Merge "gracefully exit daemonserver before registry exit"

kuryr_kubernetes/cni/daemon/service.py

@@ -28,6 +28,7 @@ import cotyledon
 import flask
 import pyroute2
 from pyroute2.ipdb import transactional
+from werkzeug import serving
 
 import os_vif
 from oslo_concurrency import lockutils
@@ -68,6 +69,7 @@ class DaemonServer(object):
             '/delNetwork', methods=['POST'], view_func=self.delete)
         self.headers = {'ContentType': 'application/json',
                         'Connection': 'close'}
+        self._server = None
 
     def _prepare_request(self):
         params = cni_utils.CNIParameters(flask.request.get_json())
@@ -184,12 +186,21 @@ class DaemonServer(object):
             raise
 
         try:
-            self.application.run(address, port, threaded=False,
-                                 processes=CONF.cni_daemon.worker_num)
+            self._server = serving.make_server(
+                address, port, self.application, threaded=False,
+                processes=CONF.cni_daemon.worker_num)
+            self._server.serve_forever()
         except Exception:
             LOG.exception('Failed to start kuryr-daemon.')
             raise
 
+    def stop(self):
+        LOG.info("Waiting for DaemonServer worker processes to exit...")
+        self._server._block_on_close = True
+        self._server.shutdown()
+        self._server.server_close()
+        LOG.info("All DaemonServer workers finished gracefully.")
+
     def _check_failure(self):
         with self.failure_count.get_lock():
             if self.failure_count.value < CONF.cni_daemon.cni_failures_count:
@@ -221,6 +232,9 @@ class CNIDaemonServerService(cotyledon.Service):
         # Run HTTP server
         self.server.run()
 
+    def terminate(self):
+        self.server.stop()
+
 
 class CNIDaemonWatcherService(cotyledon.Service):
     name = "watcher"
@@ -328,6 +342,8 @@ class CNIDaemonHealthServerService(cotyledon.Service):
 
 class CNIDaemonServiceManager(cotyledon.ServiceManager):
     def __init__(self):
+        # NOTE(mdulko): Default shutdown timeout is 60 seconds and K8s won't
+        #               wait more by default anyway.
         super(CNIDaemonServiceManager, self).__init__()
         # TODO(dulek): Use cotyledon.oslo_config_glue to support conf reload.
 
@@ -344,7 +360,8 @@ class CNIDaemonServiceManager(cotyledon.ServiceManager):
         registry = self.manager.dict()  # For Watcher->Server communication.
         healthy = multiprocessing.Value(c_bool, True)
         self.add(CNIDaemonWatcherService, workers=1, args=(registry, healthy,))
-        self.add(CNIDaemonServerService, workers=1, args=(registry, healthy,))
+        self._server_service = self.add(
+            CNIDaemonServerService, workers=1, args=(registry, healthy))
         self.add(CNIDaemonHealthServerService, workers=1, args=(healthy,))
         self.register_hooks(on_terminate=self.terminate)
 
@@ -379,7 +396,15 @@ class CNIDaemonServiceManager(cotyledon.ServiceManager):
 
     def terminate(self):
         self._terminate_called.set()
+        LOG.info("Gracefully stopping DaemonServer service..")
+        self.reconfigure(self._server_service, 0)
+        for worker in self._running_services[self._server_service]:
+            worker.terminate()
+        for worker in self._running_services[self._server_service]:
+            worker.join()
+        LOG.info("Stopping registry manager...")
         self.manager.shutdown()
+        LOG.info("Continuing with shutdown")
 
 
 def start():