Implement restart functionality

sopel/__init__.py

@@ -71,6 +71,9 @@ def signal_handler(sig, frame):
         if sig == signal.SIGUSR1 or sig == signal.SIGTERM or sig == signal.SIGINT:
             stderr('Got quit signal, shutting down.')
             p.quit('Closing')
+        elif sig == signal.SIGUSR2 or sig == signal.SIGILL:
+            stderr('Got restart signal.')
+            p.restart('Restarting')
     while True:
         try:
             p = bot.Sopel(config, daemon=daemon)
@@ -80,6 +83,10 @@ def signal_handler(sig, frame):
                 signal.signal(signal.SIGTERM, signal_handler)
             if hasattr(signal, 'SIGINT'):
                 signal.signal(signal.SIGINT, signal_handler)
+            if hasattr(signal, 'SIGUSR2'):
+                signal.signal(signal.SIGUSR2, signal_handler)
+            if hasattr(signal, 'SIGILL'):
+                signal.signal(signal.SIGILL, signal_handler)
             sopel.logger.setup_logging(p)
             p.run(config.core.host, int(config.core.port))
         except KeyboardInterrupt:
@@ -95,14 +102,24 @@ def signal_handler(sig, frame):
             logfile.write(trace)
             logfile.write('----------------------------------------\n\n')
             logfile.close()
+            # TODO: This should be handled in run_script
+            # All we should need here is a return value, but replacing the
+            # os._exit() call below (at the end) broke ^C.
+            # This one is much harder to test, so until that one's sorted it
+            # isn't worth the risk of trying to remove this one.
             os.unlink(pid_file)
             os._exit(1)
 
         if not isinstance(delay, int):
             break
+        if p.wantsrestart:
+            return -1
         if p.hasquit:
             break
         stderr('Warning: Disconnected. Reconnecting in %s seconds...' % delay)
         time.sleep(delay)
+    # TODO: This should be handled in run_script
+    # All we should need here is a return value, but making this
+    # a return makes Sopel hang on ^C after it says "Closed!"
     os.unlink(pid_file)
     os._exit(0)

sopel/irc.py

@@ -62,6 +62,7 @@ def __init__(self, config):
         self.ca_certs = ca_certs
         self.enabled_capabilities = set()
         self.hasquit = False
+        self.wantsrestart = False
 
         self.sending = threading.RLock()
         self.writing_lock = threading.Lock()
@@ -176,6 +177,12 @@ def initiate_connect(self, host, port):
             print('KeyboardInterrupt')
             self.quit('KeyboardInterrupt')
 
+    def restart(self, message):
+        """Disconnect from IRC and restart the bot."""
+        self.write(['QUIT'], message)
+        self.wantsrestart = True
+        self.hasquit = True
+
     def quit(self, message):
         """Disconnect from IRC and close the bot."""
         self.write(['QUIT'], message)

sopel/modules/admin.py

@@ -74,6 +74,19 @@ def part(bot, trigger):
         bot.part(channel)
 
 
+@sopel.module.require_privmsg
+@sopel.module.require_owner
+@sopel.module.commands('restart')
+@sopel.module.priority('low')
+def restart(bot, trigger):
+    """Restart the bot. This is an owner-only command."""
+    quit_message = trigger.group(2)
+    if not quit_message:
+        quit_message = 'Restart on command from %s' % trigger.nick
+
+    bot.restart(quit_message)
+
+
 @sopel.module.require_privmsg
 @sopel.module.require_owner
 @sopel.module.commands('quit')

sopel/run_script.py

@@ -117,7 +117,7 @@ def find_config(config_dir, name, extension='.cfg'):
 def build_parser():
     """Build an ``argparse.ArgumentParser`` for the bot"""
     parser = argparse.ArgumentParser(description='Sopel IRC Bot',
-                                        usage='%(prog)s [options]')
+                                     usage='%(prog)s [options]')
     parser.add_argument('-c', '--config', metavar='filename',
                         help='use a specific configuration file')
     parser.add_argument("-d", '--fork', action="store_true",
@@ -126,6 +126,8 @@ def build_parser():
                         help="Gracefully quit Sopel")
     parser.add_argument("-k", '--kill', action="store_true", dest="kill",
                         help="Kill Sopel")
+    parser.add_argument("-r", '--restart', action="store_true", dest="restart",
+                        help="Restart Sopel")
     parser.add_argument("-l", '--list', action="store_true",
                         dest="list_configs",
                         help="List all config files found")
@@ -303,9 +305,9 @@ def main(argv=None):
         old_pid = get_running_pid(pid_file_path)
 
         if old_pid is not None and tools.check_pid(old_pid):
-            if not opts.quit and not opts.kill:
+            if not opts.quit and not opts.kill and not opts.restart:
                 stderr('There\'s already a Sopel instance running with this config file')
-                stderr('Try using the --quit or the --kill options')
+                stderr('Try using either the --quit, --restart, or --kill option')
                 return ERR_CODE
             elif opts.kill:
                 stderr('Killing the Sopel')
@@ -316,9 +318,20 @@ def main(argv=None):
                 if hasattr(signal, 'SIGUSR1'):
                     os.kill(old_pid, signal.SIGUSR1)
                 else:
+                    # Windows will not generate SIGTERM itself
+                    # https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/signal
                     os.kill(old_pid, signal.SIGTERM)
                 return
-        elif opts.kill or opts.quit:
+            elif opts.restart:
+                stderr('Asking Sopel to restart')
+                if hasattr(signal, 'SIGUSR2'):
+                    os.kill(old_pid, signal.SIGUSR2)
+                else:
+                    # Windows will not generate SIGILL itself
+                    # https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/signal
+                    os.kill(old_pid, signal.SIGILL)
+                return
+        elif opts.kill or opts.quit or opts.restart:
             stderr('Sopel is not running!')
             return ERR_CODE
 
@@ -330,7 +343,13 @@ def main(argv=None):
             pid_file.write(str(os.getpid()))
 
         # Step Seven: Initialize and run Sopel
-        run(config_module, pid_file_path)
+        ret = run(config_module, pid_file_path)
+        os.unlink(pid_file_path)
+        if ret == -1:
+            os.execv(sys.executable, ['python'] + sys.argv)
+        else:
+            return ret
+
     except KeyboardInterrupt:
         print("\n\nInterrupted")
         return ERR_CODE