In preparation for XenAPI support, refactor the interface between

nova.compute and the hypervisor (i.e. libvirt).

compute.node is no longer coupled tightly with libvirt.  Instead, hypervisor
connections are handled through a simple abstract interface.   This has the
additional advantage that there is no need to riddle the code with
FLAGS.fake_libvirt checks, as we now have an interface behind which we can mock.

The libvirt-specific code, and the fakevirt code used for unit tests, have
moved into nova.virt.

The fake_libvirt flag has been replaced with a connection_type flag, that will
allow us to specify different connection types.

The disk image handling (S3 or local disk image fetch) has moved into
nova.virt.images, where it will be easier to share between connection types.

The power_state values (Instance.RUNNING etc) and the INSTANCE_TYPES dictionary
have moved into their own files (nova.compute.instance_types and
nova.compute.power_state) so that we can share them without mutual
dependencies between nova.compute.node and nova.virt.libvirt_conn.

bin/dhcpleasor.py

@@ -71,7 +71,7 @@ def main(argv=None):
         FLAGS.fake_rabbit = True
         FLAGS.redis_db = 8
         FLAGS.network_size = 32
-        FLAGS.fake_libvirt=True
+        FLAGS.connection_type = 'fake'
         FLAGS.fake_network=True
         FLAGS.fake_users = True
     action = argv[1]

docs/fakes.rst

@@ -18,10 +18,10 @@
 Nova Fakes
 ==========
 
-The :mod:`fakevirt` Module
+The :mod:`virt.fake` Module
 --------------------------
 
-.. automodule:: nova.fakevirt
+.. automodule:: nova.virt.fake
     :members:
     :undoc-members:
     :show-inheritance:

nova/endpoint/cloud.py

@@ -39,6 +39,7 @@ from nova.auth import users
 from nova.compute import model
 from nova.compute import network
 from nova.compute import node
+from nova.compute.instance_types import INSTANCE_TYPES
 from nova.endpoint import images
 from nova.volume import storage
 
@@ -103,7 +104,7 @@ class CloudController(object):
         result = {}
         for instance in self.instdir.all:
             if instance['project_id'] == project_id:
-                line = '%s slots=%d' % (instance['private_dns_name'], node.INSTANCE_TYPES[instance['instance_type']]['vcpus'])
+                line = '%s slots=%d' % (instance['private_dns_name'], INSTANCE_TYPES[instance['instance_type']]['vcpus'])
                 if instance['key_name'] in result:
                     result[instance['key_name']].append(line)
                 else:

nova/fakevirt.py

@@ -1,112 +0,0 @@
-# vim: tabstop=4 shiftwidth=4 softtabstop=4
-
-# Copyright 2010 United States Government as represented by the
-# Administrator of the National Aeronautics and Space Administration.
-# All Rights Reserved.
-#
-#    Licensed under the Apache License, Version 2.0 (the "License"); you may
-#    not use this file except in compliance with the License. You may obtain
-#    a copy of the License at
-#
-#         http://www.apache.org/licenses/LICENSE-2.0
-#
-#    Unless required by applicable law or agreed to in writing, software
-#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
-#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
-#    License for the specific language governing permissions and limitations
-#    under the License.
-
-"""
-A fake (in-memory) hypervisor+api. Allows nova testing w/o KVM and libvirt.
-"""
-
-import StringIO
-from xml.etree import ElementTree
-
-
-class FakeVirtConnection(object):
-    # FIXME: networkCreateXML, listNetworks don't do anything since
-    # they aren't exercised in tests yet
-
-    def __init__(self):
-        self.next_index = 0
-        self.instances = {}
-
-    @classmethod
-    def instance(cls):
-        if not hasattr(cls, '_instance'):
-            cls._instance = cls()
-        return cls._instance
-
-    def lookupByID(self, i):
-        return self.instances[str(i)]
-
-    def listDomainsID(self):
-        return self.instances.keys()
-
-    def listNetworks(self):
-        return []
-
-    def lookupByName(self, instance_id):
-        for x in self.instances.values():
-            if x.name() == instance_id:
-                return x
-        raise Exception('no instance found for instance_id: %s' % instance_id)
-
-    def networkCreateXML(self, xml):
-        pass
-
-    def createXML(self, xml, flags):
-        # parse the xml :(
-        xml_stringio = StringIO.StringIO(xml)
-
-        my_xml = ElementTree.parse(xml_stringio)
-        name = my_xml.find('name').text
-
-        fake_instance = FakeVirtInstance(conn=self,
-                                         index=str(self.next_index),
-                                         name=name,
-                                         xml=my_xml)
-        self.instances[str(self.next_index)] = fake_instance
-        self.next_index += 1
-
-    def _removeInstance(self, i):
-        self.instances.pop(str(i))
-
-
-class FakeVirtInstance(object):
-    NOSTATE = 0x00
-    RUNNING = 0x01
-    BLOCKED = 0x02
-    PAUSED = 0x03
-    SHUTDOWN = 0x04
-    SHUTOFF = 0x05
-    CRASHED = 0x06
-
-    def __init__(self, conn, index, name, xml):
-        self._conn = conn
-        self._destroyed = False
-        self._name = name
-        self._index = index
-        self._state = self.RUNNING
-
-    def name(self):
-        return self._name
-
-    def destroy(self):
-        if self._state == self.SHUTOFF:
-            raise Exception('instance already destroyed: %s' % self.name())
-        self._state = self.SHUTDOWN
-        self._conn._removeInstance(self._index)
-
-    def info(self):
-        return [self._state, 0, 2, 0, 0]
-
-    def XMLDesc(self, flags):
-        return open('fakevirtinstance.xml', 'r').read()
-
-    def blockStats(self, disk):
-        return [0L, 0L, 0L, 0L, null]
-
-    def interfaceStats(self, iface):
-        return [0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L]

nova/flags.py

@@ -36,14 +36,13 @@ DEFINE_bool = DEFINE_bool
 # Define any app-specific flags in their own files, docs at:
 # http://code.google.com/p/python-gflags/source/browse/trunk/gflags.py#39
 
+DEFINE_string('connection_type', 'libvirt', 'libvirt or fake')
 DEFINE_integer('s3_port', 3333, 's3 port')
 DEFINE_integer('s3_internal_port', 3334, 's3 port')
 DEFINE_string('s3_host', '127.0.0.1', 's3 host')
 #DEFINE_string('cloud_topic', 'cloud', 'the topic clouds listen on')
 DEFINE_string('compute_topic', 'compute', 'the topic compute nodes listen on')
 DEFINE_string('storage_topic', 'storage', 'the topic storage nodes listen on')
-DEFINE_bool('fake_libvirt', False,
-                  'whether to use a fake libvirt or not')
 DEFINE_bool('verbose', False, 'show debug output')
 DEFINE_boolean('fake_rabbit', False, 'use a fake rabbit')
 DEFINE_bool('fake_network', False, 'should we use fake network devices and addresses')

nova/tests/access_unittest.py

@@ -33,7 +33,7 @@ class Context(object):
 class AccessTestCase(test.BaseTestCase):
     def setUp(self):
         super(AccessTestCase, self).setUp()
-        FLAGS.fake_libvirt = True
+        FLAGS.connection_type = 'fake'
         FLAGS.fake_storage = True
         um = UserManager.instance()
         # Make test users

nova/tests/cloud_unittest.py

@@ -39,7 +39,7 @@ FLAGS = flags.FLAGS
 class CloudTestCase(test.BaseTestCase):
     def setUp(self):
         super(CloudTestCase, self).setUp()
-        self.flags(fake_libvirt=True,
+        self.flags(connection_type='fake',
                    fake_storage=True,
                    fake_users=True)
 
@@ -72,7 +72,7 @@ class CloudTestCase(test.BaseTestCase):
         users.UserManager.instance().delete_user('admin')
 
     def test_console_output(self):
-        if FLAGS.fake_libvirt:
+        if FLAGS.connection_type == 'fake':
             logging.debug("Can't test instances without a real virtual env.")
             return
         instance_id = 'foo'
@@ -83,7 +83,7 @@ class CloudTestCase(test.BaseTestCase):
         rv = yield self.node.terminate_instance(instance_id)
 
     def test_run_instances(self):
-        if FLAGS.fake_libvirt:
+        if FLAGS.connection_type == 'fake':
             logging.debug("Can't test instances without a real virtual env.")
             return
         image_id = FLAGS.default_image
@@ -104,7 +104,7 @@ class CloudTestCase(test.BaseTestCase):
                 break
         self.assert_(rv)
 
-        if not FLAGS.fake_libvirt:
+        if connection_type != 'fake':
             time.sleep(45) # Should use boto for polling here
         for reservations in rv['reservationSet']:
             # for res_id in reservations.keys():

nova/tests/fake_flags.py

@@ -20,7 +20,7 @@ from nova import flags
 
 FLAGS = flags.FLAGS
 
-FLAGS.fake_libvirt = True
+FLAGS.connection_type = 'fake'
 FLAGS.fake_storage = True
 FLAGS.fake_rabbit = True
 FLAGS.fake_network = True

nova/tests/future_unittest.py

@@ -39,7 +39,7 @@ FLAGS = flags.FLAGS
 class AdminTestCase(test.BaseTestCase):
     def setUp(self):
         super(AdminTestCase, self).setUp()
-        self.flags(fake_libvirt=True,
+        self.flags(connection_type='fake',
                    fake_rabbit=True)
 
         self.conn = rpc.Connection.instance()

nova/tests/model_unittest.py

@@ -34,7 +34,7 @@ FLAGS = flags.FLAGS
 class ModelTestCase(test.TrialTestCase):
     def setUp(self):
         super(ModelTestCase, self).setUp()
-        self.flags(fake_libvirt=True,
+        self.flags(connection_type='fake',
                    fake_storage=True,
                    fake_users=True)
 

nova/tests/network_unittest.py

@@ -33,7 +33,7 @@ from nova import utils
 class NetworkTestCase(test.TrialTestCase):
     def setUp(self):
         super(NetworkTestCase, self).setUp()
-        self.flags(fake_libvirt=True,
+        self.flags(connection_type='fake',
                    fake_storage=True,
                    fake_network=True,
                    network_size=32)

nova/tests/node_unittest.py

@@ -57,7 +57,7 @@ class NodeConnectionTestCase(test.TrialTestCase):
     def setUp(self):
         logging.getLogger().setLevel(logging.DEBUG)
         super(NodeConnectionTestCase, self).setUp()
-        self.flags(fake_libvirt=True,
+        self.flags(connection_type='fake',
                    fake_storage=True,
                    fake_users=True)
         self.node = node.Node()

nova/tests/objectstore_unittest.py

@@ -25,6 +25,8 @@ import tempfile
 
 from nova import flags
 from nova import objectstore
+from nova.objectstore import bucket # for buckets_path flag
+from nova.objectstore import image # for images_path flag
 from nova import test
 from nova.auth import users
 

nova/tests/real_flags.py

@@ -20,7 +20,7 @@ from nova import flags
 
 FLAGS = flags.FLAGS
 
-FLAGS.fake_libvirt = False
+FLAGS.connection_type = 'libvirt'
 FLAGS.fake_storage = False
 FLAGS.fake_rabbit = False
 FLAGS.fake_network = False

nova/tests/storage_unittest.py

@@ -34,7 +34,7 @@ class StorageTestCase(test.TrialTestCase):
         super(StorageTestCase, self).setUp()
         self.mynode = node.Node()
         self.mystorage = None
-        self.flags(fake_libvirt=True,
+        self.flags(connection_type='fake',
                    fake_storage=True)
         self.mystorage = storage.BlockStore()
 

nova/tests/users_unittest.py

@@ -35,7 +35,7 @@ class UserTestCase(test.BaseTestCase):
     flush_db = False
     def setUp(self):
         super(UserTestCase, self).setUp()
-        self.flags(fake_libvirt=True,
+        self.flags(connection_type='fake',
                    fake_storage=True)
         self.users = users.UserManager.instance()