#3649 - Add ZStream.fromTcpSocketServer

[regis-leray]

closes #3649

[iravid]

@regis-leray Nice work. This is looking good.

Can we switch to using AsynchronousServerSocketChannel here? See https://stackoverflow.com/questions/22177722/java-nio-non-blocking-channels-vs-asynchronouschannels for reasoning.

[regis-leray]

@iravid thanks for the the tips asynchronous, i tested locally it works. missing test and it will be ready to merge

[iravid]

Thank you, this looks great.

Left a few more requests. Tests can go in ZStreamPlatformSpecificSpec.scala.

[iravid]

Left a few minor suggestions while this is still open.

[mschuwalow]

What do you think about using ZManaged#scope to pull the manageds into the stream itself?
This leads to a far more ergonomic signature and is still resource safe as all connections will be closed when the stream is closed.

Something like this https://github.com/zio/zio-keeper/blob/master/keeper/src/main/scala/zio/keeper/transport/tcp.scala

[iravid]

Yes I think that'd be good. ZStream[Connection] is indeed nicer than ZStream[Managed[Connection]]. What do you think @regis-leray?

[regis-leray]

👍

[iravid]

We just need a test or two after this @regis-leray and this should be good to go.

[regis-leray]

@iravid sorry for the delay. I provided some test.

[regis-leray]

@iravid i added some javadoc

[iravid]

One last tweak then good to merge. Thanks @regis-leray

[iravid]

This is subtly wrong, because it means that as soon as you progress to the next connection, the previous connection is closed. Instead, let's use ZManaged.scope here:

for {
  server <- ZStream.managed(...)
  registerConnection <- ZStream.managed(ZManaged.scope)
  conn <- ZStream.repeatEffect {
                 IO.effectAsync(...).flatMap(managedConn => registerConnection(managedConn).map(_._2))
                }
} yield conn

[regis-leray]

Thanks for the tip ! i was not aware of this ZManaged.scope

[iravid]

Great work @regis-leray, thank you!