Change to use WARNING level for heartbeat conflict errors

It's normal that ironic returns 409 Conflict from time to time, so
it's a bit confusing that we report this with Exception level and
traceback.

Change-Id: I1627c61facc3fadd0f5d9d324150e7d2833c7fbc
Closes-Bug: #1533113

ironic_python_agent/agent.py

@@ -118,6 +118,10 @@ class IronicPythonAgentHeartbeater(threading.Thread):
             )
             self.error_delay = self.initial_delay
             LOG.info('heartbeat successful')
+        except errors.HeartbeatConflictError:
+            LOG.warning('conflict error sending heartbeat')
+            self.error_delay = min(self.error_delay * self.backoff_factor,
+                                   self.max_delay)
         except Exception:
             LOG.exception('error sending heartbeat')
             self.error_delay = min(self.error_delay * self.backoff_factor,

ironic_python_agent/errors.py

@@ -109,6 +109,15 @@ class HeartbeatError(IronicAPIError):
         super(HeartbeatError, self).__init__(details)
 
 
+class HeartbeatConflictError(IronicAPIError):
+    """ConflictError raised when a heartbeat to the agent API fails."""
+
+    message = 'ConflictError heartbeating to agent API'
+
+    def __init__(self, details):
+        super(HeartbeatConflictError, self).__init__(details)
+
+
 class LookupNodeError(IronicAPIError):
     """Error raised when the node lookup to the Ironic API fails."""
 

ironic_python_agent/ironic_api_client.py

@@ -72,7 +72,10 @@ class APIClient(object):
         except Exception as e:
             raise errors.HeartbeatError(str(e))
 
-        if response.status_code != requests.codes.ACCEPTED:
+        if response.status_code == requests.codes.CONFLICT:
+            data = response.json
+            raise errors.HeartbeatConflictError(data.get('faultstring'))
+        elif response.status_code != requests.codes.ACCEPTED:
             msg = 'Invalid status code: {0}'.format(response.status_code)
             raise errors.HeartbeatError(msg)
 

ironic_python_agent/tests/unit/test_ironic_api_client.py

@@ -89,6 +89,17 @@ class TestBaseIronicPythonAgent(test_base.BaseTestCase):
                           uuid='deadbeef-dabb-ad00-b105-f00d00bab10c',
                           advertise_address=('192.0.2.1', '9999'))
 
+    def test_heartbeat_409_status_code(self):
+        response = mock.Mock()
+        response.status_code = 409
+        self.api_client.session.request = mock.Mock()
+        self.api_client.session.request.return_value = response
+
+        self.assertRaises(errors.HeartbeatConflictError,
+                          self.api_client.heartbeat,
+                          uuid='deadbeef-dabb-ad00-b105-f00d00bab10c',
+                          advertise_address=('192.0.2.1', '9999'))
+
     @mock.patch('eventlet.greenthread.sleep')
     @mock.patch('ironic_python_agent.ironic_api_client.APIClient._do_lookup')
     def test_lookup_node(self, lookup_mock, sleep_mock):