Allow saving / loading from Huggingface Hub preset (keras-team#1510)

* first draft

* update upload_preset

* lint

* consistent error messages

* lint

keras_nlp/utils/preset_utils.py

@@ -27,8 +27,16 @@
 except ImportError:
     kagglehub = None
 
+try:
+    import huggingface_hub
+    from huggingface_hub.utils import HFValidationError
+except ImportError:
+    huggingface_hub = None
+
 KAGGLE_PREFIX = "kaggle://"
 GS_PREFIX = "gs://"
+HF_PREFIX = "hf://"
+
 TOKENIZER_ASSET_DIR = "assets/tokenizer"
 CONFIG_FILE = "config.json"
 TOKENIZER_CONFIG_FILE = "tokenizer.json"
@@ -69,15 +77,33 @@ def get_file(preset, path):
             url,
             cache_subdir=os.path.join("models", subdir),
         )
+    elif preset.startswith(HF_PREFIX):
+        if huggingface_hub is None:
+            raise ImportError(
+                f"`from_preset()` requires the `huggingface_hub` package to load from '{preset}'. "
+                "Please install with `pip install huggingface_hub`."
+            )
+        hf_handle = preset.removeprefix(HF_PREFIX)
+        try:
+            return huggingface_hub.hf_hub_download(
+                repo_id=hf_handle, filename=path
+            )
+        except HFValidationError as e:
+            raise ValueError(
+                "Unexpected Hugging Face preset. Hugging Face model handles "
+                "should have the form 'hf://{org}/{model}'. For example, "
+                f"'hf://username/bert_base_en'. Received: preset={preset}."
+            ) from e
     elif os.path.exists(preset):
         # Assume a local filepath.
         return os.path.join(preset, path)
     else:
         raise ValueError(
             "Unknown preset identifier. A preset must be a one of:\n"
-            "1) a built in preset identifier like `'bert_base_en'`\n"
+            "1) a built-in preset identifier like `'bert_base_en'`\n"
             "2) a Kaggle Models handle like `'kaggle://keras/bert/keras/bert_base_en'`\n"
-            "3) a path to a local preset directory like `'./bert_base_en`\n"
+            "3) a Hugging Face handle like `'hf://username/bert_base_en'`\n"
+            "4) a path to a local preset directory like `'./bert_base_en`\n"
             "Use `print(cls.presets.keys())` to view all built-in presets for "
             "API symbol `cls`.\n"
             f"Received: preset='{preset}'"
@@ -245,7 +271,9 @@ def upload_preset(
         uri: The URI identifying model to upload to.
              URIs with format
              `kaggle://<KAGGLE_USERNAME>/<MODEL>/<FRAMEWORK>/<VARIATION>`
-             will be uploaded to Kaggle Hub.
+             will be uploaded to Kaggle Hub while URIs with format
+             `hf://[<HF_USERNAME>/]<MODEL>` will be uploaded to the Hugging
+             Face Hub.
         preset: The path to the local model preset directory.
         allow_incomplete: If True, allows the upload of presets without
                           a tokenizer configuration. Otherwise, a tokenizer
@@ -262,10 +290,33 @@ def upload_preset(
     if uri.startswith(KAGGLE_PREFIX):
         kaggle_handle = uri.removeprefix(KAGGLE_PREFIX)
         kagglehub.model_upload(kaggle_handle, preset)
+    elif uri.startswith(HF_PREFIX):
+        if huggingface_hub is None:
+            raise ImportError(
+                f"`upload_preset()` requires the `huggingface_hub` package to upload to '{uri}'. "
+                "Please install with `pip install huggingface_hub`."
+            )
+        hf_handle = uri.removeprefix(HF_PREFIX)
+        try:
+            repo_url = huggingface_hub.create_repo(
+                repo_id=hf_handle, exist_ok=True
+            )
+        except HFValidationError as e:
+            raise ValueError(
+                "Unexpected Hugging Face URI. Hugging Face model handles "
+                "should have the form 'hf://[{org}/]{model}'. For example, "
+                "'hf://username/bert_base_en' or 'hf://bert_case_en' to implicitly"
+                f"upload to your user account. Received: URI={uri}."
+            ) from e
+        huggingface_hub.upload_folder(
+            repo_id=repo_url.repo_id, folder_path=preset
+        )
     else:
         raise ValueError(
-            f"Unexpected URI `'{uri}'`. Kaggle upload format should follow "
-            "`kaggle://<KAGGLE_USERNAME>/<MODEL>/<FRAMEWORK>/<VARIATION>`."
+            "Unknown URI. An URI must be a one of:\n"
+            "1) a Kaggle Model handle like `'kaggle://<KAGGLE_USERNAME>/<MODEL>/<FRAMEWORK>/<VARIATION>'`\n"
+            "2) a Hugging Face handle like `'hf://[<HF_USERNAME>/]<MODEL>'`\n"
+            f"Received: uri='{uri}'."
         )