Microversion 2.56 - Enable cold migration with target host

Change-Id: I4deea811ffae3e7944d5ec10ca0bbf2bfa056a7c
Implements: blueprint cold-migration-with-target-queens

novaclient/__init__.py

@@ -25,4 +25,4 @@ API_MIN_VERSION = api_versions.APIVersion("2.1")
 # when client supported the max version, and bumped sequentially, otherwise
 # the client may break due to server side new version may include some
 # backward incompatible change.
-API_MAX_VERSION = api_versions.APIVersion("2.55")
+API_MAX_VERSION = api_versions.APIVersion("2.56")

novaclient/tests/unit/fixture_data/servers.py

@@ -452,6 +452,8 @@ class V1(Base):
             # but we can not specify version in data_fixture now and this is
             # V1 data, so just let it pass
             pass
+        elif action == 'migrate':
+            return None
         elif action == 'rebuild':
             body = body[action]
             adminPass = body.get('adminPass', 'randompassword')

novaclient/tests/unit/v2/fakes.py

@@ -687,7 +687,7 @@ class FakeSessionClient(base_client.SessionClient):
     # Server actions
     #
 
-    none_actions = ['revertResize', 'migrate', 'os-stop', 'os-start',
+    none_actions = ['revertResize', 'os-stop', 'os-start',
                     'forceDelete', 'restore', 'pause', 'unpause', 'unlock',
                     'unrescue', 'resume', 'suspend', 'lock', 'shelve',
                     'shelveOffload', 'unshelve', 'resetNetwork']
@@ -749,6 +749,15 @@ class FakeSessionClient(base_client.SessionClient):
             if self.api_version < api_versions.APIVersion("2.25"):
                 expected.add('disk_over_commit')
             assert set(body[action].keys()) == expected
+        elif action == 'migrate':
+            if self.api_version < api_versions.APIVersion("2.56"):
+                assert body[action] is None
+            else:
+                expected = set()
+                if 'host' in body[action].keys():
+                    # host can be optional
+                    expected.add('host')
+                assert set(body[action].keys()) == expected
         elif action == 'rebuild':
             body = body[action]
             adminPass = body.get('adminPass', 'randompassword')

novaclient/tests/unit/v2/test_servers.py

@@ -1581,3 +1581,26 @@ class ServersV254Test(ServersV252Test):
                                '1234', fakes.FAKE_IMAGE_UUID_1,
                                key_name='test_keypair')
         self.assertIn('key_name', six.text_type(ex.message))
+
+
+class ServersV256Test(ServersV254Test):
+
+    api_version = "2.56"
+
+    def test_migrate_server(self):
+        s = self.cs.servers.get(1234)
+        ret = s.migrate()
+        self.assert_request_id(ret, fakes.FAKE_REQUEST_ID_LIST)
+        self.assert_called('POST', '/servers/1234/action',
+                           {'migrate': {}})
+        ret = s.migrate(host='target-host')
+        self.assert_request_id(ret, fakes.FAKE_REQUEST_ID_LIST)
+        self.assert_called('POST', '/servers/1234/action',
+                           {'migrate': {'host': 'target-host'}})
+
+    def test_migrate_server_pre_256_fails(self):
+        self.cs.api_version = api_versions.APIVersion('2.55')
+        s = self.cs.servers.get(1234)
+        ex = self.assertRaises(TypeError,
+                               s.migrate, host='target-host')
+        self.assertIn('host', six.text_type(ex))

novaclient/tests/unit/v2/test_shell.py

@@ -1628,6 +1628,23 @@ class ShellTest(utils.TestCase):
         self.run_command('migrate sample-server')
         self.assert_called('POST', '/servers/1234/action', {'migrate': None})
 
+    def test_migrate_pre_v256(self):
+        self.assertRaises(SystemExit,
+                          self.run_command,
+                          'migrate --host target-host sample-server',
+                          api_version='2.55')
+
+    def test_migrate_v256(self):
+        self.run_command('migrate sample-server',
+                         api_version='2.56')
+        self.assert_called('POST', '/servers/1234/action',
+                           {'migrate': {}})
+
+        self.run_command('migrate --host target-host sample-server',
+                         api_version='2.56')
+        self.assert_called('POST', '/servers/1234/action',
+                           {'migrate': {'host': 'target-host'}})
+
     def test_resize(self):
         self.run_command('resize sample-server 1')
         self.assert_called('POST', '/servers/1234/action',

novaclient/v2/servers.py

@@ -327,6 +327,7 @@ class Server(base.Resource):
         """Diagnostics -- Retrieve server diagnostics."""
         return self.manager.diagnostics(self)
 
+    @api_versions.wraps("2.0", "2.55")
     def migrate(self):
         """
         Migrate a server to a new host.
@@ -335,6 +336,16 @@ class Server(base.Resource):
         """
         return self.manager.migrate(self)
 
+    @api_versions.wraps("2.56")
+    def migrate(self, host=None):
+        """
+        Migrate a server to a new host.
+
+        :param host: (Optional) The target host.
+        :returns: An instance of novaclient.base.TupleWithMeta
+        """
+        return self.manager.migrate(self, host=host)
+
     def remove_fixed_ip(self, address):
         """
         Remove an IP address.
@@ -1545,6 +1556,7 @@ class ServerManager(base.BootingManagerWithFind):
                                                        body, **kwargs)
         return Server(self, body['server'], resp=resp)
 
+    @api_versions.wraps("2.0", "2.55")
     def migrate(self, server):
         """
         Migrate a server to a new host.
@@ -1554,6 +1566,22 @@ class ServerManager(base.BootingManagerWithFind):
         """
         return self._action('migrate', server)
 
+    @api_versions.wraps("2.56")
+    def migrate(self, server, host=None):
+        """
+        Migrate a server to a new host.
+
+        :param server: The :class:`Server` (or its ID).
+        :param host: (Optional) The target host.
+        :returns: An instance of novaclient.base.TupleWithMeta
+        """
+        info = {}
+
+        if host:
+            info['host'] = host
+
+        return self._action('migrate', server, info)
+
     def resize(self, server, flavor, disk_config=None, **kwargs):
         """
         Resize a server's resources.

novaclient/v2/shell.py

@@ -1950,6 +1950,12 @@ def do_resize_revert(cs, args):
 
 
 @utils.arg('server', metavar='<server>', help=_('Name or ID of server.'))
+@utils.arg(
+    '--host',
+    metavar='<host>',
+    default=None,
+    help=_('Destination host name.'),
+    start_version='2.56')
 @utils.arg(
     '--poll',
     dest='poll',
@@ -1957,9 +1963,13 @@ def do_resize_revert(cs, args):
     default=False,
     help=_('Report the server migration progress until it completes.'))
 def do_migrate(cs, args):
-    """Migrate a server. The new host will be selected by the scheduler."""
+    """Migrate a server."""
+    update_kwargs = {}
+    if 'host' in args and args.host:
+        update_kwargs['host'] = args.host
+
     server = _find_server(cs, args.server)
-    server.migrate()
+    server.migrate(**update_kwargs)
 
     if args.poll:
         _poll_for_status(cs.servers.get, server.id, 'migrating',

releasenotes/notes/bp-cold-migration-with-target-queens-e361d4ae977aa396.yaml

@@ -0,0 +1,8 @@
+---
+features:
+  - Added a new ``--host`` option to ``nova migrate`` command
+    in microversion 2.56. It enables administrators to specify
+    a target host when cold migating a server. The target host will be
+    validated by the scheduler. The target host cannot be the same as
+    the current host on which the server is running and must be in the
+    same cell that the server is currently in.