Make get_capabilities look for clusters

Currently get_capabilities accepts only host as a service identifier and
fails when it cannot find a service with such host property. In A/A
deployment, it should accept cluster_name as well, because
get_capabilities addresses backend and not individual host. This commit
fixes this up by making the call seek for available services using both
host and cluster_name properties.

Although it's an API change, it doesn't need a new microversion, because
it falls under "Did we silently fail to do what is asked?" category.

Change-Id: If7bca131c84fc997da8ad277eccd134e8ca4b316
Closes-Bug: 1660990

cinder/api/contrib/capabilities.py

@@ -44,16 +44,18 @@ class CapabilitiesController(wsgi.Controller):
         """Return capabilities list of given backend."""
         context = req.environ['cinder.context']
         authorize(context, 'capabilities')
-        filters = {'host': id, 'binary': 'cinder-volume'}
-        service = objects.ServiceList.get_all(context, filters)
-        if not service:
+        filters = {'host_or_cluster': id, 'binary': 'cinder-volume'}
+        services = objects.ServiceList.get_all(context, filters)
+        if not services:
             msg = (_("Can't find service: %s") % id)
             raise exception.NotFound(msg)
+        topic = services[0].service_topic_queue
         try:
-            capabilities = self.volume_api.get_capabilities(context, id, False)
+            capabilities = self.volume_api.get_capabilities(context, topic,
+                                                            False)
         except oslo_messaging.MessagingTimeout:
-            raise exception.RPCTimeout(service=id)
-        return self._view_builder.summary(req, capabilities, id)
+            raise exception.RPCTimeout(service=topic)
+        return self._view_builder.summary(req, capabilities, topic)
 
 
 class Capabilities(extensions.ExtensionDescriptor):

cinder/db/api.py

@@ -117,7 +117,9 @@ def service_get(context, service_id=None, backend_match_level=None, **filters):
 def service_get_all(context, backend_match_level=None, **filters):
     """Get all services that match the criteria.
 
-    A possible filter is is_up=True and it will filter nodes that are down.
+    A possible filter is is_up=True and it will filter nodes that are down,
+    as well as host_or_cluster, that lets you look for services using both
+    of these properties.
 
     :param filters: Filters for the query in the form of key/value arguments.
     :param backend_match_level: 'pool', 'backend', or 'host' for host and

cinder/db/sqlalchemy/api.py

@@ -449,8 +449,9 @@ def _clustered_bool_field_filter(query, field_name, filter_value):
 
 
 def _service_query(context, session=None, read_deleted='no', host=None,
-                   cluster_name=None, is_up=None, backend_match_level=None,
-                   disabled=None, frozen=None, **filters):
+                   cluster_name=None, is_up=None, host_or_cluster=None,
+                   backend_match_level=None, disabled=None, frozen=None,
+                   **filters):
     filters = _clean_filters(filters)
     if filters and not is_valid_model_filters(models.Service, filters):
         return None
@@ -467,6 +468,13 @@ def _service_query(context, session=None, read_deleted='no', host=None,
     if cluster_name:
         query = query.filter(_filter_host(models.Service.cluster_name,
                                           cluster_name, backend_match_level))
+    if host_or_cluster:
+        query = query.filter(or_(
+            _filter_host(models.Service.host, host_or_cluster,
+                         backend_match_level),
+            _filter_host(models.Service.cluster_name, host_or_cluster,
+                         backend_match_level),
+        ))
 
     query = _clustered_bool_field_filter(query, 'disabled', disabled)
     query = _clustered_bool_field_filter(query, 'frozen', frozen)

cinder/tests/unit/api/contrib/test_capabilities.py

@@ -70,13 +70,13 @@ class CapabilitiesAPITest(test.TestCase):
     @mock.patch('cinder.volume.rpcapi.VolumeAPI.get_capabilities',
                 rpcapi_get_capabilities)
     def test_capabilities_summary(self, mock_services):
-        mock_services.return_value = [{'name': 'fake'}]
+        mock_services.return_value = [{'name': 'fake', 'host': 'fake_host'}]
         req = fakes.HTTPRequest.blank('/fake/capabilities/fake')
         req.environ['cinder.context'] = self.ctxt
         res = self.controller.show(req, 'fake')
 
         expected = {
-            'namespace': 'OS::Storage::Capabilities::fake',
+            'namespace': 'OS::Storage::Capabilities::fake_host',
             'vendor_name': 'OpenStack',
             'volume_backend_name': 'lvm',
             'pool_name': 'pool',

cinder/tests/unit/test_db_api.py

@@ -277,6 +277,18 @@ class DBAPIServiceTestCase(BaseTest):
         real = db.service_get_all(self.ctxt, cluster_name='cluster')
         self._assertEqualListsOfObjects(expected, real)
 
+    def test_service_get_all_by_host_or_cluster(self):
+        values = [
+            {'host': 'host1', 'cluster_name': 'cluster'},
+            {'host': 'host2', 'cluster_name': 'host1'},
+            {'host': 'host3', 'cluster_name': 'cluster@backend'},
+            {'host': 'host4', 'cluster_name': 'cluster2'},
+        ]
+        services = [utils.create_service(self.ctxt, vals) for vals in values]
+        expected = services[0:2]
+        real = db.service_get_all(self.ctxt, host_or_cluster='host1')
+        self._assertEqualListsOfObjects(expected, real)
+
     def test_service_get_by_args_not_found_exception(self):
         self.assertRaises(exception.ServiceNotFound,
                           db.service_get,