zulip-run-bot: Add the ability to run a bot by the module name.

zulip_bots/zulip_bots/finder.py

@@ -23,12 +23,22 @@ def import_module_from_source(path: Text, name: Text) -> Any:
 
     return module
 
-def resolve_bot_path(name: Text) -> Tuple[Text, Text]:
+def import_module_by_name(name: Text) -> Any:
+    import importlib
+    try:
+        return importlib.import_module(name)
+    except ModuleNotFoundError:
+        return None
+
+def resolve_bot_path(name: Text) -> Optional[Tuple[Text, Text]]:
     if os.path.isfile(name):
         bot_path = os.path.abspath(name)
         bot_name = splitext(basename(bot_path))[0]
-    else:
-        bot_path = os.path.abspath(os.path.join(current_dir, 'bots', name, name + '.py'))
-        bot_name = name
-
         return (bot_path, bot_name)
+    else:
+        bot_name = name
+        bot_path = os.path.abspath(os.path.join(current_dir, 'bots', bot_name, bot_name + '.py'))
+        if os.path.isfile(bot_path):
+            return (bot_path, bot_name)
+
+    return None

zulip_bots/zulip_bots/run.py

@@ -81,7 +81,9 @@ def exit_gracefully_if_bot_config_file_does_not_exist(bot_config_file: str) -> N
 def main() -> None:
     args = parse_args()
 
-    bot_path, bot_name = finder.resolve_bot_path(args.bot)
+    result = finder.resolve_bot_path(args.bot)
+    if result:
+        bot_path, bot_name = result
         sys.path.insert(0, os.path.dirname(bot_path))
 
         if args.provision:
@@ -100,6 +102,13 @@ def main() -> None:
                            "    zulip-run-bot {bot_name} --provision")
             print(dep_err_msg.format(bot_name=bot_name, deps_list=deps_list))
             sys.exit(1)
+    else:
+        lib_module = finder.import_module_by_name(args.bot)
+        if lib_module:
+            bot_name = lib_module.__name__
+            if args.provision:
+                print("ERROR: Could not load bot's module for '{}'. Exiting now.")
+                sys.exit(1)
 
     if lib_module is None:
         print("ERROR: Could not load bot module. Exiting now.")

zulip_bots/zulip_bots/tests/test_run.py

@@ -42,7 +42,7 @@ class TestDefaultArguments(TestCase):
             quiet=False)
 
     def test_adding_bot_parent_dir_to_sys_path_when_bot_name_specified(self) -> None:
-        bot_name = 'any_bot_name'
+        bot_name = 'helloworld'  # existing bot's name
         expected_bot_dir_path = os.path.join(
             os.path.dirname(zulip_bots.run.__file__),
             'bots',
@@ -66,6 +66,18 @@ class TestDefaultArguments(TestCase):
 
         self.assertIn(bot_dir_path, sys.path)
 
+    @patch('os.path.isfile', return_value=False)
+    def test_run_bot_by_module_name(self, mock_os_path_isfile: mock.Mock) -> None:
+        bot_module_name = 'bot.module.name'
+        mock_bot_module = mock.Mock()
+        mock_bot_module.__name__ = bot_module_name
+        with patch('sys.argv', ['zulip-run-bot', 'bot.module.name', '--config-file', '/path/to/config']):
+            with patch('importlib.import_module', return_value=mock_bot_module) as mock_import_module:
+                with patch('zulip_bots.run.run_message_handler_for_bot'):
+                        with patch('zulip_bots.run.exit_gracefully_if_zulip_config_file_does_not_exist'):
+                            zulip_bots.run.main()
+                            mock_import_module.assert_called_once_with(bot_module_name)
+
 
 class TestBotLib(TestCase):
     def test_extract_query_without_mention(self) -> None: