Merge pull request #333 from jboner/wip-1841-selectable-local-nic-√

Adding support for specifying localAddress in remote config

akka-remote/src/main/resources/reference.conf

@@ -100,6 +100,10 @@ akka {
       # Default is 2552 (AKKA), use 0 if you want a random available port
       port = 2552
 
+      # (O) The address of a local network interface (IP Address) to bind to when creating
+      # outbound connections. Set to "" or "auto" for automatic selection of local address.
+      outbound-local-address = "auto"
+
       # (I&O) Increase this if you want to be able to send messages with large payloads
       message-frame-size = 1 MiB
 

akka-remote/src/main/scala/akka/remote/netty/Client.scala

@@ -157,12 +157,12 @@ class ActiveRemoteClient private[akka] (
       openChannels = new DefaultDisposableChannelGroup(classOf[RemoteClient].getName)
 
       executionHandler = new ExecutionHandler(netty.executor)
-
       val b = new ClientBootstrap(netty.clientChannelFactory)
       b.setPipelineFactory(new ActiveRemoteClientPipelineFactory(name, b, executionHandler, remoteAddress, localAddress, this))
       b.setOption("tcpNoDelay", true)
       b.setOption("keepAlive", true)
       b.setOption("connectTimeoutMillis", settings.ConnectionTimeout.toMillis)
+      settings.OutboundLocalAddress.foreach(s ⇒ b.setOption("localAddress", new InetSocketAddress(s, 0)))
       bootstrap = b
 
       val remoteIP = InetAddress.getByName(remoteAddress.host.get)

akka-remote/src/main/scala/akka/remote/netty/Settings.scala

@@ -40,6 +40,11 @@ class NettySettings(config: Config, val systemName: String) {
     case value ⇒ value
   }
 
+  val OutboundLocalAddress: Option[String] = getString("outbound-local-address") match {
+    case "auto" | "" | null ⇒ None
+    case some               ⇒ Some(some)
+  }
+
   @deprecated("WARNING: This should only be used by professionals.", "2.0")
   val PortSelector = getInt("port")
 

akka-remote/src/test/scala/akka/remote/RemoteConfigSpec.scala

@@ -43,6 +43,7 @@ class RemoteConfigSpec extends AkkaSpec(
       UsePassiveConnections must be(true)
       Hostname must not be "" // will be set to the local IP
       PortSelector must be(0)
+      OutboundLocalAddress must be(None)
       MessageFrameSize must be(1048576)
       ConnectionTimeout must be(2 minutes)
       Backlog must be(4096)