Expose the rebuild preserve-ephemeral extension

This new extension permits preserving the ephemeral partition if the
Nova hypervisor supports that. This is primarily useful when Cinder is
not available to provide preservation of state while replacing the
image in use. One common situation for that is Nova Baremetal.

DocImpact
Blueprint: baremetal-preserve-ephemeral
Partial-Bug: #1174154
Co-Authored-By: Robert Collins <rbtcollins@hp.com>
Change-Id: Ib1511653904d4f95ab03fb471669175127004582

novaclient/tests/v1_1/test_servers.py

@@ -261,6 +261,15 @@ class ServersTest(utils.TestCase):
     def test_rebuild_server_disk_config_manual(self):
         self._rebuild_resize_disk_config('MANUAL')
 
+    def test_rebuild_server_preserve_ephemeral(self):
+        s = cs.servers.get(1234)
+        s.rebuild(image=1, preserve_ephemeral=True)
+        cs.assert_called('POST', '/servers/1234/action')
+        body = cs.client.callstack[-1][-1]
+        d = body['rebuild']
+        self.assertIn('preserve_ephemeral', d)
+        self.assertEqual(d['preserve_ephemeral'], True)
+
     def test_resize_server(self):
         s = cs.servers.get(1234)
         s.resize(flavor=1)

novaclient/tests/v1_1/test_shell.py

@@ -733,6 +733,27 @@ class ShellTest(utils.TestCase):
         self.assert_called('GET', '/flavors/1', pos=-2)
         self.assert_called('GET', '/images/2')
 
+    def test_rebuild_preserve_ephemeral(self):
+        self.run_command('rebuild sample-server 1 --preserve-ephemeral')
+        self.assert_called('GET', '/servers', pos=-8)
+        self.assert_called('GET', '/servers/1234', pos=-7)
+        self.assert_called('GET', '/images/1', pos=-6)
+        self.assert_called('POST', '/servers/1234/action',
+                           {'rebuild': {'imageRef': 1,
+                                        'preserve_ephemeral': True}}, pos=-5)
+        self.assert_called('GET', '/flavors/1', pos=-2)
+        self.assert_called('GET', '/images/2')
+
+        self.run_command('rebuild sample-server 1 --rebuild-password asdf')
+        self.assert_called('GET', '/servers', pos=-8)
+        self.assert_called('GET', '/servers/1234', pos=-7)
+        self.assert_called('GET', '/images/1', pos=-6)
+        self.assert_called('POST', '/servers/1234/action',
+                           {'rebuild': {'imageRef': 1, 'adminPass': 'asdf'}},
+                           pos=-5)
+        self.assert_called('GET', '/flavors/1', pos=-2)
+        self.assert_called('GET', '/images/2')
+
     def test_start(self):
         self.run_command('start sample-server')
         self.assert_called('POST', '/servers/1234/action', {'os-start': None})

novaclient/v1_1/servers.py

@@ -241,14 +241,18 @@ class Server(base.Resource):
         """
         self.manager.reboot(self, reboot_type)
 
-    def rebuild(self, image, password=None, **kwargs):
+    def rebuild(self, image, password=None, preserve_ephemeral=False,
+            **kwargs):
         """
         Rebuild -- shut down and then re-image -- this server.
 
         :param image: the :class:`Image` (or its ID) to re-image with.
         :param password: string to set as password on the rebuilt server.
+        :param preserve_ephemeral: If True, request that any ephemeral device
+            be preserved when rebuilding the instance. Defaults to False.
         """
-        return self.manager.rebuild(self, image, password=password, **kwargs)
+        return self.manager.rebuild(self, image, password=password,
+            preserve_ephemeral=preserve_ephemeral, **kwargs)
 
     def resize(self, flavor, **kwargs):
         """
@@ -748,7 +752,7 @@ class ServerManager(base.BootingManagerWithFind):
         self._action('reboot', server, {'type': reboot_type})
 
     def rebuild(self, server, image, password=None, disk_config=None,
-                **kwargs):
+                preserve_ephemeral=False, **kwargs):
         """
         Rebuild -- shut down and then re-image -- a server.
 
@@ -757,12 +761,16 @@ class ServerManager(base.BootingManagerWithFind):
         :param password: string to set as password on the rebuilt server.
         :param disk_config: partitioning mode to use on the rebuilt server.
                             Valid values are 'AUTO' or 'MANUAL'
+        :param preserve_ephemeral: If True, request that any ephemeral device
+            be preserved when rebuilding the instance. Defaults to False.
         """
         body = {'imageRef': base.getid(image)}
         if password is not None:
             body['adminPass'] = password
         if disk_config is not None:
             body['OS-DCF:diskConfig'] = disk_config
+        if preserve_ephemeral is not False:
+            body['preserve_ephemeral'] = True
 
         _resp, body = self._action('rebuild', server, body, **kwargs)
         return Server(self, body['server'])

novaclient/v1_1/shell.py

@@ -1207,6 +1207,10 @@ def do_reboot(cs, args):
     action="store_true",
     default=False,
     help='Skips flavor/image lookups when showing servers')
+@utils.arg('--preserve-ephemeral',
+    action="store_true",
+    default=False,
+    help='Preserve the default ephemeral storage partition on rebuild.')
 def do_rebuild(cs, args):
     """Shutdown, re-image, and re-boot a server."""
     server = _find_server(cs, args.server)
@@ -1218,6 +1222,7 @@ def do_rebuild(cs, args):
         _password = None
 
     kwargs = utils.get_resource_manager_extra_kwargs(do_rebuild, args)
+    kwargs['preserve_ephemeral'] = args.preserve_ephemeral
     server.rebuild(image, _password, **kwargs)
     _print_server(cs, args)