diffusers: work more better with more models.

fixed relative path problem with local models.

fixed models on hub not always having a `fp16` branch.

ldm/invoke/model_cache.py

@@ -21,6 +21,8 @@ from typing import Union
 
 import torch
 import transformers
+from huggingface_hub import hf_hub_download
+from huggingface_hub.utils import RevisionNotFoundError
 from omegaconf import OmegaConf
 from omegaconf.errors import ConfigAttributeError
 from picklescan.scanner import scan_file_path
@@ -323,6 +325,8 @@ class ModelCache(object):
             # model_hash = huggingface_hub.get_hf_file_metadata(url).commit_hash
         elif 'path' in mconfig:
             name_or_path = Path(mconfig['path'])
+            if not name_or_path.is_absolute():
+                name_or_path = Path(Globals.root, name_or_path).resolve()
             # FIXME: What should the model_hash be? A hash of the unet weights? Of all files of all
             #     the submodels hashed together? The commit ID from the repo?
             model_hash = "FIXME TOO"
@@ -335,7 +339,16 @@ class ModelCache(object):
 
         if self.precision == 'float16':
             print('   | Using faster float16 precision')
-            pipeline_args.update(revision="fp16", torch_dtype=torch.float16)
+
+            if not isinstance(name_or_path, Path):
+                try:
+                    hf_hub_download(name_or_path, "model_index.json", revision="fp16")
+                except RevisionNotFoundError as e:
+                    pass
+                else:
+                    pipeline_args.update(revision="fp16")
+
+            pipeline_args.update(torch_dtype=torch.float16)
         else:
             # TODO: more accurately, "using the model's default precision."
             #     How do we find out what that is?
@@ -363,7 +376,10 @@ class ModelCache(object):
         if 'repo_name' in mconfig:
             return mconfig['repo_name']
         elif 'path' in mconfig:
-            return Path(mconfig['path'])
+            path = Path(mconfig['path'])
+            if not path.is_absolute():
+                path = Path(Globals.root, path).resolve()
+            return path
         else:
             raise ValueError("Model config must specify either repo_name or path.")