Why does my Alpakka SFTP connector never connect? - scala

Question

I'm new to Alpakka/Akka Streams and I'm trying to set up a stream where I stream data between two SFTP servers with my system in the middle, here's the code.
import akka.actor.ActorSystem
import akka.stream.ActorMaterializer
import akka.stream.alpakka.ftp.scaladsl.Sftp
import akka.stream.alpakka.ftp.{FtpCredentials, SftpSettings}
import akka.stream.scaladsl.Keep
import net.schmizz.sshj.{DefaultConfig, SSHClient}
import java.net.InetAddress
class StreamingSftpTransport {
implicit val system: ActorSystem = ActorSystem("dr-service")
implicit val materializer: ActorMaterializer = ActorMaterializer()
private val PORT = 22
private val USER = "testsftp"
private val CREDENTIALS = FtpCredentials.create(USER, "t3st123")
private val BASEPATH = s"/home/$USER"
private val FILE_NAME = "testfile"
// Set up the source system connection
private val SOURCE_HOSTNAME = "host1"
private val sourceSettings = SftpSettings.apply(host = InetAddress.getByName(SOURCE_HOSTNAME))
.withCredentials(CREDENTIALS)
.withPort(22)
private val sourceClient = new SSHClient(new DefaultConfig)
private val configuredSourceClient = Sftp(sourceClient)
// Set up the destination system connection
private val DEST_HOSTNAME = "host2"
private val destSettings = SftpSettings.apply(host = InetAddress.getByName(DEST_HOSTNAME))
.withCredentials(CREDENTIALS)
.withPort(22)
private val destClient = new SSHClient(new DefaultConfig)
private val configuredDestClient = Sftp(destClient)
/**
* Execute the stream from host1 to host2
*/
def doTransfer(): Unit = {
val source = configuredSourceClient.fromPath(s"$BASEPATH/$FILE_NAME", sourceSettings)
val sink = configuredDestClient.toPath(s"$BASEPATH/$FILE_NAME", destSettings)
val runnable = source.toMat(sink)(Keep.right).run()
}
}
I've called this from a unit test with new StreamingSftpTransport.doTransfer() but it never attempts to connect. What am I doing wrong?

Answer 1

As suggested by artur in the comment on my question, I wasn't blocking on the future so the JVM was exiting before the connection could be established.
Adding the following line allowed the connections to be established
Await.result(runnable, 180 seconds)
PS: Don't do this in production :)