Support IPv6 in async-dns (#25687)

* Support IPv6 in async-dns

* Expect AAAA records for IPv6

akka-actor-tests/src/test/scala/akka/io/dns/internal/AsyncDnsManagerSpec.scala

@@ -4,9 +4,12 @@
 
 package akka.io.dns.internal
 
-import java.net.InetAddress
+import java.net.{ Inet6Address, InetAddress }
 
+import scala.collection.immutable.Seq
 import akka.io.Dns
+import akka.io.dns.{ AAAARecord, ResourceRecord }
+import akka.io.dns.DnsProtocol.{ Resolve, Resolved }
 import akka.testkit.{ AkkaSpec, ImplicitSender }
 
 class AsyncDnsManagerSpec extends AkkaSpec(
@@ -24,6 +27,18 @@ class AsyncDnsManagerSpec extends AkkaSpec(
       val oldProtocolReply = akka.io.Dns.Resolved("127.0.0.1", InetAddress.getByName("127.0.0.1") :: Nil)
       expectMsg(oldProtocolReply)
     }
+
+    "support ipv6" in {
+      dns ! Resolve("::1") // ::1 will short circuit the resolution
+      val Resolved("::1", Seq(AAAARecord("::1", Int.MaxValue, _)), Nil) = expectMsgType[Resolved]
+    }
+
+    "support ipv6 also using the old protocol" in {
+      dns ! akka.io.Dns.Resolve("::1") // ::1 will short circuit the resolution
+      val resolved = expectMsgType[akka.io.Dns.Resolved]
+      resolved.ipv4 should be(Nil)
+      resolved.ipv6.length should be(1)
+    }
   }
 
 }

akka-actor-tests/src/test/scala/akka/io/dns/internal/AsyncDnsResolverSpec.scala

@@ -114,9 +114,7 @@ class AsyncDnsResolverSpec extends AkkaSpec(
       r ! Resolve(name)
       dnsClient1.expectNoMessage(50.millis)
       val answer = expectMsgType[Resolved]
-      answer.records.collect { case r: ARecord ⇒ r }.toSet shouldEqual Set(
+      val Seq(AAAARecord("1:2:3:0:0:0:0:0", Int.MaxValue, _)) = answer.records.collect { case r: AAAARecord ⇒ r }
-        ARecord("1:2:3:0:0:0:0:0", Int.MaxValue, InetAddress.getByName("1:2:3:0:0:0:0:0"))
-      )
     }
 
     "return additional records for SRV requests" in {

akka-actor/src/main/scala/akka/io/dns/internal/AsyncDnsManager.scala

@@ -10,7 +10,7 @@ import java.util.concurrent.TimeUnit
 import akka.actor.{ Actor, ActorLogging, ActorRefFactory, Deploy, Props, Timers }
 import akka.annotation.InternalApi
 import akka.dispatch.{ RequiresMessageQueue, UnboundedMessageQueueSemantics }
-import akka.io.dns.{ ARecord, DnsProtocol, DnsSettings }
+import akka.io.dns.{ AAAARecord, ARecord, DnsProtocol, DnsSettings }
 import akka.io.dns.internal.AsyncDnsManager.CacheCleanup
 import akka.io.{ Dns, DnsExt, PeriodicCacheCleanup }
 import akka.routing.FromConfig
@@ -74,7 +74,10 @@ private[io] final class AsyncDnsManager(val ext: DnsExt) extends Actor
       val adapted = DnsProtocol.Resolve(name)
       val reply = (resolver ? adapted).mapTo[DnsProtocol.Resolved]
         .map { asyncResolved ⇒
-          val ips = asyncResolved.records.collect { case a: ARecord ⇒ a.ip }
+          val ips = asyncResolved.records.collect {
+            case a: ARecord    ⇒ a.ip
+            case a: AAAARecord ⇒ a.ip
+          }
           Dns.Resolved(asyncResolved.name, ips)
         }
       reply pipeTo sender

akka-actor/src/main/scala/akka/io/dns/internal/AsyncDnsResolver.scala

@@ -4,14 +4,14 @@
 
 package akka.io.dns.internal
 
-import java.net.{ InetAddress, InetSocketAddress }
+import java.net.{ Inet4Address, Inet6Address, InetAddress, InetSocketAddress }
 import java.nio.charset.StandardCharsets
 
 import akka.actor.{ Actor, ActorLogging, ActorRef, ActorRefFactory, Props }
 import akka.annotation.InternalApi
 import akka.io.dns.DnsProtocol.{ Ip, RequestType, Srv }
 import akka.io.dns.internal.DnsClient._
-import akka.io.dns.{ ARecord, DnsProtocol, DnsSettings, ResourceRecord }
+import akka.io.dns.{ AAAARecord, ARecord, DnsProtocol, DnsSettings, ResourceRecord }
 import akka.pattern.{ ask, pipe }
 import akka.util.{ Helpers, Timeout }
 
@@ -59,7 +59,10 @@ private[io] final class AsyncDnsResolver(
       Future.fromTry {
         Try {
           val address = InetAddress.getByName(name) // only checks validity, since known to be IP address
-          val record = ARecord(name, Int.MaxValue, address)
+          val record = address match {
+            case _: Inet4Address           ⇒ ARecord(name, Int.MaxValue, address)
+            case ipv6address: Inet6Address ⇒ AAAARecord(name, Int.MaxValue, ipv6address)
+          }
           DnsProtocol.Resolved(name, record :: Nil)
         }
       }