working on improving component loading

src/myfasthtml/core/instances.py

@@ -3,7 +3,7 @@ import uuid
 from typing import Optional
 
 from myfasthtml.controls.helpers import Ids
-from myfasthtml.core.utils import pascal_to_snake
+from myfasthtml.core.utils import pascal_to_snake, get_class, snake_to_pascal
 
 logger = logging.getLogger("InstancesManager")
 
@@ -183,16 +183,22 @@ class InstancesManager:
     return instance
   
   @staticmethod
-  def get(session: dict, instance_id: str):
+  def get(session: dict, instance_id: str, default="**__no_default__**"):
     """
     Get or create an instance of the given type (from its id)
     :param session:
     :param instance_id:
+    :param default:
     :return:
     """
-    session_id = InstancesManager.get_session_id(session)
-    key = (session_id, instance_id)
-    return InstancesManager.instances[key]
+    try:
+      session_id = InstancesManager.get_session_id(session)
+      key = (session_id, instance_id)
+      return InstancesManager.instances[key]
+    except KeyError:
+      if default != "**__non__**":
+        return default
+      raise
   
   @staticmethod
   def get_by_type(session: dict, cls: type):
@@ -202,6 +208,19 @@ class InstancesManager:
     assert len(res) > 0, f"No instance of type {cls.__name__} found"
     return res[0]
   
+  @staticmethod
+  def dynamic_get(session, component_parent: tuple, component: tuple):
+    parent_type, parent_id = component_parent
+    component_type, component_id = component
+    
+    # parent should always exist
+    parent = InstancesManager.get(session, parent_id)
+    
+    real_component_type = snake_to_pascal(component_type.removeprefix("mf-"))
+    component_full_type = f"myfasthtml.controls.{real_component_type}.{real_component_type}"
+    cls = get_class(component_full_type)
+    return cls(parent, _id=component_id)
+  
   @staticmethod
   def get_session_id(session):
     if isinstance(session, str):

src/myfasthtml/core/utils.py

@@ -1,3 +1,4 @@
+import importlib
 import logging
 import re
 
@@ -317,6 +318,29 @@ def make_safe_id(s: str | None):
   res = re.sub('-', '_', make_html_id(s))  # replace '-' by '_'
   return res.lower()  # no uppercase
 
+
+def get_class(qualified_class_name: str):
+  """
+    Dynamically loads and returns a class type from its fully qualified name.
+    Note that the class is not instantiated.
+
+    :param qualified_class_name: Fully qualified name of the class (e.g., 'some.module.ClassName').
+    :return: The class object.
+    :raises ImportError: If the module cannot be imported.
+    :raises AttributeError: If the class cannot be resolved in the module.
+    """
+  module_name, class_name = qualified_class_name.rsplit(".", 1)
+  
+  try:
+    module = importlib.import_module(module_name)
+  except ModuleNotFoundError as e:
+    raise ImportError(f"Could not import module '{module_name}' for '{qualified_class_name}': {e}")
+  
+  if not hasattr(module, class_name):
+    raise AttributeError(f"Component '{class_name}' not found in '{module.__name__}'.")
+  
+  return getattr(module, class_name)
+
 @utils_rt(Routes.Commands)
 def post(session, c_id: str, client_response: dict = None):
   """