node: Add driver dsl test, expose some needed functions

node/src/main/kotlin/com/r3corda/node/driver/Driver.kt

@@ -68,6 +68,7 @@ private fun getTimestampAsDirectoryName(): String {
 
 class DriverHandle(private val driverDsl: DriverDSL, private val shutdownHook: Thread) {
     val messagingService = driverDsl.messagingService
+    val networkMapCache = driverDsl.networkMapCache
 
     fun waitForAllNodesToFinish() {
         driverDsl.waitForAllNodesToFinish()
@@ -79,7 +80,7 @@ class DriverHandle(private val driverDsl: DriverDSL, private val shutdownHook: T
     }
 }
 
-private fun <A> poll(f: () -> A?): A {
+fun <A> poll(f: () -> A?): A {
     var counter = 0
     var result = f()
     while (result == null && counter < 30) {

node/src/test/kotlin/com/r3corda/node/driver/DriverTests.kt

@@ -0,0 +1,48 @@
+package com.r3corda.node.driver
+
+import com.r3corda.node.services.messaging.ArtemisMessagingService
+import com.r3corda.node.services.transactions.NotaryService
+import org.junit.Test
+import java.net.Socket
+import java.net.SocketException
+
+
+class DriverTests {
+
+    @Test
+    fun simpleNodeStartupShutdownWorks() {
+
+        // Start a notary
+        val (handle, notaryNodeInfo) = driver(quasarPath = "../lib/quasar.jar") {
+            startNode(setOf(NotaryService.Type), "TestNotary")
+        }
+        // Check that the node is registered in the network map
+        poll {
+            handle.networkMapCache.get(NotaryService.Type).firstOrNull {
+                it.identity.name == "TestNotary"
+            }
+        }
+        // Check that the port is bound
+        val address = notaryNodeInfo.address as ArtemisMessagingService.Address
+        poll {
+            try {
+                Socket(address.hostAndPort.hostText, address.hostAndPort.port).close()
+                Unit
+            } catch (_exception: SocketException) {
+                null
+            }
+        }
+
+        // Shutdown
+        handle.shutdown()
+        // Check that the port is not bound
+        poll {
+            try {
+                Socket(address.hostAndPort.hostText, address.hostAndPort.port).close()
+                null
+            } catch (_exception: SocketException) {
+                Unit
+            }
+        }
+    }
+}