From 03e005993262357eb955601fb8acef38654eadf8 Mon Sep 17 00:00:00 2001
From: Pierre Riteau <priteau@uchicago.edu>
Date: Fri, 11 Aug 2017 09:20:04 +0100
Subject: [PATCH] Allow update host API to add new extra capabilities

The update host API can only update existing extra capabilities.
However, we can support adding new extra capabilities to hosts without
API change.

With this patch, Blazar can both create and update extra capabilities
via the update host API.

Partial-Bug: #1674524
Change-Id: Ic9bd743a1c31858db9390a3379dc19e1e54327a8
---
 blazar/plugins/oshosts/host_plugin.py         | 26 +++++++++++++------
 .../plugins/test_physical_host_plugin.py      | 12 +++++++++
 ...ities-in-update-host-c74ce75c88e88c67.yaml |  7 +++++
 3 files changed, 37 insertions(+), 8 deletions(-)
 create mode 100644 releasenotes/notes/create-extra-capabilities-in-update-host-c74ce75c88e88c67.yaml

diff --git a/blazar/plugins/oshosts/host_plugin.py b/blazar/plugins/oshosts/host_plugin.py
index a001fea4..7fb516ce 100644
--- a/blazar/plugins/oshosts/host_plugin.py
+++ b/blazar/plugins/oshosts/host_plugin.py
@@ -296,8 +296,6 @@ class PhysicalHostPlugin(base.BasePlugin, nova.NovaClientWrapper):
                 return None
 
     def update_computehost(self, host_id, values):
-        # NOTE (sbauza): Only update existing extra capabilites, don't create
-        #  other ones
         if values:
             cant_update_extra_capability = []
             for value in values:
@@ -305,17 +303,29 @@ class PhysicalHostPlugin(base.BasePlugin, nova.NovaClientWrapper):
                     host_id,
                     value,
                 )
-                for raw_capability in capabilities:
-                    capability = {
+                if capabilities:
+                    for raw_capability in capabilities:
+                        capability = {
+                            'capability_name': value,
+                            'capability_value': values[value],
+                        }
+                        try:
+                            db_api.host_extra_capability_update(
+                                raw_capability['id'], capability)
+                        except (db_ex.BlazarDBException, RuntimeError):
+                            cant_update_extra_capability.append(
+                                raw_capability['capability_name'])
+                else:
+                    new_capability = {
+                        'computehost_id': host_id,
                         'capability_name': value,
                         'capability_value': values[value],
                     }
                     try:
-                        db_api.host_extra_capability_update(
-                            raw_capability['id'], capability)
-                    except RuntimeError:
+                        db_api.host_extra_capability_create(new_capability)
+                    except (db_ex.BlazarDBException, RuntimeError):
                         cant_update_extra_capability.append(
-                            raw_capability['capability_name'])
+                            new_capability['capability_name'])
             if cant_update_extra_capability:
                 raise manager_ex.CantAddExtraCapability(
                     host=host_id,
diff --git a/blazar/tests/plugins/test_physical_host_plugin.py b/blazar/tests/plugins/test_physical_host_plugin.py
index e1fda608..de71dbf4 100644
--- a/blazar/tests/plugins/test_physical_host_plugin.py
+++ b/blazar/tests/plugins/test_physical_host_plugin.py
@@ -267,6 +267,18 @@ class PhysicalHostPluginTestCase(tests.TestCase):
                           self.fake_phys_plugin.update_computehost,
                           self.fake_host_id, host_values)
 
+    def test_update_host_with_new_extra_capability(self):
+        host_values = {'buzz': 'word'}
+
+        self.db_host_extra_capability_get_all_per_name.return_value = []
+        self.fake_phys_plugin.update_computehost(self.fake_host_id,
+                                                 host_values)
+        self.db_host_extra_capability_create.assert_called_once_with({
+            'computehost_id': '1',
+            'capability_name': 'buzz',
+            'capability_value': 'word'
+        })
+
     def test_delete_host(self):
         self.fake_phys_plugin.delete_computehost(self.fake_host_id)
 
diff --git a/releasenotes/notes/create-extra-capabilities-in-update-host-c74ce75c88e88c67.yaml b/releasenotes/notes/create-extra-capabilities-in-update-host-c74ce75c88e88c67.yaml
new file mode 100644
index 00000000..af39548a
--- /dev/null
+++ b/releasenotes/notes/create-extra-capabilities-in-update-host-c74ce75c88e88c67.yaml
@@ -0,0 +1,7 @@
+---
+features:
+  - |
+    The update host API now allows new extra capabilities to be created on
+    existing hosts, in addition to allowing values of existing keys to be
+    modified. However, extra capabilities cannot yet be removed due to lack of
+    API support. As a workaround, operators can delete hosts and recreate them.