Merge "Wait for conductor start before notifying systemd"

ironic/cmd/conductor.py

@@ -67,6 +67,12 @@ def main():
     issue_startup_warnings(CONF)
 
     launcher = service.launch(CONF, mgr, restart_method='mutate')
+
+    # NOTE(dtantsur): handling start-up failures before launcher.wait() helps
+    # notify systemd about them. Otherwise the launcher will report successful
+    # service start-up before checking the threads.
+    mgr.wait_for_start()
+
     sys.exit(launcher.wait())
 
 

ironic/cmd/singleprocess.py

@@ -49,4 +49,9 @@ def main():
     wsgi = wsgi_service.WSGIService('ironic_api', CONF.api.enable_ssl_api)
     launcher.launch_service(wsgi)
 
+    # NOTE(dtantsur): handling start-up failures before launcher.wait() helps
+    # notify systemd about them. Otherwise the launcher will report successful
+    # service start-up before checking the threads.
+    mgr.wait_for_start()
+
     sys.exit(launcher.wait())

ironic/common/rpc_service.py

@@ -15,6 +15,8 @@
 # under the License.
 
 import signal
+import sys
+import time
 
 from ironic_lib.json_rpc import server as json_rpc
 from oslo_config import cfg
@@ -42,9 +44,29 @@ class RPCService(service.Service):
         self.topic = self.manager.topic
         self.rpcserver = None
         self.deregister = True
+        self._failure = None
+        self._started = False
+
+    def wait_for_start(self):
+        while not self._started and not self._failure:
+            time.sleep(0.1)
+        if self._failure:
+            LOG.critical(self._failure)
+            sys.exit(self._failure)
 
     def start(self):
+        self._failure = None
+        self._started = False
         super(RPCService, self).start()
+        try:
+            self._real_start()
+        except Exception as exc:
+            self._failure = f"{exc.__class__.__name__}: {exc}"
+            raise
+        else:
+            self._started = True
+
+    def _real_start(self):
         admin_context = context.get_admin_context()
 
         serializer = objects_base.IronicObjectSerializer(is_server=True)

ironic/tests/unit/common/test_rpc_service.py

@@ -46,6 +46,8 @@ class TestRPCService(base.TestCase):
                    mock_rpc, mock_ios, mock_target, mock_prepare_method):
         mock_rpc.return_value.start = mock.MagicMock()
         self.rpc_svc.handle_signal = mock.MagicMock()
+        self.assertFalse(self.rpc_svc._started)
+        self.assertFalse(self.rpc_svc._failure)
         self.rpc_svc.start()
         mock_ctx.assert_called_once_with()
         mock_target.assert_called_once_with(topic=self.rpc_svc.topic,
@@ -55,6 +57,9 @@ class TestRPCService(base.TestCase):
         mock_init_method.assert_called_once_with(self.rpc_svc.manager,
                                                  mock_ctx.return_value)
         self.assertIs(rpc.GLOBAL_MANAGER, self.rpc_svc.manager)
+        self.assertTrue(self.rpc_svc._started)
+        self.assertFalse(self.rpc_svc._failure)
+        self.rpc_svc.wait_for_start()  # should be no-op
 
     @mock.patch.object(manager.ConductorManager, 'prepare_host', autospec=True)
     @mock.patch.object(oslo_messaging, 'Target', autospec=True)
@@ -77,3 +82,29 @@ class TestRPCService(base.TestCase):
         mock_init_method.assert_called_once_with(self.rpc_svc.manager,
                                                  mock_ctx.return_value)
         self.assertIs(rpc.GLOBAL_MANAGER, self.rpc_svc.manager)
+
+    @mock.patch.object(manager.ConductorManager, 'prepare_host', autospec=True)
+    @mock.patch.object(oslo_messaging, 'Target', autospec=True)
+    @mock.patch.object(objects_base, 'IronicObjectSerializer', autospec=True)
+    @mock.patch.object(rpc, 'get_server', autospec=True)
+    @mock.patch.object(manager.ConductorManager, 'init_host', autospec=True)
+    @mock.patch.object(context, 'get_admin_context', autospec=True)
+    def test_start_failure(self, mock_ctx, mock_init_method, mock_rpc,
+                           mock_ios, mock_target, mock_prepare_method):
+        mock_rpc.return_value.start = mock.MagicMock()
+        self.rpc_svc.handle_signal = mock.MagicMock()
+        mock_init_method.side_effect = RuntimeError("boom")
+        self.assertFalse(self.rpc_svc._started)
+        self.assertFalse(self.rpc_svc._failure)
+        self.assertRaises(RuntimeError, self.rpc_svc.start)
+        mock_ctx.assert_called_once_with()
+        mock_target.assert_called_once_with(topic=self.rpc_svc.topic,
+                                            server="fake_host")
+        mock_ios.assert_called_once_with(is_server=True)
+        mock_prepare_method.assert_called_once_with(self.rpc_svc.manager)
+        mock_init_method.assert_called_once_with(self.rpc_svc.manager,
+                                                 mock_ctx.return_value)
+        self.assertIsNone(rpc.GLOBAL_MANAGER)
+        self.assertFalse(self.rpc_svc._started)
+        self.assertIn("boom", self.rpc_svc._failure)
+        self.assertRaises(SystemExit, self.rpc_svc.wait_for_start)

releasenotes/notes/service-wait-e85cbe7978f61764.yaml

@@ -0,0 +1,5 @@
+---
+fixes:
+  - |
+    The ``ironic`` and ``ironic-conductor`` services now wait for the conductor
+    manager to start before notifying systemd about the successful start-up.