Install a SIGTERM handler in addition to SIGINT (#1246)

This allows cleanly terminating CMS by sending it SIGTERM, which is what
e.g. Docker or systemd do.

cms/io/service.py

@@ -78,6 +78,7 @@ class Service:
 
     def __init__(self, shard=0):
         signal.signal(signal.SIGINT, lambda unused_x, unused_y: self.exit())
+        signal.signal(signal.SIGTERM, lambda unused_x, unused_y: self.exit())
 
         self.name = self.__class__.__name__
         self.shard = shard

cmsranking/RankingWebServer.py

@@ -24,6 +24,7 @@ import os
 import pprint
 import re
 import shutil
+import signal
 import time
 from datetime import datetime
 
@@ -622,6 +623,10 @@ def main():
             certfile=config.https_certfile, keyfile=config.https_keyfile)
         servers.append(https_server)
 
+    def sigterm_handler(*_):
+        raise KeyboardInterrupt
+    signal.signal(signal.SIGTERM, sigterm_handler)
+
     try:
         gevent.joinall(list(gevent.spawn(s.serve_forever) for s in servers))
     except KeyboardInterrupt: