CS-1879: NPE while migrating volume. The state transitions on the volume that has to be migrated were incorrect. A volume to be migrated is in ready state and cannot be transitioned to copying state. Similarly, the duplicated volume is in ready state too and cannot be transitioned to creating state. Fixed it by transitioning the volume to migrating state when a migrateVolume api call is made. Also, a volume has to be destroyed first before it can be expunged. Fixed that too.

devdeep · Abhinandan Prateek · commit b01f63123fff · 2013-04-19T16:15:24.000+05:30
Signed-off-by: Abhinandan Prateek &lt;aprateek@apache.org&gt;
diff --git a/engine/storage/volume/src/org/apache/cloudstack/storage/volume/VolumeServiceImpl.java b/engine/storage/volume/src/org/apache/cloudstack/storage/volume/VolumeServiceImpl.java
@@ -521,8 +521,8 @@ public AsyncCallFuture<VolumeApiResult> copyVolume(VolumeInfo srcVolume,
 
             VolumeVO destVol = duplicateVolumeOnAnotherStorage(srcVolume, (StoragePool)destStore);
             VolumeInfo destVolume = this.volFactory.getVolume(destVol.getId(), destStore);
-            destVolume.processEvent(Event.CreateOnlyRequested);
-            srcVolume.processEvent(Event.CopyingRequested);
+            destVolume.processEvent(Event.MigrationRequested);
+            srcVolume.processEvent(Event.MigrationRequested);
 
             CopyVolumeContext<VolumeApiResult> context = new CopyVolumeContext<VolumeApiResult>(null, future, srcVolume, 
                     destVolume,
@@ -550,13 +550,17 @@ protected Void copyVolumeCallBack(AsyncCallbackDispatcher<VolumeServiceImpl, Cop
                 res.setResult(result.getResult());
                 destVolume.processEvent(Event.OperationFailed);
                 srcVolume.processEvent(Event.OperationFailed);
+                destroyVolume(destVolume.getId());
+                destVolume = this.volFactory.getVolume(destVolume.getId());
                 AsyncCallFuture<VolumeApiResult> destroyFuture = this.expungeVolumeAsync(destVolume);
                 destroyFuture.get();
                 future.complete(res);
                 return null;
             }
             srcVolume.processEvent(Event.OperationSuccessed);
             destVolume.processEvent(Event.OperationSuccessed);
+            destroyVolume(srcVolume.getId());
+            srcVolume = this.volFactory.getVolume(srcVolume.getId());
             AsyncCallFuture<VolumeApiResult> destroyFuture = this.expungeVolumeAsync(srcVolume);
             destroyFuture.get();
             future.complete(res);
