Port akka.io.dns and akka.discovery.dns

[Arkatufus]

Porting akka.discovery.dns over from the JVM implementation would also require a port of the akka.io.dns namespace.
We could not use the built-in DNS client in dotnet because it is seriouly lacking in features, as it only handles the ANAME DNS query, so we would also need to port the JVM DNS client implementation or roll our own DNS client implementation.

• Port DNS client
  • Able to handle DNS protocol, especially the A, AAAA, and SRV records and be able to extract TTL information
  • Have a cache for all resolved DNS record lookup and be able to do periodic check for record expiry
  • Test suite
• akka.discovery.dns.DnsServiceDiscovery
  • Test suite

[ismaelhamed]

@Arkatufus I'd say DnsClient checks all the boxes.

[Aaronontheweb]

I'd be fine taking a dependency on that inside Akka.Discovery. Probably wouldn't want that as part of Akka.IO. Do you think that'd be a reasonable compromise?

[ismaelhamed]

Sounds good. Actually, what would be a use case for Akka.IO.Dns? I don't think I've seen it being used anywhere.

[Aaronontheweb]

Sounds good. Actually, what would be a use case for Akka.IO.Dns? I don't think I've seen it being used anywhere.

Other than Akka.Discovery - I have no idea. Doesn't make a lot of sense to have it IMHO.