Deregister services from service registry on shutdown

CHANGELOG.rst

@@ -11,6 +11,10 @@ in development
 Added
 ~~~~~
 
+* Added service degerestration on shutdown of a service. #5396
+
+  Contributed by @khushboobhatia01
+
 * Added possibility to add new values to the KV store via CLI without leaking them to the shell history. #5164
 
 * ``st2.conf`` is now the only place to configure ports for ``st2api``, ``st2auth``, and ``st2stream``.

st2actions/st2actions/cmd/actionrunner.py

@@ -30,10 +30,12 @@
 from st2common import log as logging
 from st2common.service_setup import setup as common_setup
 from st2common.service_setup import teardown as common_teardown
+from st2common.service_setup import deregister_service
 
 __all__ = ["main"]
 
 LOG = logging.getLogger(__name__)
+ACTIONRUNNER = "actionrunner"
 
 
 def _setup_sigterm_handler():
@@ -49,7 +51,7 @@ def sigterm_handler(signum=None, frame=None):
 def _setup():
     capabilities = {"name": "actionrunner", "type": "passive"}
     common_setup(
-        service="actionrunner",
+        service=ACTIONRUNNER,
         config=config,
         setup_db=True,
         register_mq_exchanges=True,
@@ -75,6 +77,7 @@ def _run_worker():
         errors = False
 
         try:
+            deregister_service(service=ACTIONRUNNER)
             action_worker.shutdown()
         except:
             LOG.exception("Unable to shutdown worker.")

st2actions/st2actions/cmd/scheduler.py

@@ -28,10 +28,12 @@
 from st2common import log as logging
 from st2common.service_setup import teardown as common_teardown
 from st2common.service_setup import setup as common_setup
+from st2common.service_setup import deregister_service
 
 __all__ = ["main"]
 
 LOG = logging.getLogger(__name__)
+SCHEDULER = "scheduler"
 
 
 def _setup_sigterm_handler():
@@ -47,7 +49,7 @@ def sigterm_handler(signum=None, frame=None):
 def _setup():
     capabilities = {"name": "scheduler", "type": "passive"}
     common_setup(
-        service="scheduler",
+        service=SCHEDULER,
         config=config,
         setup_db=True,
         register_mq_exchanges=True,
@@ -101,6 +103,7 @@ def _run_scheduler():
         errors = False
 
         try:
+            deregister_service(service=SCHEDULER)
             handler.shutdown()
             entrypoint.shutdown()
         except:

st2actions/st2actions/cmd/st2notifier.py

@@ -25,18 +25,20 @@
 from st2common import log as logging
 from st2common.service_setup import setup as common_setup
 from st2common.service_setup import teardown as common_teardown
+from st2common.service_setup import deregister_service
 from st2actions.notifier import config
 from st2actions.notifier import notifier
 
 __all__ = ["main"]
 
 LOG = logging.getLogger(__name__)
+NOTIFIER = "notifier"
 
 
 def _setup():
     capabilities = {"name": "notifier", "type": "passive"}
     common_setup(
-        service="notifier",
+        service=NOTIFIER,
         config=config,
         setup_db=True,
         register_mq_exchanges=True,
@@ -53,6 +55,7 @@ def _run_worker():
         actions_notifier.start(wait=True)
     except (KeyboardInterrupt, SystemExit):
         LOG.info("(PID=%s) Actions notifier stopped.", os.getpid())
+        deregister_service(service=NOTIFIER)
         actions_notifier.shutdown()
     return 0
 

st2actions/st2actions/cmd/workflow_engine.py

@@ -32,10 +32,12 @@
 from st2common import log as logging
 from st2common.service_setup import setup as common_setup
 from st2common.service_setup import teardown as common_teardown
+from st2common.service_setup import deregister_service
 
 __all__ = ["main"]
 
 LOG = logging.getLogger(__name__)
+WORKFLOW_ENGINE = "workflow_engine"
 
 
 def setup_sigterm_handler():
@@ -51,7 +53,7 @@ def sigterm_handler(signum=None, frame=None):
 def setup():
     capabilities = {"name": "workflowengine", "type": "passive"}
     common_setup(
-        service="workflow_engine",
+        service=WORKFLOW_ENGINE,
         config=config,
         setup_db=True,
         register_mq_exchanges=True,
@@ -72,6 +74,7 @@ def run_server():
         engine.start(wait=True)
     except (KeyboardInterrupt, SystemExit):
         LOG.info("(PID=%s) Workflow engine stopped.", os.getpid())
+        deregister_service(service=WORKFLOW_ENGINE)
         engine.shutdown()
     except:
         LOG.exception("(PID=%s) Workflow engine unexpectedly stopped.", os.getpid())

st2api/st2api/cmd/api.py

@@ -31,6 +31,7 @@
 from st2common import log as logging
 from st2common.service_setup import setup as common_setup
 from st2common.service_setup import teardown as common_teardown
+from st2common.service_setup import deregister_service
 from st2api import config
 
 config.register_opts(ignore_errors=True)
@@ -41,6 +42,7 @@
 __all__ = ["main"]
 
 LOG = logging.getLogger(__name__)
+API = "api"
 
 # How much time to give to the request in progress to finish in seconds before killing them
 WSGI_SERVER_REQUEST_SHUTDOWN_TIME = 2
@@ -55,7 +57,7 @@ def _setup():
     }
 
     common_setup(
-        service="api",
+        service=API,
         config=config,
         setup_db=True,
         register_mq_exchanges=True,
@@ -94,6 +96,7 @@ def main():
         _setup()
         return _run_server()
     except SystemExit as exit_code:
+        deregister_service(API)
         sys.exit(exit_code)
     except Exception:
         LOG.exception("(PID=%s) ST2 API quit due to exception.", os.getpid())

st2auth/st2auth/cmd/api.py

@@ -27,6 +27,7 @@
 from st2common import log as logging
 from st2common.service_setup import setup as common_setup
 from st2common.service_setup import teardown as common_teardown
+from st2common.service_setup import deregister_service
 from st2auth import config
 
 config.register_opts(ignore_errors=True)
@@ -39,6 +40,7 @@
 
 
 LOG = logging.getLogger(__name__)
+AUTH = "auth"
 
 
 def _setup():
@@ -50,7 +52,7 @@ def _setup():
         "type": "active",
     }
     common_setup(
-        service="auth",
+        service=AUTH,
         config=config,
         setup_db=True,
         register_mq_exchanges=False,
@@ -108,6 +110,7 @@ def main():
         _setup()
         return _run_server()
     except SystemExit as exit_code:
+        deregister_service(AUTH)
         sys.exit(exit_code)
     except Exception:
         LOG.exception("(PID=%s) ST2 Auth API quit due to exception.", os.getpid())

st2common/st2common/service_setup.py

@@ -29,6 +29,8 @@
 import eventlet.debug
 from oslo_config import cfg
 from tooz.coordination import GroupAlreadyExist
+from tooz.coordination import GroupNotCreated
+from tooz.coordination import MemberNotJoined
 
 from st2common import log as logging
 from st2common.constants.logging import DEFAULT_LOGGING_CONF_PATH
@@ -62,6 +64,7 @@
     "db_setup",
     "db_teardown",
     "register_service_in_service_registry",
+    "deregister_service",
 ]
 
 # Message which is logged if non utf-8 locale is detected on startup.
@@ -339,3 +342,22 @@ def register_service_in_service_registry(service, capabilities=None, start_heart
         % (group_id, member_id, capabilities)
     )
     return coordinator.join_group(group_id, capabilities=capabilities).get()
+
+
+def deregister_service(service, start_heart=True):
+
+    if not isinstance(service, six.binary_type):
+        group_id = service.encode("utf-8")
+    else:
+        group_id = service
+
+    coordinator = coordination.get_coordinator(start_heart=start_heart)
+
+    member_id = coordination.get_member_id()
+    LOG.debug(
+        'Leaving service registry group "%s" as member_id "%s"' % (group_id, member_id)
+    )
+    try:
+        coordinator.leave_group(group_id).get()
+    except (GroupNotCreated, MemberNotJoined):
+        pass

st2common/st2common/services/coordination.py

@@ -21,6 +21,7 @@
 from tooz import coordination
 from tooz import locking
 from tooz.coordination import GroupNotCreated
+from tooz.coordination import MemberNotJoined
 
 from st2common import log as logging
 from st2common.util import system_info
@@ -124,8 +125,15 @@ def join_group(cls, group_id, capabilities=""):
     @classmethod
     def leave_group(cls, group_id):
         member_id = get_member_id()
+        try:
+            members = cls.groups[group_id]["members"]
+        except KeyError:
+            raise GroupNotCreated(group_id)
 
-        del cls.groups[group_id]["members"][member_id]
+        try:
+            del members[member_id]
+        except KeyError:
+            raise MemberNotJoined(group_id, member_id)
         return NoOpAsyncResult()
 
     @classmethod

st2common/tests/unit/test_service_setup.py

@@ -23,6 +23,7 @@
 from oslo_config.cfg import ConfigFilesNotFoundError
 
 from st2common import service_setup
+from st2common.services import coordination
 from st2common.transport.bootstrap_utils import register_exchanges
 from st2common.transport.bootstrap_utils import QUEUES
 
@@ -216,3 +217,23 @@ def mock_get_logging_config_path():
             run_migrations=False,
             register_runners=False,
         )
+
+    def test_deregister_service_when_service_registry_enabled(self):
+        service = "api"
+        service_setup.register_service_in_service_registry(
+            service, capabilities={"hostname": "", "pid": ""}
+        )
+        coordinator = coordination.get_coordinator(start_heart=True)
+        members = coordinator.get_members(service.encode("utf-8"))
+        self.assertEqual(len(list(members.get())), 1)
+        service_setup.deregister_service(service)
+        self.assertEqual(len(list(members.get())), 0)
+
+    def test_deregister_service_when_service_registry_disables(self):
+        service = "api"
+        try:
+            service_setup.deregister_service(service)
+        except:
+            assert False, "service_setup.deregister_service raised exception"
+
+        assert True

st2reactor/st2reactor/cmd/garbagecollector.py

@@ -28,6 +28,7 @@
 from st2common.logging.misc import get_logger_name_for_module
 from st2common.service_setup import setup as common_setup
 from st2common.service_setup import teardown as common_teardown
+from st2common.service_setup import deregister_service
 from st2common.constants.exit_codes import FAILURE_EXIT_CODE
 from st2reactor.garbage_collector import config
 from st2reactor.garbage_collector.base import GarbageCollectorService
@@ -37,12 +38,13 @@
 
 LOGGER_NAME = get_logger_name_for_module(sys.modules[__name__])
 LOG = logging.getLogger(LOGGER_NAME)
+GARBAGE_COLLECTOR = "garbagecollector"
 
 
 def _setup():
     capabilities = {"name": "garbagecollector", "type": "passive"}
     common_setup(
-        service="garbagecollector",
+        service=GARBAGE_COLLECTOR,
         config=config,
         setup_db=True,
         register_mq_exchanges=True,
@@ -68,6 +70,7 @@ def main():
         )
         exit_code = garbage_collector.run()
     except SystemExit as exit_code:
+        deregister_service(GARBAGE_COLLECTOR)
         return exit_code
     except:
         LOG.exception("(PID:%s) GarbageCollector quit due to exception.", os.getpid())

st2reactor/st2reactor/cmd/rulesengine.py

@@ -26,18 +26,20 @@
 from st2common.logging.misc import get_logger_name_for_module
 from st2common.service_setup import setup as common_setup
 from st2common.service_setup import teardown as common_teardown
+from st2common.service_setup import deregister_service
 from st2reactor.rules import config
 from st2reactor.rules import worker
 
 
 LOGGER_NAME = get_logger_name_for_module(sys.modules[__name__])
 LOG = logging.getLogger(LOGGER_NAME)
+RULESENGINE = "rulesengine"
 
 
 def _setup():
     capabilities = {"name": "rulesengine", "type": "passive"}
     common_setup(
-        service="rulesengine",
+        service=RULESENGINE,
         config=config,
         setup_db=True,
         register_mq_exchanges=True,
@@ -63,6 +65,7 @@ def _run_worker():
         return rules_engine_worker.wait()
     except (KeyboardInterrupt, SystemExit):
         LOG.info("(PID=%s) RulesEngine stopped.", os.getpid())
+        deregister_service(RULESENGINE)
         rules_engine_worker.shutdown()
     except:
         LOG.exception("(PID:%s) RulesEngine quit due to exception.", os.getpid())

st2reactor/st2reactor/cmd/sensormanager.py

@@ -28,6 +28,7 @@
 from st2common.logging.misc import get_logger_name_for_module
 from st2common.service_setup import setup as common_setup
 from st2common.service_setup import teardown as common_teardown
+from st2common.service_setup import deregister_service
 from st2common.exceptions.sensors import SensorNotFoundException
 from st2common.constants.exit_codes import FAILURE_EXIT_CODE
 from st2reactor.sensor import config
@@ -39,12 +40,13 @@
 
 LOGGER_NAME = get_logger_name_for_module(sys.modules[__name__])
 LOG = logging.getLogger(LOGGER_NAME)
+SENSOR_CONTAINER = "sensorcontainer"
 
 
 def _setup():
     capabilities = {"name": "sensorcontainer", "type": "passive"}
     common_setup(
-        service="sensorcontainer",
+        service=SENSOR_CONTAINER,
         config=config,
         setup_db=True,
         register_mq_exchanges=True,
@@ -80,6 +82,7 @@ def main():
         )
         return container_manager.run_sensors()
     except SystemExit as exit_code:
+        deregister_service(SENSOR_CONTAINER)
         return exit_code
     except SensorNotFoundException as e:
         LOG.exception(e)