Migrate/minio to boto3

.github/workflows/test.yml

@@ -113,9 +113,7 @@ jobs:
       if: matrix.os == 'ubuntu-latest'
       id: clone-services
       run: |
-        # 2026-11-05: Services switched to SeaweedFS and the MinIO client cannot handle the new URLs.
-        # We use the old stack until we have migrated away from the MinIO client
-        git clone --revision dd8b98a9e0450bf487f973e1711c8b00dc022294 --depth 1 https://github.com/openml/services.git
+        git clone --revision a411948cb41d9d9fd99099e103d7b6871138abf4 --depth 1 https://github.com/openml/services.git
 
     - name: Start Docker Services
       id: start-services

.pre-commit-config.yaml

@@ -15,6 +15,7 @@ repos:
         additional_dependencies:
           - types-requests
           - types-python-dateutil
+          - boto3-stubs[s3]
   - repo: https://github.com/python-jsonschema/check-jsonschema
     rev: 0.38.2
     hooks:

openml/_api/__init__.py

@@ -1,7 +1,7 @@
 from .clients import (
     HTTPCache,
     HTTPClient,
-    MinIOClient,
+    S3Client,
 )
 from .resources import (
     API_REGISTRY,
@@ -65,13 +65,13 @@
     "FlowV2API",
     "HTTPCache",
     "HTTPClient",
-    "MinIOClient",
     "ResourceAPI",
     "ResourceV1API",
     "ResourceV2API",
     "RunAPI",
     "RunV1API",
     "RunV2API",
+    "S3Client",
     "SetupAPI",
     "SetupV1API",
     "SetupV2API",

openml/_api/clients/__init__.py

@@ -1,8 +1,8 @@
 from .http import HTTPCache, HTTPClient
-from .minio import MinIOClient
+from .s3 import S3Client
 
 __all__ = [
     "HTTPCache",
     "HTTPClient",
-    "MinIOClient",
+    "S3Client",
 ]