feat: add hf_login util

This provides a simple way to provide a HF token. If HF reports no valid token, one is prompted for until a valid token is provided, or the user presses Ctrl + C to cancel.

invokeai/app/util/hf_login.py

@@ -0,0 +1,46 @@
+import huggingface_hub
+from pwinput import pwinput
+
+from invokeai.app.util.suppress_output import SuppressOutput
+
+
+def hf_login() -> None:
+    """Prompts the user for their HuggingFace token. If a valid token is already saved, this function will do nothing.
+
+    Returns:
+        bool: True if the login was successful, False if the user canceled.
+
+    Raises:
+        RuntimeError: If the user cancels the login prompt.
+    """
+
+    current_token = huggingface_hub.get_token()
+
+    try:
+        if huggingface_hub.get_token_permission(current_token):
+            # We have a valid token already
+            return
+    except ConnectionError:
+        print("Unable to reach HF to verify token. Skipping...")
+        # No internet connection, so we can't check the token
+        pass
+
+    # InvokeAILogger depends on the config, and this class is used within the config, so we can't use the app logger here
+    print("Enter your HuggingFace token. This is required to convert checkpoint/safetensors models to diffusers.")
+    print("For more information, see https://huggingface.co/docs/hub/security-tokens#how-to-manage-user-access-tokens")
+    print("Press Ctrl+C to skip.")
+
+    while True:
+        try:
+            access_token = pwinput(prompt="HF token: ")
+            # The login function prints to stdout
+            with SuppressOutput():
+                huggingface_hub.login(token=access_token, add_to_git_credential=False)
+            print("Token verified.")
+            break
+        except ValueError:
+            print("Invalid token!")
+            continue
+        except KeyboardInterrupt:
+            print("\nToken verification canceled.")
+            break