Cleanup exception handling

Make sure stack traces are not cut short. Make sure there's only one
exception handler per function (otherwise new exception covers the old one).
Fixes bug 1053421

Change-Id: Id1ff84a5ba3eaeef6385b311773bde784672e1f9

4 files changed, 19 insertions, 14 deletions

diff --git a/nova/api/openstack/compute/contrib/floating_ips.py b/nova/api/openstack/compute/contrib/floating_ips.py
index f3692e02e..be952eb8a 100644
--- a/nova/api/openstack/compute/contrib/floating_ips.py
+++ b/nova/api/openstack/compute/contrib/floating_ips.py
@@ -175,7 +175,7 @@ class FloatingIPController(object):
                 nmfi.message = _("No more floating ips in pool %s.") % pool
             else:
                 nmfi.message = _("No more floating ips available.")
-            raise nmfi
+            raise
 
         return _translate_floating_ip_view(ip)
 
diff --git a/nova/virt/hyperv/vmops.py b/nova/virt/hyperv/vmops.py
index af6f9cfbf..8c86016c2 100644
--- a/nova/virt/hyperv/vmops.py
+++ b/nova/virt/hyperv/vmops.py
@@ -157,7 +157,7 @@ class VMOps(baseops.BaseOps):
         except Exception as exn:
             LOG.exception(_('spawn vm failed: %s'), exn)
             self.destroy(instance)
-            raise exn
+            raise
 
     def _create_vm(self, instance):
         """Create a VM but don't start it.  """
diff --git a/nova/virt/libvirt/driver.py b/nova/virt/libvirt/driver.py
index 567ed6ec8..7e828163c 100644
--- a/nova/virt/libvirt/driver.py
+++ b/nova/virt/libvirt/driver.py
@@ -1183,11 +1183,11 @@ class LibvirtDriver(driver.ComputeDriver):
             else:
                 LOG.error(_("Error on '%(path)s' while checking direct I/O: "
                             "'%(ex)s'") % {'path': dirpath, 'ex': str(e)})
-                raise e
+                raise
         except Exception, e:
             LOG.error(_("Error on '%(path)s' while checking direct I/O: "
                         "'%(ex)s'") % {'path': dirpath, 'ex': str(e)})
-            raise e
+            raise
         finally:
             try:
                 os.unlink(testfile)
@@ -2764,6 +2764,16 @@ class LibvirtDriver(driver.ComputeDriver):
         """Manage the local cache of images."""
         self.image_cache_manager.verify_base_images(context)
 
+    def _cleanup_remote_migration(self, dest, inst_base, inst_base_resize):
+        """Used only for cleanup in case migrate_disk_and_power_off fails"""
+        try:
+            if os.path.exists(inst_base_resize):
+                utils.execute('rm', '-rf', inst_base)
+                utils.execute('mv', inst_base_resize, inst_base)
+                utils.execute('ssh', dest, 'rm', '-rf', inst_base)
+        except Exception:
+            pass
+
     @exception.wrap_exception()
     def migrate_disk_and_power_off(self, context, instance, dest,
                                    instance_type, network_info,
@@ -2816,15 +2826,10 @@ class LibvirtDriver(driver.ComputeDriver):
 
                 else:  # raw or qcow2 with no backing file
                     libvirt_utils.copy_image(from_path, img_path, host=dest)
-        except Exception, e:
-            try:
-                if os.path.exists(inst_base_resize):
-                    utils.execute('rm', '-rf', inst_base)
-                    utils.execute('mv', inst_base_resize, inst_base)
-                    utils.execute('ssh', dest, 'rm', '-rf', inst_base)
-            except Exception:
-                pass
-            raise e
+        except Exception:
+            with excutils.save_and_reraise_exception():
+                self._cleanup_remote_migration(dest, inst_base,
+                                               inst_base_resize)
 
         return disk_info_text
 
diff --git a/nova/virt/xenapi/vm_utils.py b/nova/virt/xenapi/vm_utils.py
index 03a86415c..a9adb4575 100644
--- a/nova/virt/xenapi/vm_utils.py
+++ b/nova/virt/xenapi/vm_utils.py
@@ -1148,7 +1148,7 @@ def _fetch_disk_image(context, session, instance, name_label, image_id,
         e.args = e.args + ([dict(type=ImageType.to_string(image_type),
                                  uuid=vdi_uuid,
                                  file=filename)],)
-        raise e
+        raise
 
 
 def determine_disk_image_type(image_meta):