Centralize instance directory logic.

This is the first step to being able to change the name of the instance
directories to something more unique than instance name.

Sneaks up on bug 1023865.

Change-Id: I1340a6b8644680325cba1e90a208e4be33ace6b4

nova/tests/fake_imagebackend.py

@@ -28,7 +28,7 @@ class Backend(object):
     def image(self, instance, name, image_type=''):
         class FakeImage(imagebackend.Image):
             def __init__(self, instance, name):
-                self.path = os.path.join(instance, name)
+                self.path = os.path.join(instance['name'], name)
 
             def create_image(self, prepare_template, base,
                               size, *args, **kwargs):

nova/tests/fake_libvirt_utils.py

@@ -17,6 +17,12 @@
 import os
 import StringIO
 
+from nova.openstack.common import cfg
+
+
+CONF = cfg.CONF
+CONF.import_opt('instances_path', 'nova.compute.manager')
+
 
 files = {'console.log': True}
 disk_sizes = {}
@@ -133,3 +139,8 @@ def get_fs_info(path):
 
 def fetch_image(context, target, image_id, user_id, project_id):
     pass
+
+
+def get_instance_path(instance):
+    # TODO(mikal): we should really just call the real one here
+    return os.path.join(CONF.instances_path, instance['name'])

nova/tests/test_imagebackend.py

@@ -22,6 +22,7 @@ from nova.openstack.common import cfg
 from nova import test
 from nova.tests import fake_libvirt_utils
 from nova.virt.libvirt import imagebackend
+from nova.virt.libvirt import utils as libvirt_utils
 
 CONF = cfg.CONF
 
@@ -38,12 +39,12 @@ class _ImageTestCase(object):
         super(_ImageTestCase, self).setUp()
         self.flags(disable_process_locking=True,
                    instances_path=self.INSTANCES_PATH)
-        self.INSTANCE = 'instance'
+        self.INSTANCE = {'name': 'instance'}
         self.NAME = 'fake.vm'
         self.TEMPLATE = 'template'
 
-        self.PATH = os.path.join(CONF.instances_path, self.INSTANCE,
-                                 self.NAME)
+        self.PATH = os.path.join(
+            libvirt_utils.get_instance_path(self.INSTANCE), self.NAME)
         self.TEMPLATE_DIR = os.path.join(CONF.instances_path,
                                          '_base')
         self.TEMPLATE_PATH = os.path.join(self.TEMPLATE_DIR, 'template')
@@ -215,7 +216,7 @@ class LvmTestCase(_ImageTestCase, test.TestCase):
         self.image_class = imagebackend.Lvm
         super(LvmTestCase, self).setUp()
         self.flags(libvirt_images_volume_group=self.VG)
-        self.LV = '%s_%s' % (self.INSTANCE, self.NAME)
+        self.LV = '%s_%s' % (self.INSTANCE['name'], self.NAME)
         self.PATH = os.path.join('/dev', self.VG, self.LV)
 
         self.disk = imagebackend.disk
@@ -342,7 +343,7 @@ class LvmTestCase(_ImageTestCase, test.TestCase):
 
 
 class BackendTestCase(test.TestCase):
-    INSTANCE = 'fake-instance'
+    INSTANCE = {'name': 'fake-instance'}
     NAME = 'fake-name.suffix'
 
     def get_image(self, use_cow, image_type):

nova/tests/test_libvirt.py

@@ -478,7 +478,8 @@ class CacheConcurrencyTestCase(test.TestCase):
         wait1 = eventlet.event.Event()
         done1 = eventlet.event.Event()
         sig1 = eventlet.event.Event()
-        thr1 = eventlet.spawn(backend.image('instance', 'name').cache,
+        thr1 = eventlet.spawn(backend.image({'name': 'instance'},
+                                            'name').cache,
                 _concurrency, 'fname', None,
                 signal=sig1, wait=wait1, done=done1)
         eventlet.sleep(0)
@@ -488,7 +489,8 @@ class CacheConcurrencyTestCase(test.TestCase):
         wait2 = eventlet.event.Event()
         done2 = eventlet.event.Event()
         sig2 = eventlet.event.Event()
-        thr2 = eventlet.spawn(backend.image('instance', 'name').cache,
+        thr2 = eventlet.spawn(backend.image({'name': 'instance'},
+                                            'name').cache,
                 _concurrency, 'fname', None,
                 signal=sig2, wait=wait2, done=done2)
 
@@ -512,7 +514,8 @@ class CacheConcurrencyTestCase(test.TestCase):
         wait1 = eventlet.event.Event()
         done1 = eventlet.event.Event()
         sig1 = eventlet.event.Event()
-        thr1 = eventlet.spawn(backend.image('instance', 'name').cache,
+        thr1 = eventlet.spawn(backend.image({'name': 'instance'},
+                                            'name').cache,
                 _concurrency, 'fname2', None,
                 signal=sig1, wait=wait1, done=done1)
         eventlet.sleep(0)
@@ -522,7 +525,8 @@ class CacheConcurrencyTestCase(test.TestCase):
         wait2 = eventlet.event.Event()
         done2 = eventlet.event.Event()
         sig2 = eventlet.event.Event()
-        thr2 = eventlet.spawn(backend.image('instance', 'name').cache,
+        thr2 = eventlet.spawn(backend.image({'name': 'instance'},
+                                            'name').cache,
                 _concurrency, 'fname1', None,
                 signal=sig2, wait=wait2, done=done2)
         eventlet.sleep(0)
@@ -4447,7 +4451,7 @@ class LibvirtDriverTestCase(test.TestCase):
                       block_device_info=None):
             pass
 
-        def fake_create_domain(xml, inst_name=''):
+        def fake_create_domain(xml, instance=None):
             return None
 
         def fake_enable_hairpin(instance):
@@ -4493,7 +4497,7 @@ class LibvirtDriverTestCase(test.TestCase):
         def fake_plug_vifs(instance, network_info):
             pass
 
-        def fake_create_domain(xml, inst_name=''):
+        def fake_create_domain(xml, instance=None):
             return None
 
         def fake_enable_hairpin(instance):