Update get_hosts to use available API

os-hosts was deprecated in nova quite some time ago.  This patch updates
get_hosts to use the available os-hypervisors functions.

Change-Id: I36421e9859a266f0278c1b5f2acb4ebbacbfca82
Story: 2006584
Task: 36708
bz: 1740567
(cherry picked from commit aab68ced6a84c9fa39adb2cb9bb19165e699ff3a)

2 files changed, 22 insertions, 30 deletions

diff --git a/heat/engine/clients/os/nova.py b/heat/engine/clients/os/nova.py
index c0f280bbf..e4b9e4904 100644
--- a/heat/engine/clients/os/nova.py
+++ b/heat/engine/clients/os/nova.py
@@ -281,20 +281,15 @@ class NovaClientPlugin(microversion_mixin.MicroversionMixin,
 
         return flavor
 
-    def get_host(self, host_name):
-        """Get the host id specified by name.
+    def get_host(self, hypervisor_hostname):
+        """Gets list of matching hypervisors by specified name.
 
-        :param host_name: the name of host to find
-        :returns: the list of match hosts
-        :raises exception.EntityNotFound:
+        :param hypervisor_hostname: the name of host to find
+        :returns: list of matching hypervisor hosts
+        :raises nova client exceptions.NotFound:
         """
 
-        host_list = self.client().hosts.list()
-        for host in host_list:
-            if host.host_name == host_name and host.service == self.COMPUTE:
-                return host
-
-        raise exception.EntityNotFound(entity='Host', name=host_name)
+        return self.client().hypervisors.search(hypervisor_hostname)
 
     def get_keypair(self, key_name):
         """Get the public key specified by :key_name:
@@ -872,4 +867,6 @@ class FlavorConstraint(NovaBaseConstraint):
 
 class HostConstraint(NovaBaseConstraint):
 
+    expected_exceptions = (exceptions.NotFound,)
+
     resource_getter_name = 'get_host'
diff --git a/heat/tests/clients/test_nova_client.py b/heat/tests/clients/test_nova_client.py
index 35e37cc61..e78f82667 100644
--- a/heat/tests/clients/test_nova_client.py
+++ b/heat/tests/clients/test_nova_client.py
@@ -118,28 +118,21 @@ class NovaClientPluginTest(NovaClientPluginTestCase):
 
     def test_get_host(self):
         """Tests the get_host function."""
-        my_host_name = 'myhost'
+        my_hypervisor_hostname = 'myhost'
         my_host = mock.MagicMock()
-        my_host.host_name = my_host_name
-        my_host.service = 'compute'
-
-        wrong_host = mock.MagicMock()
-        wrong_host.host_name = 'wrong_host'
-        wrong_host.service = 'compute'
-        self.nova_client.hosts.list.side_effect = [
-            [my_host],
-            [wrong_host],
-            exception.EntityNotFound(entity='Host', name='nohost')
+        my_host.hypervisor_hostname = my_hypervisor_hostname
+
+        self.nova_client.hypervisors.search.side_effect = [
+            my_host, nova_exceptions.NotFound(404)
         ]
-        self.assertEqual(my_host, self.nova_plugin.get_host(my_host_name))
-        self.assertRaises(exception.EntityNotFound,
-                          self.nova_plugin.get_host, my_host_name)
-        self.assertRaises(exception.EntityNotFound,
+        self.assertEqual(my_host,
+                         self.nova_plugin.get_host(my_hypervisor_hostname))
+        self.assertRaises(nova_exceptions.NotFound,
                           self.nova_plugin.get_host, 'nohost')
-        self.assertEqual(3, self.nova_client.hosts.list.call_count)
-        calls = [mock.call(), mock.call(), mock.call()]
+        self.assertEqual(2, self.nova_client.hypervisors.search.call_count)
+        calls = [mock.call('myhost'), mock.call('nohost')]
         self.assertEqual(calls,
-                         self.nova_client.hosts.list.call_args_list)
+                         self.nova_client.hypervisors.search.call_args_list)
 
     def test_get_keypair(self):
         """Tests the get_keypair function."""
@@ -558,7 +551,9 @@ class HostConstraintTest(common.HeatTestCase):
     def test_validation_error(self):
         self.mock_get_host.side_effect = exception.EntityNotFound(
             entity='Host', name='bar')
-        self.assertFalse(self.constraint.validate("bar", self.ctx))
+        self.assertRaises(
+            exception.EntityNotFound,
+            self.constraint.validate, "bar", self.ctx)
 
 
 class KeypairConstraintTest(common.HeatTestCase):