Run nova manage cell_v2 discover_host after ironic nodes are registered

Once cell_v2 is enabled by default in Ocata we will need to run this command
to update the host mappings whenever a new host is added.

Change-Id: I0bb98bfcf0c271ae3b577ca126dd3dfdaece179e
Depends-On: I591b451197dc3bd0783978f5e3d2b1c830afe54e
Related-Bug: #1649341

releasenotes/notes/discover_hosts-f1733234ba32a909.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    Run ``nova-manage cell_v2 discover_hosts`` when any baremetal nodes are
+    registered with the undercloud.

sudoers

@@ -4,4 +4,5 @@ Defaults:mistral !requiretty
 mistral ALL = (validations) NOPASSWD:SETENV: /usr/bin/run-validation
 mistral ALL = NOPASSWD: /usr/bin/chown validations\: /tmp/validations_identity_*
 mistral ALL = NOPASSWD: /usr/bin/rm -f /tmp/validations_identity_*
+mistral ALL = NOPASSWD: /bin/nova-manage cell_v2 discover_hosts
 validations ALL = NOPASSWD: ALL

tripleo_common/tests/utils/test_nodes.py

@@ -190,7 +190,8 @@ class NodesTest(base.TestCase):
                 'pm_password': 'random', 'pm_type': 'pxe_ssh', 'name': 'node1',
                 'capabilities': 'num_nics:6'}
 
-    def test_register_all_nodes_ironic_no_hw_stats(self):
+    @mock.patch('tripleo_common.utils.nodes.run_nova_cell_v2_discovery')
+    def test_register_all_nodes_ironic_no_hw_stats(self, mock_discovery):
         node_list = [self._get_node()]
 
         # Remove the hardware stats from the node dictionary
@@ -218,8 +219,10 @@ class NodesTest(base.TestCase):
                               address='aaa')
         ironic.node.create.assert_has_calls([pxe_node, mock.ANY])
         ironic.port.create.assert_has_calls([port_call])
+        mock_discovery.assert_called_once()
 
-    def test_register_all_nodes(self):
+    @mock.patch('tripleo_common.utils.nodes.run_nova_cell_v2_discovery')
+    def test_register_all_nodes(self, mock_discovery):
         node_list = [self._get_node()]
         node_properties = {"cpus": "1",
                            "memory_mb": "2048",
@@ -240,8 +243,10 @@ class NodesTest(base.TestCase):
                               address='aaa')
         ironic.node.create.assert_has_calls([pxe_node, mock.ANY])
         ironic.port.create.assert_has_calls([port_call])
+        mock_discovery.assert_called_once()
 
-    def test_register_all_nodes_kernel_ramdisk(self):
+    @mock.patch('tripleo_common.utils.nodes.run_nova_cell_v2_discovery')
+    def test_register_all_nodes_kernel_ramdisk(self, mock_discovery):
         node_list = [self._get_node()]
         node_properties = {"cpus": "1",
                            "memory_mb": "2048",
@@ -270,8 +275,10 @@ class NodesTest(base.TestCase):
                               address='aaa')
         ironic.node.create.assert_has_calls([pxe_node, mock.ANY])
         ironic.port.create.assert_has_calls([port_call])
+        mock_discovery.assert_called_once()
 
-    def test_register_all_nodes_uuid(self):
+    @mock.patch('tripleo_common.utils.nodes.run_nova_cell_v2_discovery')
+    def test_register_all_nodes_uuid(self, mock_discovery):
         node_list = [self._get_node()]
         node_list[0]['uuid'] = 'abcdef'
         node_properties = {"cpus": "1",
@@ -294,8 +301,10 @@ class NodesTest(base.TestCase):
                               address='aaa')
         ironic.node.create.assert_has_calls([pxe_node, mock.ANY])
         ironic.port.create.assert_has_calls([port_call])
+        mock_discovery.assert_called_once()
 
-    def test_register_all_nodes_caps_dict(self):
+    @mock.patch('tripleo_common.utils.nodes.run_nova_cell_v2_discovery')
+    def test_register_all_nodes_caps_dict(self, mock_discovery):
         node_list = [self._get_node()]
         node_list[0]['capabilities'] = {
             'num_nics': 7
@@ -319,6 +328,7 @@ class NodesTest(base.TestCase):
                               address='aaa')
         ironic.node.create.assert_has_calls([pxe_node, mock.ANY])
         ironic.port.create.assert_has_calls([port_call])
+        mock_discovery.assert_called_once()
 
     def test_register_update(self):
         node = self._get_node()

tripleo_common/utils/nodes.py

@@ -18,6 +18,7 @@ import re
 
 import six
 
+from oslo_concurrency import processutils
 from tripleo_common import exception
 from tripleo_common.utils import glance
 
@@ -381,6 +382,7 @@ def register_all_nodes(nodes_list, client, remove=False, glance_client=None,
         seen.append(node)
 
     _clean_up_extra_nodes(seen, client, remove=remove)
+    run_nova_cell_v2_discovery()
 
     return seen
 
@@ -443,3 +445,12 @@ def generate_hostmap(baremetal_client, compute_client):
             hostmap[port.address] = {"compute_name": node.name,
                                      "baremetal_name": bm_node.name}
     return hostmap
+
+
+def run_nova_cell_v2_discovery():
+    return processutils.execute(
+        '/usr/bin/sudo',
+        '/bin/nova-manage',
+        'cell_v2',
+        'discover_hosts'
+    )