Added SocketOpen retryable predicate for connecting to ssh

Some refactoring, including use of guava's checkState and more precise method parameters

aws/demos/resize-ebs/resize-ebs-java/pom.xml

@@ -30,7 +30,7 @@
 	<artifactId>jclouds-aws-demo-ebsresize</artifactId>
 	<groupId>org.jclouds</groupId>
 
-    <name>jclouds EC2 example, to change volume size for EBS-based instances</name>
+    <name>jclouds EC2 demo, to change volume size for EBS-based instances</name>
 	<description>For a given running instance, resizes the volume (with several minutes of downtime)</description>
 
     <repositories>

aws/demos/resize-ebs/resize-ebs-java/src/main/java/org/jclouds/tools/ebsresize/InstanceVolumeManager.java

@@ -19,6 +19,10 @@
 
 package org.jclouds.tools.ebsresize;
 
+import static com.google.common.base.Preconditions.checkState;
+
+import com.google.common.base.Predicate;
+import com.google.common.collect.Iterables;
 import org.jclouds.aws.domain.Region;
 import org.jclouds.aws.ec2.EC2AsyncClient;
 import org.jclouds.aws.ec2.EC2Client;
@@ -30,13 +34,17 @@ import org.jclouds.compute.domain.ComputeMetadata;
 import org.jclouds.compute.domain.NodeMetadata;
 import org.jclouds.compute.domain.internal.NodeMetadataImpl;
 import org.jclouds.domain.Credentials;
+import org.jclouds.predicates.RetryablePredicate;
+import org.jclouds.predicates.SocketOpen;
 import org.jclouds.rest.RestContext;
 import org.jclouds.tools.ebsresize.facade.ElasticBlockStoreFacade;
 import org.jclouds.tools.ebsresize.facade.InstanceFacade;
 import org.jclouds.tools.ebsresize.util.SshExecutor;
 
 import java.io.IOException;
+import java.net.InetSocketAddress;
 import java.util.Map;
+import java.util.concurrent.TimeUnit;
 
 /**
  * Launches a sequence of commands to change the size of
@@ -59,6 +67,8 @@ public class InstanceVolumeManager {
     private final EC2Client api;
     private final ElasticBlockStoreFacade ebsApi;
     private final InstanceFacade instanceApi;
+    private final Predicate<InetSocketAddress> socketOpen =
+                new RetryablePredicate<InetSocketAddress>(new SocketOpen(), 180, 5, TimeUnit.SECONDS);
 
     public InstanceVolumeManager(String accessKeyId, String secretKey) {
 
@@ -92,14 +102,6 @@ public class InstanceVolumeManager {
 
         api.getElasticBlockStoreServices().deleteVolumeInRegion(instance.getRegion(), volume.getId());
 
-        //TODO: how to know that an instance is available for SSH for certain?
-        // sometimes 20 seconds is enough after it started, sometimes it isn't
-        try {
-            Thread.sleep(20000);
-        } catch(InterruptedException e) {
-            e.printStackTrace();
-        }
-
         runRemoteResizeCommands(instance, instanceCredentials, pathToKeyPair);
     }
 
@@ -112,8 +114,14 @@ public class InstanceVolumeManager {
         NodeMetadata nodeMetadata = addCredentials((NodeMetadata) nodes.get(instance.getId()),
                 instanceCredentials);
 
+        InetSocketAddress socket =
+                new InetSocketAddress(Iterables.getLast(nodeMetadata.getPublicAddresses()), 22);
+
         SshExecutor sshExecutor = new SshExecutor(nodeMetadata, instanceCredentials,
-                                                    keyPair, instance);
+                                                    keyPair, socket);
+
+        waitForSocket(socket);
+
         sshExecutor.connect();
         sshExecutor.execute("sudo resize2fs " + instance.getRootDeviceName());
     }
@@ -129,6 +137,11 @@ public class InstanceVolumeManager {
                 credentials);
     }
 
+    public void waitForSocket(InetSocketAddress socket) {
+        checkState(socketOpen.apply(socket),
+                            /*or throw*/ "Couldn't connect to instance");
+    }
+
     public ElasticBlockStoreFacade getEbsApi() {
         return ebsApi;
     }

aws/demos/resize-ebs/resize-ebs-java/src/main/java/org/jclouds/tools/ebsresize/facade/ElasticBlockStoreFacade.java

@@ -99,7 +99,8 @@ public class ElasticBlockStoreFacade {
     public void detachVolumeFromStoppedInstance(Volume volume, RunningInstance stoppedInstance) {
         elasticBlockStoreServices.detachVolumeInRegion(stoppedInstance.getRegion(), volume.getId(), false,
                 DetachVolumeOptions.Builder.fromInstance(stoppedInstance.getId()));
-        assertTrue(volumeAvailable.apply(volume));
+        checkState(volumeAvailable.apply(volume),
+                                /*or throw*/ "Couldn't detach the volume from instance");
     }
 
     /**
@@ -117,12 +118,14 @@ public class ElasticBlockStoreFacade {
         Snapshot createdSnapshot =
                 elasticBlockStoreServices.createSnapshotInRegion(volume.getRegion(), volume.getId(),
                 CreateSnapshotOptions.Builder.withDescription("snapshot to test extending volumes"));
-        assertTrue(snapshotCompleted.apply(createdSnapshot));
+        checkState(snapshotCompleted.apply(createdSnapshot),
+                                            /*or throw*/ "Couldn't create a snapshot");
 
         Volume newVolume = elasticBlockStoreServices.createVolumeFromSnapshotInAvailabilityZone(
                 volume.getAvailabilityZone(), newSize,
                 createdSnapshot.getId());
-        assertTrue(volumeAvailable.apply(newVolume));
+        checkState(volumeAvailable.apply(newVolume),
+                                /*or throw*/ "Couldn't create a volume from the snapshot");
 
         return newVolume;
     }
@@ -141,10 +144,7 @@ public class ElasticBlockStoreFacade {
         Attachment volumeAttachment = elasticBlockStoreServices.
                         attachVolumeInRegion(instance.getRegion(), volume.getId(), instance.getId(),
                                         instance.getRootDeviceName());
-        assertTrue(volumeAttached.apply(volumeAttachment));
+        checkState(volumeAttached.apply(volumeAttachment),
-    }
+                                    /*or throw*/ "Couldn't attach volume back to the instance");
-
-    public void assertTrue(boolean value) {
-        if(!value) throw new RuntimeException("Found false, expected true");
     }
 }

aws/demos/resize-ebs/resize-ebs-java/src/main/java/org/jclouds/tools/ebsresize/facade/InstanceFacade.java

@@ -69,7 +69,8 @@ public class InstanceFacade {
      */
     public void startInstance(RunningInstance instance) {
         instanceServices.startInstancesInRegion(instance.getRegion(), instance.getId());
-        assertTrue(instanceRunning.apply(instance));
+        checkState(instanceRunning.apply(instance),
+                /*or throw*/ "Couldn't start the instance");
     }
 
      /**
@@ -84,7 +85,8 @@ public class InstanceFacade {
      */
     public void stopInstance(RunningInstance instance) {
         instanceServices.stopInstancesInRegion(instance.getRegion(), false, instance.getId());
-        assertTrue(instanceStopped.apply(instance));
+        checkState(instanceStopped.apply(instance),
+                            /*or throw*/ "Couldn't stop the instance");
     }
 
     /**
@@ -99,9 +101,5 @@ public class InstanceFacade {
         Reservation reservation = checkNotNull(Iterables.getOnlyElement(reservations));
         return Iterables.getOnlyElement(reservation);
     }
-
-    public void assertTrue(boolean value) {
-        if(!value) throw new RuntimeException("Found false, expected true");
-    }
     
 }

aws/demos/resize-ebs/resize-ebs-java/src/main/java/org/jclouds/tools/ebsresize/util/SshExecutor.java

@@ -35,6 +35,15 @@ import java.net.InetSocketAddress;
 import java.util.concurrent.TimeUnit;
 
 /**
+ * Allows remote command execution on instance.
+ *
+ * This is based on {@link org.jclouds.ssh.SshClient} and
+ * {@link org.jclouds.compute.util.ComputeUtils}, with
+ * some convenience methods.
+ *
+ * @see org.jclouds.ssh.SshClient
+ * @see org.jclouds.compute.util.ComputeUtils 
+ *
  * @author Oleksiy Yarmula
  */
 public class SshExecutor {
@@ -46,21 +55,19 @@ public class SshExecutor {
     private final NodeMetadata nodeMetadata;
     private final Credentials instanceCredentials;
     private final String keyPair;
-    private final RunningInstance instance;
     private final SshClient sshClient;
     private final ComputeUtils utils;
 
     public SshExecutor(NodeMetadata nodeMetadata,
                        Credentials instanceCredentials,
                        String keyPair,
-                       RunningInstance instance) {
+                       InetSocketAddress socket) {
         this.nodeMetadata = nodeMetadata;
         this.instanceCredentials = instanceCredentials;
         this.keyPair = keyPair;
-        this.instance = instance;
 
         this.sshClient =
-                new JschSshClient(new InetSocketAddress(instance.getDnsName(), 22), 60000,
+                new JschSshClient(socket, 60000,
                                 instanceCredentials.account, keyPair.getBytes());
 
         this.utils = new ComputeUtils(null, runScriptRunning, null);