Log signal handling at notice

Signals feel like they belong with the other process-management info
we already log at notice -- more important than a simple info(), but
definitely not an error().

While we're at it, have Daemon include the receiving pid when logging
about SIGTERM.

Change-Id: I787b9d5a35ce760450bc7389b53f0540f70c8d76

swift/common/daemon.py

@@ -138,7 +138,7 @@ class DaemonStrategy(object):
 
         def kill_children(*args):
             self.running = False
-            self.logger.info('SIGTERM received')
+            self.logger.notice('SIGTERM received (%s)', os.getpid())
             signal.signal(signal.SIGTERM, signal.SIG_IGN)
             os.killpg(0, signal.SIGTERM)
             os._exit(0)

swift/common/wsgi.py

@@ -1163,7 +1163,7 @@ def run_wsgi(conf_path, app_section, *args, **kwargs):
             logger.error('Stopping with unexpected signal %r' %
                          running_context[1])
         else:
-            logger.error('%s received (%s)', signame, os.getpid())
+            logger.notice('%s received (%s)', signame, os.getpid())
     if running_context[1] == signal.SIGTERM:
         os.killpg(0, signal.SIGTERM)
     elif running_context[1] == signal.SIGUSR1:

test/unit/common/test_daemon.py

@@ -139,6 +139,7 @@ class TestRunDaemon(unittest.TestCase):
         with mock.patch('swift.common.daemon.os') as mock_os:
             func()
         self.assertEqual(mock_os.method_calls, [
+            mock.call.getpid(),
             mock.call.killpg(0, signal.SIGTERM),
             # hard exit because bare except handlers can trap SystemExit
             mock.call._exit(0)