hi

I am porting my .NetFramework project to .NetStd 2.0.

I have long running workloads. I need to set Tcp Keep-Alive messages. This is supported in .NetFramework.
Its implementation in corefx is not doing anything after validation.
https://github.com/dotnet/corefx/blob/master/src/System.Net.ServicePoint/src/System/Net/ServicePoint.cs#L101

Hence, my HttpClient Api calls don't send tcp keep alive messages.

Is there any workaround ?
When can we expect full implementation of SetTcpKeepAlive ?

[jahmai]

It's 2019 now. Any updated plans for this? Any alternative?

[karelz]

It's in Future milestone. The top post does not have any upvotes (please add yours if you need it).
Overall, not enough to fund it anytime soon - we have higher-impact problems to solve in networking area.

[ashishnegi]

ping. @karelz
Is there any workaround/alternative ? any other library ? anything ?

[karelz]

It is now exposed on Sockets - see dotnet/runtime#24041
We do not have it exposed on Http stack yet AFAIK. The priority is low given the small demand.

[ashishnegi]

My use case : Azure Load Balancer terminates the http requests that are longer than 4 minutes if httpclient does not send TCP-keep alive packets.

[stephentoub]

We do not have it exposed on Http stack yet AFAIK. The priority is low given the small demand.

FWIW, my preference would be to expose this capability via something like https://github.com/dotnet/corefx/issues/23426#issuecomment-421627596, i.e. add a callback to SocketsHttpHandler that either provides the created Socket to a callback or invokes a method to create the Socket, such that a callback can manipulate the Socket however it likes, including calling the APIs @karelz mentions to configure keepalive.

[karelz]

Triage: We think there is another dupe of this - more general as @stephentoub describes above.

[TalAloni]

If you need it now - I did a backport of SocketsHttpHandler to .NET Standard 2.0 and added a SocketCreated event that allows you to configure TCP Keepalive on the socket, it's on NuGet / GitHub.

I also ported the Microsoft tests for your peace of mind.