Improve module imports

Import modules only on demand instead all on first module import

gajim/common/connection.py

@@ -492,7 +492,7 @@ class Connection(CommonConnection, ConnectionHandlers):
         self._sm_resume_data = {}
 
         # Register all modules
-        modules.register(self)
+        modules.register_modules(self)
 
         app.ged.register_event_handler('message-outgoing', ged.OUT_CORE,
             self._nec_message_outgoing)
@@ -505,7 +505,7 @@ class Connection(CommonConnection, ConnectionHandlers):
     # END __init__
 
     def cleanup(self):
-        modules.unregister(self)
+        modules.unregister_modules(self)
         app.ged.remove_event_handler('message-outgoing', ged.OUT_CORE,
             self._nec_message_outgoing)
         app.ged.remove_event_handler('gc-message-outgoing', ged.OUT_CORE,

gajim/common/modules/__init__.py

@@ -17,9 +17,9 @@ from typing import Dict  # pylint: disable=unused-import
 from typing import List
 from typing import Tuple
 
+import sys
 import logging
 from importlib import import_module
-from pathlib import Path
 from unittest.mock import MagicMock
 
 from gajim.common.types import ConnectionT
@@ -32,6 +32,49 @@ ZEROCONF_MODULES = ['iq',
                     'discovery',
                     'chatstates']
 
+MODULES = [
+    'adhoc_commands',
+    'annotations',
+    'bits_of_binary',
+    'blocking',
+    'bookmarks',
+    'caps',
+    'carbons',
+    'chatstates',
+    'delimiter',
+    'discovery',
+    'entity_time',
+    'gateway',
+    'httpupload',
+    'http_auth',
+    'iq',
+    'last_activity',
+    'mam',
+    'message',
+    'metacontacts',
+    'muc',
+    'pep',
+    'ping',
+    'presence',
+    'privacylists',
+    'pubsub',
+    'receipts',
+    'register',
+    'roster',
+    'roster_item_exchange',
+    'search',
+    'security_labels',
+    'software_version',
+    'user_activity',
+    'user_avatar',
+    'user_location',
+    'user_mood',
+    'user_nickname',
+    'user_tune',
+    'vcard_avatars',
+    'vcard_temp',
+]
+
 _imported_modules = []  # type: List[tuple]
 _modules = {}  # type: Dict[str, Dict[str, Any]]
 _store_publish_modules = [
@@ -41,20 +84,6 @@ _store_publish_modules = [
     'UserTune',
 ]  # type: List[str]
 
-for file in Path(__file__).parent.iterdir():
-    if file.stem == '__init__':
-        continue
-
-    _module = import_module('.%s' % file.stem, package='gajim.common.modules')
-    if hasattr(_module, 'get_instance'):
-        log.info('Load module: %s', file.stem)
-        if file.stem == 'pep':
-            # Register the PEP module first, because other modules
-            # depend on it
-            _imported_modules.insert(0, (_module, file.stem))
-        else:
-            _imported_modules.append((_module, file.stem))
-
 
 class ModuleMock:
     def __init__(self, name: str) -> None:
@@ -84,33 +113,32 @@ class ModuleMock:
         return MagicMock()
 
 
-def register(con: ConnectionT, *args: Any, **kwargs: Any) -> None:
+def register_modules(con: ConnectionT, *args: Any, **kwargs: Any) -> None:
     if con in _modules:
         return
     _modules[con.name] = {}
-    for module in _imported_modules:
-        mod, name = module
+    for module_name in MODULES:
         if con.name == 'Local':
-            if name not in ZEROCONF_MODULES:
+            if module_name not in ZEROCONF_MODULES:
                 continue
-        instance, name = mod.get_instance(con, *args, **kwargs)
+        instance, name = _load_module(module_name, con, *args, **kwargs)
         _modules[con.name][name] = instance
 
 
-def register_single(con: ConnectionT, instance: Any, name: str) -> None:
+def register_single_module(con: ConnectionT, instance: Any, name: str) -> None:
     if con.name not in _modules:
         raise ValueError('Unknown account name: %s' % con.name)
     _modules[con.name][name] = instance
 
 
-def unregister(con: ConnectionT) -> None:
+def unregister_modules(con: ConnectionT) -> None:
     for instance in _modules[con.name].values():
         if hasattr(instance, 'cleanup'):
             instance.cleanup()
     del _modules[con.name]
 
 
-def unregister_single(con: ConnectionT, name: str) -> None:
+def unregister_single_module(con: ConnectionT, name: str) -> None:
     if con.name not in _modules:
         return
     if name not in _modules[con.name]:
@@ -130,6 +158,15 @@ def get(account: str, name: str) -> Any:
         return ModuleMock(name)
 
 
+def _load_module(name: str, con: ConnectionT, *args: Any, **kwargs: Any) -> Any:
+    if name not in MODULES:
+        raise ValueError('Module %s does not exist' % name)
+    module = sys.modules.get(name)
+    if module is None:
+        module = import_module('.%s' % name, package='gajim.common.modules')
+    return module.get_instance(con, *args, **kwargs)  # type: ignore
+
+
 def get_handlers(con: ConnectionT) -> List[Tuple[Any, ...]]:
     handlers = []  # type: List[Tuple[Any, ...]]
     for module in _modules[con.name].values():

gajim/common/zeroconf/connection_zeroconf.py

@@ -70,7 +70,7 @@ class ConnectionZeroconf(CommonConnection, ConnectionHandlersZeroconf):
         self.is_zeroconf = True
 
         # Register all modules
-        modules.register(self)
+        modules.register_modules(self)
 
         app.ged.register_event_handler('message-outgoing', ged.OUT_CORE,
             self._nec_message_outgoing)

gajim/plugins/pluginmanager.py

@@ -408,7 +408,7 @@ class PluginManager(metaclass=Singleton):
                 if not module.zeroconf and con.name == 'Local':
                     continue
                 instance, name = module.get_instance(con)
-                modules.register_single(con, instance, name)
+                modules.register_single_module(con, instance, name)
 
                 # If handlers have been registered, register the
                 # plugin handlers. Otherwise this will be done
@@ -424,7 +424,7 @@ class PluginManager(metaclass=Singleton):
         for con in app.connections.values():
             for module in plugin.modules:
                 instance = con.get_module(module.name)
-                modules.unregister_single(con, module.name)
+                modules.unregister_single_module(con, module.name)
 
                 # Account is still connected and handlers are registered
                 # So just unregister the plugin handlers
@@ -562,7 +562,7 @@ class PluginManager(metaclass=Singleton):
                 instance, name = module.get_instance(con)
                 if not module.zeroconf and con.name == 'Local':
                     continue
-                modules.register_single(con, instance, name)
+                modules.register_single_module(con, instance, name)
 
     def _plugin_is_active_in_global_config(self, plugin):
         return app.config.get_per('plugins', plugin.short_name, 'active')