Chart Tests Agent Skill

tests/
├── __init__.py               # supported_k8s_versions, newest/oldest_supported_kube_version, etc.
├── chart/                    # Helm template rendering tests (main focus)
│   ├── test_<component>.py   # One file per component
│   ├── conftest.py           # Shared fixtures (helm dep upgrade, docker client, node-pool config)
│   ├── __init__.py           # get_service_ports_by_name(), get_all_features()
│   └── test_data/            # Feature configs, expected outputs (e.g. auth-sidecar nginx confs)
├── functional/               # End-to-end cluster tests (testinfra) — see functional-tests skill
├── k8s_schema/               # Cached Kubernetes API schemas (v<version>-standalone/)
├── enable_all_features.yaml  # Values dict loaded by get_all_features()
└── utils/
    ├── chart.py              # render_chart() and k8s schema validation
    └── __init__.py           # get_containers_by_name(), get_all_features(), get_env_vars_dict(), get_pod_template()

import pytest
from tests import supported_k8s_versions
from tests.utils.chart import render_chart

DEPLOYMENT_FILE = "templates/dag-deploy/dag-server-statefulset.yaml"


@pytest.mark.parametrize("kube_version", supported_k8s_versions)
def test_some_feature(kube_version):
    """Brief description of what is being tested."""
    docs = render_chart(
        kube_version=kube_version,
        show_only=[DEPLOYMENT_FILE],
        values={"dagDeploy": {"enabled": True}},
    )
    assert len(docs) == 1
    assert docs[0]["kind"] == "StatefulSet"

values = {"dagDeploy": {"enabled": True}}
values = {"gitSyncRelay": {"enabled": True, "repo": {"url": "..."}}}
values = {"authSidecar": {"enabled": True}}

# ❌ WRONG — will not override the airflow sub-chart's values
values = {"pgbouncer": {"enabled": True}}

# ✅ CORRECT — nest under the `airflow` sub-chart key
values = {"airflow": {"pgbouncer": {"enabled": True}}}

# ✅ EXAMPLE — set the executor on the airflow sub-chart
docs = render_chart(
    values={"airflow": {"executor": "KubernetesExecutor"}},
    show_only=["charts/airflow/templates/scheduler/scheduler-deployment.yaml"],
)

docs = render_chart(
    show_only=[
        "templates/git-sync-relay/git-sync-relay-deployment.yaml",
        "templates/dag-deploy/dag-server-service.yaml",
    ]
)

@pytest.mark.parametrize("kube_version", supported_k8s_versions)
@pytest.mark.parametrize("enabled,docs_count", [(True, 1), (False, 0)])
def test_deployment_should_render(kube_version, enabled, docs_count):
    docs = render_chart(
        kube_version=kube_version,
        show_only=[DEPLOYMENT_FILE],
        values={"dagDeploy": {"enabled": enabled}},
    )
    assert len(docs) == docs_count

from tests.utils import get_all_features

def test_with_all_features():
    docs = render_chart(values=get_all_features())
    kinds = [doc["kind"] for doc in docs]
    assert "Deployment" in kinds

   # ✅ CORRECT
   apiVersion: v1
   kind: ConfigMap
   metadata:
     name: {{ include "chart.fullname" . }}-scripts
   data:
     my-script.sh: {{ .Files.Get "files/my-script.sh" | quote }}

   # ❌ WRONG — inline script with template logic
   data:
     my-script.sh: |
       #!/bin/sh
       {{- if .Values.someFlag }}
       do_something
       {{- end }}

from tests.utils.chart import render_chart

docs = render_chart(
    values={"gitSyncRelay": {"enabled": True}},
    show_only=["templates/git-sync-relay/git-sync-relay-service.yaml"],
    kube_version="1.31.0",
)

from tests.utils import get_containers_by_name

c_by_name = get_containers_by_name(doc, include_init_containers=True)
assert c_by_name["scheduler"]["securityContext"]["readOnlyRootFilesystem"]
assert c_by_name["git-sync-relay"]["securityContext"]["readOnlyRootFilesystem"]

from tests.utils import get_all_features

# Canonical full run via the Makefile (runs helm dep update + venv setup first)
make unittest-chart

# Pass extra pytest options to the Makefile target
make unittest-chart PYTEST_ADDOPTS='-v --maxfail=1 -k "git-sync"'

# Full suite in parallel (fastest — use for full runs). These are equivalent:
uv run pytest tests/chart/ -n auto --quiet
.venv/bin/python -m pytest tests/chart/ -n auto --quiet
.venv/bin/pytest tests/chart/ -n auto --quiet

# Single file
uv run pytest tests/chart/test_git_sync_relay_deployment.py --verbose

# Tests matching a pattern
uv run pytest tests/chart/ -k "pgbouncer" --verbose

# Single test
uv run pytest tests/chart/test_default_chart.py::TestDefaultChart::test_default_labels --verbose

# Verbose output, stop on first failure
uv run pytest tests/chart/ -vv --capture=no --maxfail=1

# Iterate on failures: re-run only last-failed tests
uv run pytest tests/chart/ --maxfail=1 --lf

# ❌ WRONG — do not hand-roll a separate venv with pip. Use the repo's managed environment
# (make / uv / .venv) so dependencies match tests/requirements.txt and uv.lock.
python3 -m venv /tmp/myenv && /tmp/myenv/bin/pip install pytest && /tmp/myenv/bin/pytest tests/chart/

def test_statefulset_is_valid():
    docs = render_chart(
        values={"dagDeploy": {"enabled": True}},
        show_only=["templates/dag-deploy/dag-server-statefulset.yaml"],
        validate_objects=True,
    )
    assert docs[0]["kind"] == "StatefulSet"