Fix nits in support traits changes

Addresses the comments from earlier patches:

https://review.openstack.org/535642

https://review.openstack.org/536085

Co-Authored-By: Matt Riedemann <mriedem.os@gmail.com>

Change-Id: I366b97ef3c141834f48949700edb968a7c7c4167

nova/api/openstack/placement/handlers/allocation_candidate.py

@@ -196,7 +196,7 @@ def _transform_allocation_candidates(alloc_cands, want_version):
 
     include_traits = want_version.matches((1, 17))
     p_sums = _transform_provider_summaries(alloc_cands.provider_summaries,
-                                           include_traits)
+                                           include_traits=include_traits)
     return {
         'allocation_requests': a_reqs,
         'provider_summaries': p_sums,

nova/api/openstack/placement/util.py

@@ -306,9 +306,9 @@ def normalize_traits_qs_param(val):
     """
     ret = set(substr.strip() for substr in val.split(','))
     if not all(trait for trait in ret):
-        msg = _('Invalid query string parameters: Expected \'required\' '
+        msg = _("Invalid query string parameters: Expected 'required' "
-                'parameter value of the form: HW_CPU_X86_VMX,CUSTOM_MAGIC. '
+                "parameter value of the form: HW_CPU_X86_VMX,CUSTOM_MAGIC. "
-                'Got: "%s"') % val
+                "Got: %s") % val
         raise webob.exc.HTTPBadRequest(msg)
     return ret
 

nova/cmd/status.py

@@ -196,9 +196,8 @@ class UpgradeCommands(object):
             versions = self._placement_get("/")
             max_version = pkg_resources.parse_version(
                 versions["versions"][0]["max_version"])
-            # NOTE(mriedem): 1.14 is required by nova-compute services to
+            # NOTE(mriedem): 1.17 is required by nova-scheduler to get
-            # get and set parent resource provider UUIDs for nested resource
+            # allocation candidates with required traits from the flavor.
-            # provider support.
             # NOTE: If you bump this version, remember to update the history
             # section in the nova-status man page (doc/source/cli/nova-status).
             needs_version = pkg_resources.parse_version("1.17")

nova/exception.py

@@ -2216,7 +2216,7 @@ class PowerVMAPIFailed(NovaException):
 
 
 class TraitNotFound(NotFound):
-    msg_fmt = _("No such trait(s): %(name)s.")
+    msg_fmt = _("No such trait(s): %(names)s.")
 
 
 class TraitExists(NovaException):

nova/objects/resource_provider.py

@@ -2481,7 +2481,7 @@ class Trait(base.NovaObject, base.NovaTimestampObject):
         result = context.session.query(models.Trait).filter_by(
             name=name).first()
         if not result:
-            raise exception.TraitNotFound(name=name)
+            raise exception.TraitNotFound(names=name)
         return result
 
     @classmethod
@@ -2500,7 +2500,7 @@ class Trait(base.NovaObject, base.NovaTimestampObject):
         res = context.session.query(models.Trait).filter_by(
             name=name).delete()
         if not res:
-            raise exception.TraitNotFound(name=name)
+            raise exception.TraitNotFound(names=name)
 
     def destroy(self):
         if 'name' not in self:
@@ -3515,7 +3515,7 @@ class AllocationCandidates(base.NovaObject):
             # Double-check that we found a trait ID for each requested name
             if len(trait_map) != len(traits):
                 missing = traits - set(trait_map)
-                raise exception.TraitNotFound(name=', '.join(missing))
+                raise exception.TraitNotFound(names=', '.join(missing))
 
         # Contains a set of resource provider IDs that share some inventory for
         # each resource class requested. We do this here as an optimization. If

nova/scheduler/client/report.py

@@ -311,8 +311,8 @@ class SchedulerReportClient(object):
         the requested resource constraints.
 
         The provider summaries is a dict, keyed by resource provider UUID, of
-        inventory and capacity information for any resource provider involved
+        inventory and capacity information and traits for any resource
-        in the allocation_requests.
+        provider involved in the allocation_requests.
 
         :returns: A tuple with a list of allocation_request dicts, a dict of
                   provider information, and the microversion used to request
@@ -347,13 +347,20 @@ class SchedulerReportClient(object):
             return (data['allocation_requests'], data['provider_summaries'],
                     version)
 
-        msg = ("Failed to retrieve allocation candidates from placement API "
-               "for filters %(resources)s. Got %(status_code)d: %(err_text)s.")
         args = {
             'resources': res,
             'status_code': resp.status_code,
             'err_text': resp.text,
         }
+        if required_traits:
+            msg = ("Failed to retrieve allocation candidates from placement "
+                   "API for filters %(resources)s and traits %(traits)s. Got "
+                   "%(status_code)d: %(err_text)s.")
+            args['traits'] = qs_params['required']
+        else:
+            msg = ("Failed to retrieve allocation candidates from placement "
+                   "API for filters %(resources)s. Got %(status_code)d: "
+                   "%(err_text)s.")
         LOG.error(msg, args)
         return None, None, None
 

placement-api-ref/source/parameters.yaml

@@ -56,7 +56,7 @@ allocation_candidates_required:
   required: false
   min_version: 1.17
   description: >
-    Accepts a list of traits separated by `,`. Allocation requests in the
+    Accepts a list of comma-separated traits. Allocation requests in the
     response will be for resource providers that have capacity for all
     requested resources and the set of those resource providers will
     *collectively* contain all of the required traits.
@@ -252,7 +252,8 @@ provider_summaries:
   description: >
     A dictionary keyed by resource provider UUID,
     of dictionaries of inventory/capacity information. The list of traits
-    the resource provider has associated with it is included in version `1.17`.
+    the resource provider has associated with it is included in version `1.17`
+    and above.
 reserved: &reserved
   type: integer
   in: body

releasenotes/notes/allocation-candidates-traits-1adf079ed0c6563c.yaml

@@ -6,5 +6,5 @@ features:
     separated by ``,``, which is used to further limit the list of allocation
     requests to resource providers that have the capacity to fulfill the
     requested resources AND *collectively* have all of the required traits
-    associated with them. In the same microversion, the candidate attached
+    associated with them. In the same microversion, the provider summary
-    traits returned in the provider summary.
+    includes the traits associated with each provider.

releasenotes/notes/request-traits-in-nova-ffcb00f76229b6e9.yaml

@@ -1,14 +1,21 @@
 ---
 features:
   - |
-    Add traits support to the Nova. The new flavor extra spec is added to
+    Added traits support to the scheduler. A new flavor extra spec is added to
     support specifying the required traits. The syntax of extra spec is
-    as below:
+    ``trait:<trait_name>=required``, for example:
 
     - trait:HW_CPU_X86_AVX2=required
     - trait:STORAGE_DISK_SSD=required
 
-    The scheduler will pass traits to the GET /allocation_candidates endpoint
+    The scheduler will pass required traits to the
-    in the Placement API to filter out resource providers with each of the
+    ``GET /allocation_candidates`` endpoint in the Placement API to include
-    required traits. Currently the only valid value is required. For any other
+    only resource providers that can satisfy the required traits. Currently
-    value will be considered as invalid.
+    the only valid value is ``required``. Any other value will be considered
+    invalid.
+
+    This requires that the Placement API version 1.17 is available before
+    the ``nova-scheduler`` service can use this feature.
+
+    The FilterScheduler is currently the only scheduler driver that supports
+    this feature.