Placement client: ensure_resource_provider

All other API resources (ie. traits, resource_provider_traits and
resource_provider_inventories) we need to report on for minimum
guaranteed bandwidth have update methods that can be called in one go,
either because they have update-or-create or update-overrides-all
semantics. Here we add the 'ensure_resource_provider' method so
resource providers also have a similarly simple way of being kept in
sync.  We also add 'update_resource_provider' as a pre-requisite. On
the side we also fix a little, silent unit test type error.

Change-Id: Ib615ceeb323970d179ffb3dee14e52cb40e73ae7
Partial-Bug: #1578989
See-Also: https://review.openstack.org/502306 (nova spec)
See-Also: https://review.openstack.org/508149 (neutron spec)

neutron_lib/clients/placement.py

@@ -128,13 +128,56 @@ class PlacementAPIClient(object):
     def create_resource_provider(self, resource_provider):
         """Create a resource provider.
 
-        :param resource_provider: The resource provider. A dict with the name
-                                  (required) and the uuid (required).
+        :param resource_provider: The resource provider. A dict with
+                                  the uuid (required),
+                                  the name (required) and
+                                  the parent_provider_uuid (optional).
         :returns: The resource provider created.
         """
         url = '/resource_providers'
         return self._post(url, resource_provider).json()
 
+    @_check_placement_api_available
+    def update_resource_provider(self, resource_provider):
+        """Update the resource provider identified by uuid.
+
+        :param resource_provider: The resource provider. A dict with
+                                  the uuid (required),
+                                  the name (required) and
+                                  the parent_provider_uuid (optional).
+        :returns: The updated resource provider.
+        """
+        url = '/resource_providers/%s' % resource_provider['uuid']
+        # update does not tolerate if the uuid is repeated in the body
+        update_body = resource_provider.copy()
+        update_body.pop('uuid')
+        try:
+            return self._put(url, update_body).json()
+        except ks_exc.NotFound:
+            raise n_exc.PlacementResourceProviderNotFound(
+                resource_provider=resource_provider['uuid'])
+        except ks_exc.Conflict:
+            raise n_exc.PlacementResourceProviderNameNotUnique(
+                name=resource_provider['name'])
+
+    @_check_placement_api_available
+    def ensure_resource_provider(self, resource_provider):
+        """Ensure a resource provider exists by updating or creating it.
+
+        :param resource_provider: The resource provider. A dict with
+                                  the uuid (required),
+                                  the name (required) and
+                                  the parent_provider_uuid (optional).
+        :returns: The Resource Provider updated or created.
+
+        Beware, this is not an atomic operation of the API.
+        """
+        try:
+            return self.update_resource_provider(
+                resource_provider=resource_provider)
+        except n_exc.PlacementResourceProviderNotFound:
+            return self.create_resource_provider(resource_provider)
+
     @_check_placement_api_available
     def delete_resource_provider(self, resource_provider_uuid):
         """Delete a resource provider.

neutron_lib/exceptions/placement.py

@@ -60,3 +60,8 @@ class PlacementResourceClassNotFound(exceptions.NotFound):
 class PlacementAPIVersionIncorrect(exceptions.NotFound):
     message = _("Placement API version %(current_version)s, do not meet the"
                 "needed version %(needed_version)s.")
+
+
+class PlacementResourceProviderNameNotUnique(exceptions.Conflict):
+    message = _("Another resource provider exists with the provided name: "
+                "%(name)s.")

neutron_lib/tests/unit/clients/test_placement.py

@@ -24,6 +24,11 @@ from neutron_lib.tests import _base as base
 
 
 RESOURCE_PROVIDER_UUID = uuidutils.generate_uuid()
+RESOURCE_PROVIDER_NAME = 'resource_provider_name'
+RESOURCE_PROVIDER = {
+    'uuid': RESOURCE_PROVIDER_UUID,
+    'name': RESOURCE_PROVIDER_NAME,
+}
 RESOURCE_PROVIDER_GENERATION = 1
 RESOURCE_CLASS_NAME = 'resource_class_name'
 TRAIT_NAME = 'trait_name'
@@ -49,10 +54,38 @@ class TestPlacementAPIClient(base.BaseTestCase):
 
     def test_create_resource_provider(self):
         self.placement_api_client.create_resource_provider(
-            RESOURCE_PROVIDER_UUID)
+            RESOURCE_PROVIDER)
         self.placement_fixture.mock_post.assert_called_once_with(
             '/resource_providers',
-            RESOURCE_PROVIDER_UUID
+            RESOURCE_PROVIDER
+        )
+
+    def test_update_resource_provider(self):
+        self.placement_api_client.update_resource_provider(
+            RESOURCE_PROVIDER)
+        self.placement_fixture.mock_put.assert_called_once_with(
+            '/resource_providers/%s' % RESOURCE_PROVIDER_UUID,
+            {'name': RESOURCE_PROVIDER_NAME}
+        )
+
+    def test_ensure_update_resource_provider(self):
+        self.placement_api_client.ensure_resource_provider(
+            RESOURCE_PROVIDER)
+        self.placement_fixture.mock_put.assert_called_once_with(
+            '/resource_providers/%s' % RESOURCE_PROVIDER_UUID,
+            {'name': RESOURCE_PROVIDER_NAME}
+        )
+        self.placement_fixture.mock_post.assert_not_called()
+
+    def test_ensure_create_resource_provider(self):
+        self.placement_fixture.mock_put.side_effect = \
+            n_exc.PlacementResourceProviderNotFound(
+                resource_provider=RESOURCE_PROVIDER_UUID)
+        self.placement_api_client.ensure_resource_provider(
+            RESOURCE_PROVIDER)
+        self.placement_fixture.mock_post.assert_called_once_with(
+            '/resource_providers',
+            RESOURCE_PROVIDER
         )
 
     def test_delete_resource_provider(self):

releasenotes/notes/placement-client-update-ensure-rp-9e5c3cf34d49b212.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    New methods available in Placement client:
+    ``update_resource_provider`` and ``ensure_resource_provider``.