Remove core safetensors->diffusers conversion models

- No longer install core conversion models. Use the HuggingFace cache to load
  them if and when needed.

- Call directly into the diffusers library to perform conversions with only shallow
   wrappers around them to massage arguments, etc.

- At root configuration time, do not create all the possible model subdirectories,
  but let them be created and populated at model install time.

- Remove checks for missing core conversion files, since they are no
  longer installed.

invokeai/backend/model_manager/load/model_loaders/controlnet.py

@@ -3,9 +3,6 @@
 
 from pathlib import Path
 
-import torch
-from safetensors.torch import load_file as safetensors_load_file
-
 from invokeai.backend.model_manager import (
     AnyModelConfig,
     BaseModelType,
@@ -37,27 +34,25 @@ class ControlNetLoader(GenericDiffusersLoader):
             return True
 
     def _convert_model(self, config: AnyModelConfig, model_path: Path, output_path: Path) -> Path:
-        if config.base not in {BaseModelType.StableDiffusion1, BaseModelType.StableDiffusion2}:
-            raise Exception(f"ControlNet conversion not supported for model type: {config.base}")
-        else:
-            assert isinstance(config, CheckpointConfigBase)
-            config_file = config.config_path
+        assert isinstance(config, CheckpointConfigBase)
+        config_file = config.config_path
 
-        if model_path.suffix == ".safetensors":
-            checkpoint = safetensors_load_file(model_path, device="cpu")
-        else:
-            checkpoint = torch.load(model_path, map_location="cpu")
-
-        # sometimes weights are hidden under "state_dict", and sometimes not
-        if "state_dict" in checkpoint:
-            checkpoint = checkpoint["state_dict"]
-
-        convert_controlnet_to_diffusers(
-            model_path,
-            output_path,
-            original_config_file=self._app_config.root_path / config_file,
-            image_size=512,
-            scan_needed=True,
-            from_safetensors=model_path.suffix == ".safetensors",
+        image_size = (
+            512
+            if config.base == BaseModelType.StableDiffusion1
+            else 768
+            if config.base == BaseModelType.StableDiffusion2
+            else 1024
         )
+
+        self._logger.info(f"Converting {model_path} to diffusers format")
+        with open(self._app_config.root_path / config_file, "r") as config_stream:
+            convert_controlnet_to_diffusers(
+                model_path,
+                output_path,
+                original_config_file=config_stream,
+                image_size=image_size,
+                precision=self._torch_dtype,
+                from_safetensors=model_path.suffix == ".safetensors",
+            )
         return output_path

invokeai/backend/model_manager/load/model_loaders/stable_diffusion.py

@@ -4,9 +4,6 @@
 from pathlib import Path
 from typing import Optional
 
-from diffusers.pipelines.stable_diffusion.pipeline_stable_diffusion import StableDiffusionPipeline
-from diffusers.pipelines.stable_diffusion.pipeline_stable_diffusion_inpaint import StableDiffusionInpaintPipeline
-
 from invokeai.backend.model_manager import (
     AnyModel,
     AnyModelConfig,
@@ -14,7 +11,7 @@ from invokeai.backend.model_manager import (
     ModelFormat,
     ModelRepoVariant,
     ModelType,
-    ModelVariantType,
+    SchedulerPredictionType,
     SubModelType,
 )
 from invokeai.backend.model_manager.config import CheckpointConfigBase, MainCheckpointConfig
@@ -68,27 +65,31 @@ class StableDiffusionDiffusersModel(GenericDiffusersLoader):
 
     def _convert_model(self, config: AnyModelConfig, model_path: Path, output_path: Path) -> Path:
         assert isinstance(config, MainCheckpointConfig)
-        variant = config.variant
         base = config.base
-        pipeline_class = (
-            StableDiffusionInpaintPipeline if variant == ModelVariantType.Inpaint else StableDiffusionPipeline
-        )
 
         config_file = config.config_path
+        prediction_type = config.prediction_type.value
+        upcast_attention = config.upcast_attention
+        image_size = (
+            1024
+            if base == BaseModelType.StableDiffusionXL
+            else 768
+            if config.prediction_type == SchedulerPredictionType.VPrediction and base == BaseModelType.StableDiffusion2
+            else 512
+        )
 
         self._logger.info(f"Converting {model_path} to diffusers format")
         convert_ckpt_to_diffusers(
             model_path,
             output_path,
             model_type=self.model_base_to_model_type[base],
-            model_version=base,
-            model_variant=variant,
             original_config_file=self._app_config.root_path / config_file,
             extract_ema=True,
-            scan_needed=True,
-            pipeline_class=pipeline_class,
             from_safetensors=model_path.suffix == ".safetensors",
             precision=self._torch_dtype,
+            prediction_type=prediction_type,
+            image_size=image_size,
+            upcast_attention=upcast_attention,
             load_safety_checker=False,
         )
         return output_path

invokeai/backend/model_manager/load/model_loaders/vae.py

@@ -57,12 +57,12 @@ class VAELoader(GenericDiffusersLoader):
 
         ckpt_config = OmegaConf.load(self._app_config.root_path / config_file)
         assert isinstance(ckpt_config, DictConfig)
-
+        self._logger.info(f"Converting {model_path} to diffusers format")
         vae_model = convert_ldm_vae_to_diffusers(
             checkpoint=checkpoint,
             vae_config=ckpt_config,
             image_size=512,
+            precision=self._torch_dtype,
         )
-        vae_model.to(self._torch_dtype)  # set precision appropriately
         vae_model.save_pretrained(output_path, safe_serialization=True)
         return output_path

invokeai/backend/model_manager/probe.py

@@ -319,7 +319,7 @@ class ModelProbe(object):
     @classmethod
     def _scan_and_load_checkpoint(cls, model_path: Path) -> CkptType:
         with SilenceWarnings():
-            if model_path.suffix.endswith((".ckpt", ".pt", ".bin")):
+            if model_path.suffix.endswith((".ckpt", ".pt", ".pth", ".bin")):
                 cls._scan_model(model_path.name, model_path)
                 model = torch.load(model_path)
                 assert isinstance(model, dict)