[Modular] guard ModularPipeline.blocks attribute (#13014)

* up

* style

Author: yiyixuxu

src/diffusers/modular_pipelines/modular_pipeline.py

@@ -1598,11 +1598,11 @@ def __init__(
             else:
                 logger.warning(f"`blocks` is `None`, no default blocks class found for {self.__class__.__name__}")
 
-        self.blocks = blocks
+        self._blocks = blocks
         self._components_manager = components_manager
         self._collection = collection
-        self._component_specs = {spec.name: deepcopy(spec) for spec in self.blocks.expected_components}
-        self._config_specs = {spec.name: deepcopy(spec) for spec in self.blocks.expected_configs}
+        self._component_specs = {spec.name: deepcopy(spec) for spec in self._blocks.expected_components}
+        self._config_specs = {spec.name: deepcopy(spec) for spec in self._blocks.expected_configs}
 
         # update component_specs and config_specs based on modular_model_index.json
         if modular_config_dict is not None:
@@ -1649,7 +1649,9 @@ def __init__(
         for name, config_spec in self._config_specs.items():
             default_configs[name] = config_spec.default
         self.register_to_config(**default_configs)
-        self.register_to_config(_blocks_class_name=self.blocks.__class__.__name__ if self.blocks is not None else None)
+        self.register_to_config(
+            _blocks_class_name=self._blocks.__class__.__name__ if self._blocks is not None else None
+        )
 
     @property
     def default_call_parameters(self) -> Dict[str, Any]:
@@ -1658,7 +1660,7 @@ def default_call_parameters(self) -> Dict[str, Any]:
             - Dictionary mapping input names to their default values
         """
         params = {}
-        for input_param in self.blocks.inputs:
+        for input_param in self._blocks.inputs:
             params[input_param.name] = input_param.default
         return params
 
@@ -1829,7 +1831,15 @@ def doc(self):
         Returns:
             - The docstring of the pipeline blocks
         """
-        return self.blocks.doc
+        return self._blocks.doc
+
+    @property
+    def blocks(self) -> ModularPipelineBlocks:
+        """
+        Returns:
+            - A copy of the pipeline blocks
+        """
+        return deepcopy(self._blocks)
 
     def register_components(self, **kwargs):
         """
@@ -2565,7 +2575,7 @@ def _dict_to_component_spec(
         )
 
     def set_progress_bar_config(self, **kwargs):
-        for sub_block_name, sub_block in self.blocks.sub_blocks.items():
+        for sub_block_name, sub_block in self._blocks.sub_blocks.items():
             if hasattr(sub_block, "set_progress_bar_config"):
                 sub_block.set_progress_bar_config(**kwargs)
 
@@ -2619,7 +2629,7 @@ def __call__(self, state: PipelineState = None, output: Union[str, List[str]] =
 
         # Add inputs to state, using defaults if not provided in the kwargs or the state
         # if same input already in the state, will override it if provided in the kwargs
-        for expected_input_param in self.blocks.inputs:
+        for expected_input_param in self._blocks.inputs:
             name = expected_input_param.name
             default = expected_input_param.default
             kwargs_type = expected_input_param.kwargs_type
@@ -2638,9 +2648,9 @@ def __call__(self, state: PipelineState = None, output: Union[str, List[str]] =
         # Run the pipeline
         with torch.no_grad():
             try:
-                _, state = self.blocks(self, state)
+                _, state = self._blocks(self, state)
             except Exception:
-                error_msg = f"Error in block: ({self.blocks.__class__.__name__}):\n"
+                error_msg = f"Error in block: ({self._blocks.__class__.__name__}):\n"
                 logger.error(error_msg)
                 raise