ark-chainsaw-testing
Testing & QualityRun and write Ark Chainsaw tests with mock-llm. Use for running tests, debugging failures, or creating new e2e tests.
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Ark Chainsaw Testing
Run and write Chainsaw e2e tests for Ark resources.
Running Tests
# Run all standard tests
(cd tests && chainsaw test --selector 'standard')
# Run specific test
chainsaw test ./tests/query-parameter-ref --fail-fast
# Debug mode - keep resources on failure
chainsaw test ./tests/query-parameter-ref --skip-delete --pause-on-failure
Writing Tests
Reference tests/CLAUDE.md for comprehensive patterns.
For a complete working example that shows the correct patterns for writing tests, see examples.md.
Test Structure
tests/my-test/
├── chainsaw-test.yaml # Test definition
├── mock-llm-values.yaml # Mock LLM config (if needed)
├── README.md # Required documentation
└── manifests/
├── a03-model.yaml # Model before Agent
├── a04-agent.yaml # Agent before Query
└── a05-query.yaml # Query last
Antipatterns
kubectl wait for CRD conditions
Never use kubectl wait --for=condition=Established to check CRD readiness. This command crashes with a type error when .status.conditions is nil (a known kubectl bug: kubernetes/kubernetes#66439):
error: .status.conditions accessor error: <nil> is of the type <nil>, expected []interface{}
Use a chainsaw assert with JMESPath instead — it polls gracefully and waits for the field to appear:
# Bad - crashes if .status.conditions is nil
- script:
content: |
kubectl apply -f my-crd.yaml
kubectl wait --for=condition=Established crd/my-crd.example.com --timeout=60s
# Good - polls until condition appears, no nil crash
- script:
content: |
kubectl apply -f my-crd.yaml
- assert:
resource:
apiVersion: apiextensions.k8s.io/v1
kind: CustomResourceDefinition
metadata:
name: my-crd.example.com
status:
(conditions[?type == 'Established']):
- status: "True"
This pattern converts a brittle timeout into an explicit condition check. The same applies to any resource whose .status.conditions may start as nil.
assert instead of wait for Query completion
Never use assert to wait for a Query to complete. assert polls the API server repeatedly; wait uses a Kubernetes watch (event-driven), which is faster and cheaper:
# Bad - polls every few seconds, hammers the API server
- assert:
resource:
apiVersion: ark.mckinsey.com/v1alpha1
kind: Query
metadata:
name: test-query
status:
phase: done
# Good - uses a watch, fires once the condition is set
- wait:
apiVersion: ark.mckinsey.com/v1alpha1
kind: Query
name: test-query
timeout: 4m
for:
condition:
name: Completed
value: 'True'
Use assert only after wait has confirmed the query is done — i.e., for post-completion validation of response fields. Keep these as separate steps so timing is explicit:
- name: wait-for-query-completion
try:
- wait:
apiVersion: ark.mckinsey.com/v1alpha1
kind: Query
name: test-query
timeout: 4m
for:
condition:
name: Completed
value: 'True'
- name: validate-response
try:
- assert:
resource:
apiVersion: ark.mckinsey.com/v1alpha1
kind: Query
metadata:
name: test-query
status:
(response != null): true
phase: done
Shell scripts for condition checking
Avoid using shell scripts with kubectl get + jq to validate resource state when chainsaw assertions can express the check declaratively. Shell scripts fail immediately on unexpected nil values; assertions retry until the condition is met or the timeout expires.
# Bad - fails immediately if field is absent
- script:
content: |
val=$(kubectl get myresource foo -o jsonpath='{.status.phase}')
[ "$val" = "Ready" ] || exit 1
# Good - retries until condition is true
- assert:
resource:
apiVersion: example.com/v1
kind: MyResource
metadata:
name: foo
status:
phase: Ready
Environment Variables
For real LLM tests (not mock-llm):
export E2E_TEST_AZURE_OPENAI_KEY="your-key"
export E2E_TEST_AZURE_OPENAI_BASE_URL="your-endpoint"