From 5834aaa5ceba8caa562842b45e91ab9acf2c4e42 Mon Sep 17 00:00:00 2001
From: Omswastik-11 <omswastikpanda11@gmail.com>
Date: Mon, 29 Dec 2025 17:14:35 +0530
Subject: [PATCH] add openmlauthentication Error exception

---
 openml/_api_calls.py                | 10 +++-------
 openml/exceptions.py                | 23 +++++++++++++++++++++++
 tests/test_openml/test_api_calls.py |  2 +-
 3 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/openml/_api_calls.py b/openml/_api_calls.py
index 81296b3da..f0c0941de 100644
--- a/openml/_api_calls.py
+++ b/openml/_api_calls.py
@@ -23,8 +23,8 @@
 from . import config
 from .__version__ import __version__
 from .exceptions import (
+    OpenMLAuthenticationError,
     OpenMLHashException,
-    OpenMLNotAuthorizedError,
     OpenMLServerError,
     OpenMLServerException,
     OpenMLServerNoResult,
@@ -516,11 +516,7 @@ def __parse_server_exception(
         400,  # run/42 delete
         460,  # task/42 delete
     ]:
-        msg = (
-            f"The API call {url} requires authentication via an API key.\nPlease configure "
-            "OpenML-Python to use your API as described in this example:"
-            "\nhttps://openml.github.io/openml-python/latest/examples/Basics/introduction_tutorial/#authentication"
-        )
-        return OpenMLNotAuthorizedError(message=msg)
+        msg = f"The API call {url} requires authentication via an API key."
+        return OpenMLAuthenticationError(message=msg)
 
     return OpenMLServerException(code=code, message=full_message, url=url)
diff --git a/openml/exceptions.py b/openml/exceptions.py
index fe63b8a58..1c1343ff3 100644
--- a/openml/exceptions.py
+++ b/openml/exceptions.py
@@ -63,5 +63,28 @@ class OpenMLNotAuthorizedError(OpenMLServerError):
     """Indicates an authenticated user is not authorized to execute the requested action."""
 
 
+class OpenMLAuthenticationError(OpenMLServerError):
+    """Exception raised when API authentication fails.
+
+    This typically occurs when:
+    - No API key is configured
+    - The API key is invalid or expired
+    - The API key format is incorrect
+
+    This is different from authorization (OpenMLNotAuthorizedError), which occurs
+    when a valid API key lacks permissions for the requested operation.
+    """
+
+    def __init__(self, message: str):
+        help_text = (
+            "\n\nTo fix this:\n"
+            "1. Get your API key from https://www.openml.org/\n"
+            "   (you'll need to register for a free account if you don't have one)\n"
+            "2. Configure your API key by following the authentication guide:\n"
+            "   https://openml.github.io/openml-python/latest/examples/Basics/introduction_tutorial/#authentication"
+        )
+        super().__init__(message + help_text)
+
+
 class ObjectNotPublishedError(PyOpenMLError):
     """Indicates an object has not been published yet."""
diff --git a/tests/test_openml/test_api_calls.py b/tests/test_openml/test_api_calls.py
index da6857b6e..d5bd3a72c 100644
--- a/tests/test_openml/test_api_calls.py
+++ b/tests/test_openml/test_api_calls.py
@@ -121,5 +121,5 @@ def test_authentication_endpoints_requiring_api_key_show_relevant_help_link(
 ) -> None:
     # We need to temporarily disable the API key to test the error message
     with openml.config.overwrite_config_context({"apikey": None}):
-        with pytest.raises(openml.exceptions.OpenMLNotAuthorizedError, match=API_TOKEN_HELP_LINK):
+        with pytest.raises(openml.exceptions.OpenMLAuthenticationError, match=API_TOKEN_HELP_LINK):
             openml._api_calls._perform_api_call(call=endpoint, request_method=method, data=None)