Convert libvirt volume classes over to use config API

The classes in the libvirt/volume.py file build up XML
strings using printf style substitutions. Convert this
over to use the LibvirtConfigGuestDisk config class
instead

blueprint libvirt-xml-config-apis
Change-Id: Ied1fad47db6fb23b74edc4405015768c764a4d10
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

3 files changed, 49 insertions, 44 deletions

diff --git a/nova/tests/test_libvirt.py b/nova/tests/test_libvirt.py
index ce5009368..e749abb28 100644
--- a/nova/tests/test_libvirt.py
+++ b/nova/tests/test_libvirt.py
@@ -157,8 +157,8 @@ class LibvirtVolumeTestCase(test.TestCase):
                'provider_location': '%s,fake %s' % (location, iqn)}
         connection_info = vol_driver.initialize_connection(vol, self.connr)
         mount_device = "vde"
-        xml = libvirt_driver.connect_volume(connection_info, mount_device)
-        tree = ElementTree.fromstring(xml)
+        conf = libvirt_driver.connect_volume(connection_info, mount_device)
+        tree = conf.format_dom()
         dev_str = '/dev/disk/by-path/ip-%s-iscsi-%s-lun-0' % (location, iqn)
         self.assertEqual(tree.get('type'), 'block')
         self.assertEqual(tree.find('./source').get('dev'), dev_str)
@@ -196,8 +196,8 @@ class LibvirtVolumeTestCase(test.TestCase):
                'provider_location': '%s,fake %s' % (location, iqn)}
         connection_info = vol_driver.initialize_connection(vol, self.connr)
         mount_device = "vde"
-        xml = libvirt_driver.connect_volume(connection_info, mount_device)
-        tree = ElementTree.fromstring(xml)
+        conf = libvirt_driver.connect_volume(connection_info, mount_device)
+        tree = conf.format_dom()
         dev_str = '/dev/disk/by-path/ip-%s-iscsi-%s-lun-0' % (location, iqn)
         self.assertEqual(tree.get('type'), 'block')
         self.assertEqual(tree.find('./source').get('dev'), dev_str)
@@ -219,8 +219,8 @@ class LibvirtVolumeTestCase(test.TestCase):
         vol = {'id': 1, 'name': name}
         connection_info = vol_driver.initialize_connection(vol, self.connr)
         mount_device = "vde"
-        xml = libvirt_driver.connect_volume(connection_info, mount_device)
-        tree = ElementTree.fromstring(xml)
+        conf = libvirt_driver.connect_volume(connection_info, mount_device)
+        tree = conf.format_dom()
         self.assertEqual(tree.get('type'), 'network')
         self.assertEqual(tree.find('./source').get('protocol'), 'sheepdog')
         self.assertEqual(tree.find('./source').get('name'), name)
@@ -234,8 +234,8 @@ class LibvirtVolumeTestCase(test.TestCase):
         vol = {'id': 1, 'name': name}
         connection_info = vol_driver.initialize_connection(vol, self.connr)
         mount_device = "vde"
-        xml = libvirt_driver.connect_volume(connection_info, mount_device)
-        tree = ElementTree.fromstring(xml)
+        conf = libvirt_driver.connect_volume(connection_info, mount_device)
+        tree = conf.format_dom()
         self.assertEqual(tree.get('type'), 'network')
         self.assertEqual(tree.find('./source').get('protocol'), 'rbd')
         rbd_name = '%s/%s' % (FLAGS.rbd_pool, name)
@@ -256,8 +256,8 @@ class LibvirtVolumeTestCase(test.TestCase):
                'provider_location': '%s,fake %s' % (location, iqn)}
         connection_info = vol_driver.initialize_connection(vol, self.connr)
         mount_device = "vde"
-        xml = libvirt_driver.connect_volume(connection_info, mount_device)
-        tree = ElementTree.fromstring(xml)
+        conf = libvirt_driver.connect_volume(connection_info, mount_device)
+        tree = conf.format_dom()
         dev_str = '/dev/disk/by-path/ip-%s-iscsi-%s-lun-0' % (location, iqn)
         self.assertEqual(tree.get('type'), 'block')
         self.assertEqual(tree.find('./source').get('dev'), dev_str)
diff --git a/nova/virt/libvirt/connection.py b/nova/virt/libvirt/connection.py
index f1e04d3f9..043904ad6 100644
--- a/nova/virt/libvirt/connection.py
+++ b/nova/virt/libvirt/connection.py
@@ -504,15 +504,15 @@ class LibvirtConnection(driver.ComputeDriver):
     def attach_volume(self, connection_info, instance_name, mountpoint):
         virt_dom = self._lookup_by_name(instance_name)
         mount_device = mountpoint.rpartition("/")[2]
-        xml = self.volume_driver_method('connect_volume',
-                                        connection_info,
-                                        mount_device)
+        conf = self.volume_driver_method('connect_volume',
+                                         connection_info,
+                                         mount_device)
 
         if FLAGS.libvirt_type == 'lxc':
-            self._attach_lxc_volume(xml, virt_dom, instance_name)
+            self._attach_lxc_volume(conf.to_xml(), virt_dom, instance_name)
         else:
             try:
-                virt_dom.attachDevice(xml)
+                virt_dom.attachDevice(conf.to_xml())
             except Exception, ex:
                 self.volume_driver_method('disconnect_volume',
                                            connection_info,
@@ -1394,10 +1394,10 @@ class LibvirtConnection(driver.ComputeDriver):
         for vol in block_device_mapping:
             connection_info = vol['connection_info']
             mountpoint = vol['mount_device']
-            xml = self.volume_driver_method('connect_volume',
-                                            connection_info,
-                                            mountpoint)
-            volumes.append(xml)
+            conf = self.volume_driver_method('connect_volume',
+                                             connection_info,
+                                             mountpoint)
+            volumes.append(conf.to_xml())
 
         ebs_root = self._volume_in_mapping(self.default_root_device,
                                            block_device_info)
diff --git a/nova/virt/libvirt/volume.py b/nova/virt/libvirt/volume.py
index 784867eaf..38f8c2dd0 100644
--- a/nova/virt/libvirt/volume.py
+++ b/nova/virt/libvirt/volume.py
@@ -24,6 +24,7 @@ from nova import exception
 from nova import flags
 from nova import log as logging
 from nova import utils
+from nova.virt.libvirt import config
 
 LOG = logging.getLogger(__name__)
 FLAGS = flags.FLAGS
@@ -41,14 +42,15 @@ class LibvirtVolumeDriver(object):
 
     def connect_volume(self, connection_info, mount_device):
         """Connect the volume. Returns xml for libvirt."""
-        driver = self._pick_volume_driver()
-        device_path = connection_info['data']['device_path']
-        xml = """<disk type='block'>
-                     <driver name='%s' type='raw' cache='none'/>
-                     <source dev='%s'/>
-                     <target dev='%s' bus='virtio'/>
-                 </disk>""" % (driver, device_path, mount_device)
-        return xml
+        conf = config.LibvirtConfigGuestDisk()
+        conf.source_type = "block"
+        conf.driver_name = self._pick_volume_driver()
+        conf.driver_format = "raw"
+        conf.driver_cache = "none"
+        conf.source_path = connection_info['data']['device_path']
+        conf.target_dev = mount_device
+        conf.target_bus = "virtio"
+        return conf
 
     def disconnect_volume(self, connection_info, mount_device):
         """Disconnect the volume"""
@@ -59,29 +61,32 @@ class LibvirtFakeVolumeDriver(LibvirtVolumeDriver):
     """Driver to attach Network volumes to libvirt."""
 
     def connect_volume(self, connection_info, mount_device):
-        protocol = 'fake'
-        name = 'fake'
-        xml = """<disk type='network'>
-                     <driver name='qemu' type='raw' cache='none'/>
-                     <source protocol='%s' name='%s'/>
-                     <target dev='%s' bus='virtio'/>
-                 </disk>""" % (protocol, name, mount_device)
-        return xml
+        conf = config.LibvirtConfigGuestDisk()
+        conf.source_type = "network"
+        conf.driver_name = "qemu"
+        conf.driver_format = "raw"
+        conf.driver_cache = "none"
+        conf.source_protocol = "fake"
+        conf.source_host = "fake"
+        conf.target_dev = mount_device
+        conf.target_bus = "virtio"
+        return conf
 
 
 class LibvirtNetVolumeDriver(LibvirtVolumeDriver):
     """Driver to attach Network volumes to libvirt."""
 
     def connect_volume(self, connection_info, mount_device):
-        driver = self._pick_volume_driver()
-        protocol = connection_info['driver_volume_type']
-        name = connection_info['data']['name']
-        xml = """<disk type='network'>
-                     <driver name='%s' type='raw' cache='none'/>
-                     <source protocol='%s' name='%s'/>
-                     <target dev='%s' bus='virtio'/>
-                 </disk>""" % (driver, protocol, name, mount_device)
-        return xml
+        conf = config.LibvirtConfigGuestDisk()
+        conf.source_type = "network"
+        conf.driver_name = self._pick_volume_driver()
+        conf.driver_format = "raw"
+        conf.driver_cache = "none"
+        conf.source_protocol = connection_info['driver_volume_type']
+        conf.source_host = connection_info['data']['name']
+        conf.target_dev = mount_device
+        conf.target_bus = "virtio"
+        return conf
 
 
 class LibvirtISCSIVolumeDriver(LibvirtVolumeDriver):