Fix host manager node detection logic

This is the last in a series of patches to prepare Ironic for the
removal of capabilities in Nova HostManager.

IronicHostManager used to rely on capabilities info to decide which
host state class to use, VM or baremetal. This has been broken since
host capabilities reporting were removed in Nova, resulting in Nova
HostState class always being used.

This patch fixes the detection logic in IronicHostManager to correctly
choose IronicHostState class for use with baremetal nodes. Tests are
added to verify that the correct class is used for both vm and
baremetal nodes.

In reality, the new detection logic will not start to deliver the
correct HostState class until the Nova HostManager change has landed.

Change-Id: Ifa47d721835cfea87e9d0bce87c7853dd6724b98
Closes-Bug: #1260265

ironic/nova/scheduler/ironic_host_manager.py

@@ -84,18 +84,17 @@ class IronicNodeState(host_manager.HostState):
         self.updated = timeutils.utcnow()
 
 
-def new_host_state(self, host, node, capabilities=None, service=None):
+def new_host_state(self, host, node, **kwargs):
     """Returns an instance of IronicNodeState or HostState according to
-    capabilities. If 'ironic_driver' is in capabilities, it returns an
-    instance of IronicHostState. If not, returns an instance of HostState.
+    compute['cpu_info']. If 'cpu_info' equals 'baremetal cpu', it returns an
+    instance of IronicNodeState. If not, returns an instance of HostState.
     """
-    if capabilities is None:
-        capabilities = {}
-    cap = capabilities.get('compute', {})
-    if bool(cap.get('ironic_driver')):
-        return IronicNodeState(host, node, capabilities, service)
+    compute = kwargs.get('compute')
+
+    if compute and compute.get('cpu_info') == 'baremetal cpu':
+        return IronicNodeState(host, node, **kwargs)
     else:
-        return host_manager.HostState(host, node, capabilities, service)
+        return host_manager.HostState(host, node, **kwargs)
 
 
 class IronicHostManager(host_manager.HostManager):

ironic/nova/tests/scheduler/test_ironic_host_manager.py

@@ -17,6 +17,8 @@
 Tests For IronicHostManager
 """
 
+import mock
+
 from ironic.nova.scheduler import ironic_host_manager
 from ironic.nova.tests.scheduler import ironic_fakes
 
@@ -24,6 +26,7 @@ from nova import db
 from nova import exception
 from nova.openstack.common import jsonutils
 from nova.scheduler import filters
+from nova.scheduler import host_manager
 from nova import test
 
 
@@ -87,6 +90,22 @@ class IronicHostManagerChangedNodesTestCase(test.NoDBTestCase):
                                         '[["i386", "baremetal", "baremetal"]]',
                             free_disk_gb=10, free_ram_mb=1024)
 
+    @mock.patch.object(ironic_host_manager.IronicNodeState, '__init__')
+    def test_create_ironic_node_state(self, init_mock):
+        init_mock.return_value = None
+        compute = {'cpu_info': 'baremetal cpu'}
+        host_state = self.host_manager.host_state_cls('fake-host', 'fake-node',
+                                                      compute=compute)
+        self.assertIs(ironic_host_manager.IronicNodeState, type(host_state))
+
+    @mock.patch.object(host_manager.HostState, '__init__')
+    def test_create_non_ironic_host_state(self, init_mock):
+        init_mock.return_value = None
+        compute = {'cpu_info': 'other cpu'}
+        host_state = self.host_manager.host_state_cls('fake-host', 'fake-node',
+                                                      compute=compute)
+        self.assertIs(host_manager.HostState, type(host_state))
+
     def test_get_all_host_states_after_delete_one(self):
         context = 'fake_context'