Updater: Issue INFO log upon received signal (#951)

Fixes #946

AUTHORS.rst

@@ -45,6 +45,7 @@ The following wonderful people contributed directly or indirectly to this projec
 - `Li-aung Yip <https://github.com/LiaungYip>`_
 - `macrojames <https://github.com/macrojames>`_
 - `Michael Elovskikh <https://github.com/wronglink>`_
+- `Mischa Krüger <https://github.com/Makman2>`_
 - `naveenvhegde <https://github.com/naveenvhegde>`_
 - `neurrone <https://github.com/neurrone>`_
 - `njittam <https://github.com/njittam>`_

requirements-dev.txt

@@ -6,4 +6,5 @@ yapf
 pre-commit
 beautifulsoup4
 pytest
+pytest-catchlog
 pytest-timeout

telegram/ext/updater.py

@@ -31,6 +31,7 @@ from queue import Queue
 from telegram import Bot, TelegramError
 from telegram.ext import Dispatcher, JobQueue
 from telegram.error import Unauthorized, InvalidToken, RetryAfter
+from telegram.utils.helpers import get_signal_name
 from telegram.utils.request import Request
 from telegram.utils.webhookhandler import (WebhookServer, WebhookHandler)
 
@@ -449,6 +450,8 @@ class Updater(object):
     def signal_handler(self, signum, frame):
         self.is_idle = False
         if self.running:
+            self.logger.info('Received signal {} ({}), stopping...'.format(
+                signum, get_signal_name(signum)))
             self.stop()
             if self.user_sig_handler:
                 self.user_sig_handler(signum, frame)

telegram/utils/helpers.py

@@ -19,6 +19,7 @@
 """This module contains helper functions."""
 
 import re
+import signal
 from datetime import datetime
 
 try:
@@ -26,6 +27,18 @@ try:
 except ImportError:
     from cgi import escape as escape_html  # noqa: F401
 
+
+# From https://stackoverflow.com/questions/2549939/get-signal-names-from-numbers-in-python
+_signames = {v: k
+             for k, v in reversed(sorted(vars(signal).items()))
+             if k.startswith('SIG') and not k.startswith('SIG_')}
+
+
+def get_signal_name(signum):
+    """Returns the signal name of the given signal number."""
+    return _signames[signum]
+
+
 # Not using future.backports.datetime here as datetime value might be an input from the user,
 # making every isinstace() call more delicate. So we just use our own compat layer.
 if hasattr(datetime, 'timestamp'):

tests/test_updater.py

@@ -16,9 +16,11 @@
 #
 # You should have received a copy of the GNU Lesser Public License
 # along with this program.  If not, see [http://www.gnu.org/licenses/].
+import logging
 import os
 import signal
 import sys
+from functools import partial
 from queue import Queue
 from random import randrange
 from threading import Thread
@@ -238,15 +240,25 @@ class TestUpdater(object):
 
         return urlopen(req)
 
-    def signal_sender(self):
+    def signal_sender(self, updater):
         sleep(0.2)
+        while not updater.running:
+            sleep(0.2)
+
         os.kill(os.getpid(), signal.SIGTERM)
 
     @signalskip
-    def test_idle(self, updater):
+    def test_idle(self, updater, caplog):
         updater.start_polling(0.01)
-        Thread(target=self.signal_sender).start()
-        updater.idle()
+        Thread(target=partial(self.signal_sender, updater=updater)).start()
+
+        with caplog.at_level(logging.INFO):
+            updater.idle()
+
+        rec = caplog.records[-1]
+        assert rec.msg.startswith('Received signal {}'.format(signal.SIGTERM))
+        assert rec.levelname == 'INFO'
+
         # If we get this far, idle() ran through
         sleep(.5)
         assert updater.running is False
@@ -260,7 +272,7 @@ class TestUpdater(object):
 
         updater.user_sig_handler = user_signal_inc
         updater.start_polling(0.01)
-        Thread(target=self.signal_sender).start()
+        Thread(target=partial(self.signal_sender, updater=updater)).start()
         updater.idle()
         # If we get this far, idle() ran through
         sleep(.5)