sma: handle SIGINT and SIGTERM signals

If the app is killed with either one of these signals, it'll shutdown
gracefully and exit with zero.

Signed-off-by: Konrad Sztyber <konrad.sztyber@intel.com>
Change-Id: I630f9e34c3ccb382c8e1b53d0f589f3ec4d1483b
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/11727
Community-CI: Broadcom CI <spdk-ci.pdl@broadcom.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>

python/spdk/sma/sma.py

@@ -24,9 +24,11 @@ class StorageManagementAgent(pb2_grpc.StorageManagementAgentServicer):
     def register_device(self, device_manager):
         self._devices[device_manager.protocol] = device_manager
 
-    def run(self):
+    def start(self):
         self._server.start()
-        self._server.wait_for_termination()
+
+    def stop(self):
+        self._server.stop(None)
 
     def _find_device_by_name(self, name):
         return self._devices.get(name)

scripts/sma.py

@@ -4,7 +4,9 @@ from argparse import ArgumentParser
 import importlib
 import logging
 import os
+import signal
 import sys
+import threading
 import yaml
 
 sys.path.append(os.path.dirname(__file__) + '/../python')
@@ -72,6 +74,20 @@ def load_plugins(plugins, client):
     return devices
 
 
+def run(agent):
+    event = threading.Event()
+
+    def signal_handler(signum, frame):
+        event.set()
+
+    for signum in [signal.SIGTERM, signal.SIGINT]:
+        signal.signal(signum, signal_handler)
+
+    agent.start()
+    event.wait()
+    agent.stop()
+
+
 if __name__ == '__main__':
     logging.basicConfig(level=os.environ.get('SMA_LOGLEVEL', 'WARNING').upper())
 
@@ -85,5 +101,4 @@ if __name__ == '__main__':
     devices += load_plugins(filter(None, os.environ.get('SMA_PLUGINS', '').split(':')),
                             client)
     register_devices(agent, devices, config)
-
-    agent.run()
+    run(agent)