Hold MLOps artifacts in Snowflake stages and score registry versions with run_batch

examples/mlops/snowflake/README.md

@@ -15,7 +15,10 @@ generates is undocumented) and has not been run end to end; see
   Tracking through the connector's Snowpark session.
 - **`KUMO_SCORE`** (`KUMO_SCORE_TASK`, daily 03:00 UTC) runs `score_job.py`,
   loading the version `champion` points at and writing
-  `USERS_CHURN_PREDICTIONS`.
+  `USERS_CHURN_PREDICTIONS`. It scores with `Trainer.predict`, so each run is
+  a Kumo prediction run under the artifact root that `evaluate` and
+  `score_drift` read; a native `run_batch` job on the version writes scores
+  only.
 
 To review a model before scoring, drop the alias from the registry location
 in `jobs.mlops` and move `champion` yourself

examples/mlops/snowflake/run_batch_smoke.py

@@ -0,0 +1,131 @@
+# SPDX-FileCopyrightText: Copyright (c) 2026, NVIDIA CORPORATION & AFFILIATES.
+# All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+"""Live smoke: register a model with a stage snapshot and score it with run_batch.
+
+run_batch writes scores only: no Kumo prediction run for evaluate or
+score_drift. See "Batch inference in Snowflake" in
+packages/kumo-engine/docs/mlops.md.
+
+    python run_batch_smoke.py --connection-name <connections.toml entry> \\
+        --warehouse WH --database ML --schema MODELS \\
+        --stage @ML.MODELS.KUMO --compute-pool KUMO_GPU_POOL
+"""
+
+import argparse
+import tempfile
+from pathlib import Path
+
+import numpy as np
+import pandas as pd
+from kumoapi.graph import Edge
+from kumoapi.model_plan import ModelPlan
+from kumoapi.typing import Stype
+
+import kumo.engine as kumo
+
+
+def snapshot_and_query(data: Path) -> tuple:
+    rng = np.random.default_rng(0)
+    pd.DataFrame({'ID': np.arange(200)}).to_parquet(data / 'users.parquet')
+    pd.DataFrame({
+        'OID': np.arange(5000),
+        'USER_ID': rng.integers(0, 200, 5000),
+        'TS': pd.Timestamp('2024-01-01') +
+        pd.to_timedelta(rng.integers(0, 120, 5000), unit='D'),
+    }).to_parquet(data / 'orders.parquet')
+    files = kumo.FileConnector(root_dir=str(data))
+    graph = kumo.Graph(
+        tables={
+            'users':
+            kumo.Table.from_source_table(files['users.parquet'],
+                                         primary_key='ID').infer_metadata(),
+            'orders':
+            kumo.Table.from_source_table(
+                files['orders.parquet'], primary_key='OID',
+                time_column='TS').infer_metadata().with_column(
+                    'USER_ID', stype=Stype.ID),
+        }, edges=[Edge(src_table='orders', fkey='USER_ID', dst_table='users')])
+    snapshot = graph.snapshot()
+    query = kumo.PredictiveQuery(
+        graph=graph, query='PREDICT COUNT(orders.*, 0, 7, days) > 0 '
+        'FOR EACH users.ID')
+    return snapshot, query
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser(description=__doc__.split('\n\n')[0])
+    parser.add_argument('--connection-name', required=True)
+    parser.add_argument('--warehouse', required=True)
+    parser.add_argument('--database', required=True)
+    parser.add_argument('--schema', required=True)
+    parser.add_argument('--stage', required=True,
+                        help='named internal stage, @DB.SCHEMA.STAGE')
+    parser.add_argument('--compute-pool', required=True)
+    parser.add_argument('--model-name', default='KUMO_RUN_BATCH_SMOKE')
+    parser.add_argument('--pip-repository', default=None)
+    args = parser.parse_args()
+
+    from snowflake.ml.model.batch_inference import (
+        InferenceSpec,
+        InputSpec,
+        OutputSpec,
+        ResourcesSpec,
+        SaveMode,
+    )
+    from snowflake.ml.registry import Registry
+
+    sf = kumo.SnowflakeConnector.from_connection_toml(
+        connection_name=args.connection_name, warehouse=args.warehouse,
+        database=args.database, schema_name=args.schema)
+    stage = args.stage.rstrip('/')
+    with tempfile.TemporaryDirectory() as tmp:
+        snapshot, query = snapshot_and_query(Path(tmp))
+        exported = snapshot.export(
+            kumo.SnapshotOutputConfig(sf, f'{stage}/smoke/snapshots'))
+        trainer = kumo.Trainer(model_plan=ModelPlan())
+        result = trainer.fit(
+            query.generate_training_table(snapshot), snapshot=snapshot,
+            export_config=kumo.ModelOutputConfig(
+                sf, location=kumo.ModelRegistryLocation(args.model_name),
+                serving_snapshot=exported,
+                serving_options={'pip_repository': args.pip_repository}
+                if args.pip_repository else None))
+        published = result.published_model
+        print(f'registered {published.name} version {published.version}')
+
+        table = query.generate_prediction_table(snapshot)
+        time = pd.Timestamp(table.timestamps[0])
+        expected = trainer.predict(table, snapshot=snapshot,
+                                   binary_classification_threshold=0.5).frame
+
+    session = sf.session()
+    version = Registry(session, database_name=args.database,
+                       schema_name=args.schema).get_model(
+                           published.name).version(published.version)
+    rows = session.create_dataframe(
+        pd.DataFrame({'ENTITY': expected['ENTITY'].astype(str)}))
+    output = f'{stage}/smoke/scores/'
+    job = version.run_batch(
+        rows, compute_pool=args.compute_pool,
+        output_spec=OutputSpec(stage_location=output, mode=SaveMode.OVERWRITE),
+        input_spec=InputSpec(params={
+            'prediction_time': str(time),
+            'binary_classification_threshold': 0.5,
+        }), resources_spec=ResourcesSpec(gpu_requests='1'),
+        inference_spec=InferenceSpec(num_workers=1))
+    job.wait()
+    job_name = job.id.split('.')[-1].strip('"')
+    scored = session.read.parquet(f'{output}{job_name}/').to_pandas()
+    scored.columns = [column.strip('"') for column in scored.columns]
+
+    local = expected.assign(ENTITY=expected['ENTITY'].astype(str)).sort_values(
+        'ENTITY').reset_index(drop=True)
+    remote = scored[list(local.columns)].sort_values('ENTITY').reset_index(
+        drop=True)
+    pd.testing.assert_frame_equal(local, remote, check_dtype=False, atol=1e-5)
+    print(f'PASS: {len(remote)} rows match local scores')
+
+
+if __name__ == '__main__':
+    main()