Fix VMwareVCDriver to support multi-datastore

This fixes the issue of VCDriver selecting the first datastore of
Cluster while provisioning instances. User can provide a regex to
match with the desired datastores.

Fixes: bug #1104994

(cherry picked from commit 9579ece)

Conflicts:

        etc/nova/nova.conf.sample
        nova/tests/test_vmwareapi.py
        nova/tests/test_vmwareapi_vm_util.py
        nova/virt/vmwareapi/driver.py
        nova/virt/vmwareapi/vm_util.py
        nova/virt/vmwareapi/vmops.py

Change-Id: I319b0d8afd03e9fef00ea0c8c799790714685104

nova/tests/test_vmwareapi.py

@@ -65,6 +65,7 @@ def setUp(self):
                    vmwareapi_host_password='test_pass',
                    vnc_enabled=False,
                    use_linked_clone=False)
+        self.flags(datastore_regex='.*', group='vmware')
         self.user_id = 'fake'
         self.project_id = 'fake'
         self.context = context.RequestContext(self.user_id, self.project_id)
@@ -447,3 +448,14 @@ def test_host_maintenance_on(self):
 
     def test_host_maintenance_off(self):
         self._test_host_action(self.conn.host_maintenance_mode, False)
+
+    def test_invalid_datastore_regex(self):
+        # Tests if we raise an exception for Invalid Regular Expression in
+        # vmware_datastore_regex
+        self.flags(vmwareapi_host_ip='test_url',
+                   vmwareapi_host_username='test_username',
+                   vmwareapi_host_password='test_pass',
+                   vnc_enabled=False,
+                   use_linked_clone=False)
+        self.flags(datastore_regex='fake-ds(01', group='vmware')
+        self.assertRaises(exception.InvalidInput, driver.VMwareVCDriver, None)

nova/tests/test_vmwareapi_vm_util.py

@@ -17,6 +17,7 @@
 #    under the License.
 
 import collections
+import re
 
 from nova import exception
 from nova import test
@@ -49,6 +50,46 @@ def test_get_datastore_ref_and_name(self):
         self.assertEquals(result[2], 1024 * 1024 * 1024 * 1024)
         self.assertEquals(result[3], 1024 * 1024 * 500 * 1024)
 
+    def test_get_datastore_ref_and_name_with_regex(self):
+        # Test with a regex that matches with a datastore
+        datastore_valid_regex = re.compile("^openstack.*\d$")
+        fake_objects = [fake.Datastore("openstack-ds0"),
+                        fake.Datastore("fake-ds0"),
+                        fake.Datastore("fake-ds1")]
+        result = vm_util.get_datastore_ref_and_name(
+            fake_session(fake_objects), None, None, datastore_valid_regex)
+        self.assertEquals("openstack-ds0", result[1])
+
+    def test_get_datastore_ref_and_name_with_list(self):
+        # Test with a regex containing whitelist of datastores
+        datastore_valid_regex = re.compile("(openstack-ds0|openstack-ds2)")
+        fake_objects = [fake.Datastore("openstack-ds0"),
+                        fake.Datastore("fake-ds0"),
+                        fake.Datastore("fake-ds1")]
+        result = vm_util.get_datastore_ref_and_name(
+            fake_session(fake_objects), None, None, datastore_valid_regex)
+        self.assertNotEquals("openstack-ds1", result[1])
+
+    def test_get_datastore_ref_and_name_with_regex_error(self):
+        # Test with a regex that has no match
+        # Checks if code raises DatastoreNotFound with a specific message
+        datastore_invalid_regex = re.compile("unknown-ds")
+        exp_message = (_("Datastore regex %s did not match any datastores")
+                       % datastore_invalid_regex.pattern)
+        fake_objects = [fake.Datastore("fake-ds0"),
+                        fake.Datastore("fake-ds1")]
+        # assertRaisesRegExp would have been a good choice instead of
+        # try/catch block, but it's available only from Py 2.7.
+        try:
+            vm_util.get_datastore_ref_and_name(
+                fake_session(fake_objects), None, None,
+                datastore_invalid_regex)
+        except exception.DatastoreNotFound as e:
+            self.assertEquals(exp_message, e.args[0])
+        else:
+            self.fail("DatastoreNotFound Exception was not raised with "
+                      "message: %s" % exp_message)
+
     def test_get_datastore_ref_and_name_without_datastore(self):
 
         self.assertRaises(exception.DatastoreNotFound,

nova/virt/vmwareapi/driver.py

@@ -37,6 +37,7 @@
 :use_linked_clone:          Whether to use linked clone (default: True)
 """
 
+import re
 import time
 
 from eventlet import event
@@ -107,8 +108,17 @@
                 help='Whether to use linked clone'),
     ]
 
+vmware_opts = [
+    cfg.StrOpt('datastore_regex',
+               default=None,
+               help='Regex to match the name of a datastore. '
+                    'Used only if compute_driver is '
+                    'vmwareapi.VMwareVCDriver.'),
+    ]
+
 CONF = cfg.CONF
 CONF.register_opts(vmwareapi_opts)
+CONF.register_opts(vmware_opts, 'vmware')
 
 TIME_BETWEEN_API_CALL_RETRIES = 2.0
 
@@ -359,6 +369,20 @@ def __init__(self, virtapi, read_only=False, scheme="https"):
             if self._cluster is None:
                 raise exception.NotFound(_("VMware Cluster %s is not found")
                                            % self._cluster_name)
+
+        self._datastore_regex = None
+        if CONF.vmware.datastore_regex:
+            try:
+                self._datastore_regex = re.compile(CONF.vmware.datastore_regex)
+            except re.error:
+                raise exception.InvalidInput(reason=
+                _("Invalid Regular Expression %s")
+                % CONF.vmware.datastore_regex)
+        self._volumeops = volumeops.VMwareVolumeOps(self._session,
+                                                    self._cluster_name)
+        self._vmops = vmops.VMwareVMOps(self._session, self.virtapi,
+                                        self._volumeops, self._cluster_name,
+                                        self._datastore_regex)
         self._vc_state = None
 
     @property

nova/virt/vmwareapi/fake.py

@@ -310,10 +310,10 @@ def __init__(self):
 class Datastore(ManagedObject):
     """Datastore class."""
 
-    def __init__(self):
+    def __init__(self, name="fake-ds"):
         super(Datastore, self).__init__("Datastore")
         self.set("summary.type", "VMFS")
-        self.set("summary.name", "fake-ds")
+        self.set("summary.name", name)
         self.set("summary.capacity", 1024 * 1024 * 1024 * 1024)
         self.set("summary.freeSpace", 500 * 1024 * 1024 * 1024)
 

nova/virt/vmwareapi/vm_util.py

@@ -656,7 +656,8 @@ def get_host_ref(session, cluster=None):
     return host_mor
 
 
-def get_datastore_ref_and_name(session, cluster=None, host=None):
+def get_datastore_ref_and_name(session, cluster=None, host=None,
+                               datastore_regex=None):
     """Get the datastore list and choose the first local storage."""
     if cluster is None and host is None:
         data_stores = session._call_method(vim_util, "get_objects",
@@ -698,6 +699,12 @@ def get_datastore_ref_and_name(session, cluster=None, host=None):
                 ds_free = prop.val
         # Local storage identifier
         if ds_type == "VMFS" or ds_type == "NFS":
-            return elem.obj, ds_name, ds_cap, ds_free
+            if not datastore_regex or datastore_regex.match(ds_name):
+                return elem.obj, ds_name, ds_cap, ds_free
 
+    if datastore_regex:
+        raise exception.DatastoreNotFound(
+                _("Datastore regex %s did not match any datastores")
+                % datastore_regex.pattern)
+    else:
         raise exception.DatastoreNotFound()

nova/virt/vmwareapi/vmops.py

@@ -74,7 +74,8 @@
 class VMwareVMOps(object):
     """Management class for VM-related tasks."""
 
-    def __init__(self, session, virtapi, volumeops, cluster_name=None):
+    def __init__(self, session, virtapi, volumeops, cluster_name=None,
+                 datastore_regex=None):
         """Initializer."""
         self.compute_api = compute.API()
         self._session = session
@@ -85,6 +86,7 @@ def __init__(self, session, virtapi, volumeops, cluster_name=None):
         else:
             self._cluster = vm_util.get_cluster_ref_from_name(
                                         self._session, cluster_name)
+        self._datastore_regex = datastore_regex
         self._instance_path_base = VMWARE_PREFIX + CONF.base_dir_name
         self._default_root_device = 'vda'
         self._rescue_suffix = '-rescue'
@@ -136,7 +138,8 @@ def spawn(self, context, instance, image_meta, network_info,
 
         client_factory = self._session._get_vim().client.factory
         service_content = self._session._get_vim().get_service_content()
-        ds = vm_util.get_datastore_ref_and_name(self._session, self._cluster)
+        ds = vm_util.get_datastore_ref_and_name(self._session, self._cluster,
+                 datastore_regex=self._datastore_regex)
         data_store_ref = ds[0]
         data_store_name = ds[1]