skills/feast-testing/SKILL.md
sdk/python/tests/
├── unit/ # Fast tests, no external deps, run locally
│ ├── infra/
│ │ ├── online_store/ # Per-store unit tests (redis, dynamodb, etc.)
│ │ ├── offline_stores/ # Offline store unit tests
│ │ └── registry/ # Registry unit tests
│ ├── test_unit_feature_store.py # Core FeatureStore behavior
│ ├── test_feature_views.py # Feature view validation
│ └── test_on_demand_*.py # On-demand transformation tests
└── integration/ # Requires real infrastructure (run in CI)
├── feature_repos/ # Sample repos used as test fixtures
└── test_universal_*.py # Cross-store compatibility tests
Rule of thumb: if a test needs mocks for an external service, it belongs in unit/.
If it spins up real infra (Redis, DynamoDB, BigQuery), it belongs in integration/.
# Run a single test file
python -m pytest sdk/python/tests/unit/infra/online_store/test_dynamodb_online_store.py -v
# Run a single test by name
python -m pytest sdk/python/tests/unit/test_unit_feature_store.py -k "test_apply" -v
# Run all unit tests for one subsystem
python -m pytest sdk/python/tests/unit/infra/online_store/ -v
# Run all unit tests (fast, no infra needed)
make test-python-unit
# Run local integration tests (SQLite online, file offline)
make test-python-integration-local
# Run specific integration test with verbose output
python -m pytest sdk/python/tests/integration/ -k "test_online_retrieval" -v -s
python -m pytest sdk/python/tests/unit/infra/online_store/test_redis.py -v --no-header -q
Follow sdk/python/tests/unit/infra/online_store/test_dynamodb_online_store.py or test_redis.py.
import asyncio
from unittest.mock import AsyncMock, MagicMock, patch
from feast.infra.online_stores.mystore import MyStore, MyStoreConfig
from feast.repo_config import RepoConfig
def make_config(store_config: dict) -> RepoConfig:
return RepoConfig(
project="test_project",
registry="data/registry.db",
provider="local",
online_store=store_config,
)
@patch("feast.infra.online_stores.mystore.MyClient")
def test_online_write_batch(mock_client_cls):
mock_client = MagicMock()
mock_client_cls.return_value = mock_client
config = make_config({"type": "mystore", "host": "localhost"})
store = MyStore()
feature_view = MagicMock()
feature_view.name = "driver_stats"
store.online_write_batch(config, feature_view, data=[...], progress=None)
mock_client.set.assert_called_once()
# For async methods:
def test_online_write_batch_async():
async def _run():
store = MyStore()
await store.online_write_batch_async(config, feature_view, data, progress=None)
asyncio.run(_run())
Follow sdk/python/tests/unit/infra/registry/test_registry.py.
from feast.infra.registry.registry import Registry
from feast.repo_config import RegistryConfig
def test_apply_feature_view(tmp_path):
config = RegistryConfig(path=str(tmp_path / "registry.db"))
registry = Registry("test_project", config, repo_path=None)
entity = Entity(name="driver_id", value_type=ValueType.INT64)
registry.apply_entity(entity, project="test_project")
stored = registry.get_entity("driver_id", project="test_project")
assert stored.name == "driver_id"
from feast import FeatureStore
from feast.repo_config import RepoConfig
def test_get_online_features(tmp_path):
config = RepoConfig(
project="test",
registry=str(tmp_path / "registry.db"),
provider="local",
online_store={"type": "sqlite", "path": str(tmp_path / "online.db")},
offline_store={"type": "file"},
)
store = FeatureStore(config=config)
# apply objects, write data, then assert retrieval
# Inspect the live registry
feast registry-dump # prints full proto as JSON
# Or from Python:
from feast import FeatureStore
store = FeatureStore(repo_path=".")
store.registry.list_feature_views(project=store.project)
store.registry.list_entities(project=store.project)
Symptom: FeatureView not found or stale feature definitions.
Fix: Re-run feast apply. If using a cached registry (TTL > 0), wait for cache expiry or force refresh by restarting the process.
# Check if materialization has run
feast feature-views list # shows last_updated_timestamp
# Check entity key format
# Entity keys are serialized — if the serialization_version doesn't match, lookups fail.
# Check entity_key_serialization_version in feature_store.yaml
Symptom: get_online_features returns all None values despite materialization running.
Cause: Entity key serialization version mismatch, wrong project name, or wrong TTL causing data to expire.
# Type-check only the file you changed
uv run bash -c "cd sdk/python && mypy feast/infra/online_stores/mystore.py"
# Common fix: add Optional[] around return types, use cast() for dynamic lookups
# Ensure you're running from repo root with dev dependencies installed
make install-python-dependencies-dev
# Run with uv to use the pinned venv
uv run python -m pytest sdk/python/tests/unit/... -v
Symptom: DecodeError or unexpected field values when reading registry.
Cause: Proto schema changed without recompiling.
Fix:
make compile-protos-python
# Start the feature server locally and check logs
feast serve --host 0.0.0.0 --port 6566
# Test directly
curl -X POST http://localhost:6566/get-online-features \
-H "Content-Type: application/json" \
-d '{"features": ["driver_stats:conv_rate"], "entities": {"driver_id": [1001]}}'
feast entities list # list all registered entities
feast feature-views list # list feature views + last materialization time
feast feature-services list # list feature services
feast on-demand-feature-views list # list ODFVs
feast registry-dump # dump full registry as JSON (debug)
feast plan # preview what feast apply would change (dry run)
| Utility | Location | Purpose |
|---|---|---|
get_feature_view() helpers | tests/unit/infra/online_store/test_*.py | Build minimal FeatureView mocks |
LocalRegistry fixture | tests/unit/infra/registry/test_registry.py | In-memory registry for unit tests |
integration/feature_repos/ | tests/integration/ | Sample repos for integration test scenarios |
conftest.py fixtures | Various tests/ subdirs | Shared pytest fixtures per subsystem |