Support 'alive' filter for get_agents() in agents_db

Presently 'alive' filter is not supported when the
neutron cli calls 'neutron agent_list --alive False'.

This patch fixes the issue by pruning the agent list
according to the 'alive' filter. If the client passes
invalid value to the alive filter, then InvalidInput
exception is raised.

DocImpact
APIImpact

Change-Id: I8935c09d82f6e88252560a5232adf22002cbae08
Closes-bug: #1398398

diff --git a/neutron/db/agents_db.py b/neutron/db/agents_db.py
index 2516886a42583cedf70e26bb954db9f940272cb9..ad309be87c5a31c72ee859178f3a3847d6354786 100644 (file)
--- a/neutron/db/agents_db.py
+++ b/neutron/db/agents_db.py
@@ -25,6 +25,7 @@ import sqlalchemy as sa
 from sqlalchemy.orm import exc
 from sqlalchemy import sql
 
+from neutron.api.v2 import attributes
 from neutron.db import model_base
 from neutron.db import models_v2
 from neutron.extensions import agent as ext_agent
@@ -143,9 +144,15 @@ class AgentDbMixin(ext_agent.AgentPluginBase):
         return query.all()
 
     def get_agents(self, context, filters=None, fields=None):
-        return self._get_collection(context, Agent,
-                                    self._make_agent_dict,
-                                    filters=filters, fields=fields)
+        agents = self._get_collection(context, Agent,
+                                      self._make_agent_dict,
+                                      filters=filters, fields=fields)
+        alive = filters and filters.get('alive', None)
+        if alive:
+            # alive filter will be a list
+            alive = attributes.convert_to_boolean(alive[0])
+            agents = [agent for agent in agents if agent['alive'] == alive]
+        return agents
 
     def _get_agent_by_type_and_host(self, context, agent_type, host):
         query = self._model_query(context, Agent)

diff --git a/neutron/tests/unit/db/test_agent_db.py b/neutron/tests/unit/db/test_agent_db.py
index b0a1daef35bc7e17995590f54d0c602345013afe..e46665fb1e9f854f2b27237f192b9540c6e81b4d 100644 (file)
--- a/neutron/tests/unit/db/test_agent_db.py
+++ b/neutron/tests/unit/db/test_agent_db.py
@@ -13,28 +13,73 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import datetime
 import mock
+
 from oslo.db import exception as exc
 from oslo.utils import timeutils
+import testscenarios
 
 from neutron.common import constants
+from neutron.common import exceptions as n_exc
 from neutron import context
 from neutron.db import agents_db
 from neutron.db import db_base_plugin_v2 as base_plugin
 from neutron.tests.unit import testlib_api
 
+# the below code is required for the following reason
+# (as documented in testscenarios)
+"""Multiply tests depending on their 'scenarios' attribute.
+
+    This can be assigned to 'load_tests' in any test module to make this
+    automatically work across tests in the module.
+"""
+load_tests = testscenarios.load_tests_apply_scenarios
+
 
 class FakePlugin(base_plugin.NeutronDbPluginV2, agents_db.AgentDbMixin):
     """A fake plugin class containing all DB methods."""
 
 
-class TestAgentsDbMixin(testlib_api.SqlTestCase):
+class TestAgentsDbBase(testlib_api.SqlTestCase):
     def setUp(self):
-        super(TestAgentsDbMixin, self).setUp()
-
+        super(TestAgentsDbBase, self).setUp()
         self.context = context.get_admin_context()
         self.plugin = FakePlugin()
 
+    def _get_agents(self, hosts, agent_type):
+        return [
+            agents_db.Agent(
+                binary='foo-agent',
+                host=host,
+                agent_type=agent_type,
+                topic='foo_topic',
+                configurations="",
+                created_at=timeutils.utcnow(),
+                started_at=timeutils.utcnow(),
+                heartbeat_timestamp=timeutils.utcnow())
+            for host in hosts
+        ]
+
+    def _save_agents(self, agents):
+        for agent in agents:
+            with self.context.session.begin(subtransactions=True):
+                self.context.session.add(agent)
+
+    def _create_and_save_agents(self, hosts, agent_type, down_agents_count=0):
+        agents = self._get_agents(hosts, agent_type)
+        # bring down the specified agents
+        for agent in agents[:down_agents_count]:
+            agent['heartbeat_timestamp'] -= datetime.timedelta(minutes=60)
+
+        self._save_agents(agents)
+        return agents
+
+
+class TestAgentsDbMixin(TestAgentsDbBase):
+    def setUp(self):
+        super(TestAgentsDbMixin, self).setUp()
+
         self.agent_status = {
             'agent_type': 'Open vSwitch agent',
             'binary': 'neutron-openvswitch-agent',
@@ -42,27 +87,12 @@ class TestAgentsDbMixin(testlib_api.SqlTestCase):
             'topic': 'N/A'
         }
 
-    def _add_agent(self, agent_id, agent_type, agent_host):
-        with self.context.session.begin(subtransactions=True):
-            now = timeutils.utcnow()
-            agent = agents_db.Agent(id=agent_id,
-                                    agent_type=agent_type,
-                                    binary='foo_binary',
-                                    topic='foo_topic',
-                                    host=agent_host,
-                                    created_at=now,
-                                    started_at=now,
-                                    admin_state_up=True,
-                                    heartbeat_timestamp=now,
-                                    configurations='')
-            self.context.session.add(agent)
-            return agent
-
     def test_get_enabled_agent_on_host_found(self):
-        agent = self._add_agent('foo_id', constants.AGENT_TYPE_L3, 'foo_host')
+        agents = self._create_and_save_agents(['foo_host'],
+                                              constants.AGENT_TYPE_L3)
         expected = self.plugin.get_enabled_agent_on_host(
             self.context, constants.AGENT_TYPE_L3, 'foo_host')
-        self.assertEqual(expected, agent)
+        self.assertEqual(expected, agents[0])
 
     def test_get_enabled_agent_on_host_not_found(self):
         with mock.patch.object(agents_db.LOG, 'debug') as mock_log:
@@ -111,3 +141,56 @@ class TestAgentsDbMixin(testlib_api.SqlTestCase):
 
             self.assertEqual(add_mock.call_count, 2,
                              "Agent entry creation hasn't been retried")
+
+
+class TestAgentsDbGetAgents(TestAgentsDbBase):
+    scenarios = [
+        ('Get all agents', dict(agents=5, down_agents=2,
+                                agents_alive=None,
+                                expected_agents=5)),
+
+        ('Get alive agents (True)', dict(agents=5, down_agents=2,
+                                         agents_alive='True',
+                                         expected_agents=3)),
+
+        ('Get down agents (False)', dict(agents=5, down_agents=2,
+                                         agents_alive='False',
+                                         expected_agents=2)),
+
+        ('Get alive agents (true)', dict(agents=5, down_agents=2,
+                                         agents_alive='true',
+                                         expected_agents=3)),
+
+        ('Get down agents (false)', dict(agents=5, down_agents=2,
+                                         agents_alive='false',
+                                         expected_agents=2)),
+
+        ('Get agents invalid alive filter', dict(agents=5, down_agents=2,
+                                                 agents_alive='invalid',
+                                                 expected_agents=None)),
+    ]
+
+    def setUp(self):
+        # ensure that the first scenario will execute with nosetests
+        if not hasattr(self, 'agents'):
+            self.__dict__.update(self.scenarios[0][1])
+        super(TestAgentsDbGetAgents, self).setUp()
+
+    def test_get_agents(self):
+        hosts = ['host-%s' % i for i in range(self.agents)]
+        self._create_and_save_agents(hosts, constants.AGENT_TYPE_L3,
+                                     down_agents_count=self.down_agents)
+        if self.agents_alive == 'invalid':
+            self.assertRaises(n_exc.InvalidInput, self.plugin.get_agents,
+                              self.context,
+                              filters={'alive': [self.agents_alive]})
+        else:
+            returned_agents = self.plugin.get_agents(
+                self.context, filters={'alive': [self.agents_alive]}
+                if self.agents_alive else None)
+            self.assertEqual(self.expected_agents, len(returned_agents))
+            if self.agents_alive:
+                alive = (self.agents_alive == 'True' or
+                         self.agents_alive == 'true')
+                for agent in returned_agents:
+                    self.assertEqual(alive, agent['alive'])