Disable the DemoBench tab if the node exits abnormally. (#692)

* Log a message when the CRaSH shell exits.
* Disable the DemoBench tab if the node exits abnormally.

node/src/main/kotlin/net/corda/node/shell/InteractiveShell.kt

@@ -15,6 +15,7 @@ import net.corda.core.flows.FlowLogic
 import net.corda.core.flows.FlowStateMachine
 import net.corda.core.messaging.CordaRPCOps
 import net.corda.core.utilities.Emoji
+import net.corda.core.utilities.loggerFor
 import net.corda.jackson.JacksonSupport
 import net.corda.jackson.StringToMethodCallParser
 import net.corda.node.internal.Node
@@ -70,6 +71,7 @@ import kotlin.concurrent.thread
 // TODO: Make it notice new shell commands added after the node started.
 
 object InteractiveShell {
+    private val log = loggerFor<InteractiveShell>()
     private lateinit var node: Node
 
     /**
@@ -129,6 +131,7 @@ object InteractiveShell {
         thread(name = "Command line shell terminator", isDaemon = true) {
             // Wait for the shell to finish.
             jlineProcessor.closed()
+            log.info("Command shell has exited")
             terminal.restore()
             node.stop()
         }

tools/demobench/src/main/kotlin/net/corda/demobench/rpc/NodeRPC.kt

@@ -17,8 +17,8 @@ class NodeRPC(config: NodeConfig, start: (NodeConfig, CordaRPCOps) -> Unit, invo
     }
 
     private val rpcClient = CordaRPCClient(HostAndPort.fromParts("localhost", config.rpcPort))
+    private var rpcConnection: CordaRPCConnection? = null
     private val timer = Timer()
-    private val connections = Collections.synchronizedCollection(ArrayList<CordaRPCConnection>())
 
     init {
         val setupTask = object : TimerTask() {
@@ -26,7 +26,7 @@ class NodeRPC(config: NodeConfig, start: (NodeConfig, CordaRPCOps) -> Unit, invo
                 try {
                     val user = config.users.elementAt(0)
                     val connection = rpcClient.start(user.username, user.password)
-                    connections.add(connection)
+                    rpcConnection = connection
                     val ops = connection.proxy
 
                     // Cancel the "setup" task now that we've created the RPC client.
@@ -53,7 +53,11 @@ class NodeRPC(config: NodeConfig, start: (NodeConfig, CordaRPCOps) -> Unit, invo
 
     override fun close() {
         timer.cancel()
-        connections.forEach(CordaRPCConnection::close)
+        try {
+            rpcConnection?.close()
+        } catch (e: Exception) {
+            log.error("Failed to close RPC connection (Error: {})", e.message)
+        }
     }
 
 }

tools/demobench/src/main/kotlin/net/corda/demobench/views/NodeTabView.kt

@@ -270,8 +270,13 @@ class NodeTabView : Fragment() {
         nodeTab.text = config.legalName.commonName
         nodeTerminalView.open(config) { exitCode ->
             Platform.runLater {
-                if (exitCode == 0)
+                if (exitCode == 0) {
                     nodeTab.requestClose()
+                } else {
+                    // The node did not shut down cleanly. Keep the
+                    // terminal open but ensure that it is disabled.
+                    nodeTerminalView.shutdown()
+                }
                 nodeController.dispose(config)
                 main.forceAtLeastOneTab()
             }

tools/demobench/src/main/kotlin/net/corda/demobench/views/NodeTerminalView.kt

@@ -229,16 +229,21 @@ class NodeTerminalView : Fragment() {
         }
     }
 
+    fun shutdown() {
+        header.isDisable = true
+        subscriptions.forEach {
+            // Don't allow any exceptions here to halt tab destruction.
+            try { it.unsubscribe() } catch (e: Exception) {}
+        }
+        webServer.close()
+        explorer.close()
+        viewer.close()
+        rpc?.close()
+    }
+
     fun destroy() {
         if (!isDestroyed) {
-            subscriptions.forEach {
+            shutdown()
-                // Don't allow any exceptions here to halt tab destruction.
-                try { it.unsubscribe() } catch (e: Exception) {}
-            }
-            webServer.close()
-            explorer.close()
-            viewer.close()
-            rpc?.close()
             pty?.close()
             isDestroyed = true
         }