NIC Testing Patterns

What it does

When your agent uses it

• Writing Go unit or table-driven tests for the NGINX Ingress Controller
• Changing an nginx template and updating its snapshot golden files
• Adding Helm chart tests for new chart values
• Writing pytest integration tests for the Ingress Controller
• Checking which make target runs tests, linting or coverage

Example prompts

• “I added a new directive to nginx.tmpl, so update the snapshot tests the right way.”
• “Write table-driven tests for the new policy handler in internal/configs.”
• “Add a Helm test case for the new value in values.yaml and regenerate the snapshots.”

Requirements

• Go toolchain and make
• Docker, for make lint
• Python with pytest, for the integration tests

Workflow steps

6 steps, taken from the first numbered list in SKILL.md.

1. 1Add or extend a test case first. Regenerating alone only re-records existing fixtures. If no fixture sets your new field, the golden file…
2. 2Run make test-update-snaps.
3. 3Inspect what actually changed
4. 4Read the diff and confirm your directive is present in the golden output for every edition that supports it. An empty diff after a .tmpl…
5. 5Run make test to confirm the suite is green against the regenerated files.
6. 6Commit the snapshots changes in the same commit as the template change.

What it can do on your machine

Read from SKILL.md and the folder at commit f6d0615. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  Shell commands in SKILL.md call:

  • make
  • git
  • go

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  No URLs in SKILL.md. Its commands use git, which can reach the network depending on how they are called.

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

NIC Testing Patterns loads about 2.8k tokens when it runs. Until then it costs about 65 tokens; SKILL.md has 1,061 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~65

When it runs · the whole SKILL.md, loaded when a task matches

~2.8k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from nginx/kubernetes-ingress at commit f6d0615, republished under its Apache-2.0 licence (© nginx). 1,061 words, ~2,802 tokens.

name

nic-testing

description

Testing patterns for NIC including Go table-driven tests, snapshot tests, and Python integration tests. Use when writing unit tests, snapshot tests, policy tests, template tests, Helm tests, or pytest integration tests for the Ingress Controller.

func TestValidateMyPolicy(t *testing.T) {
    t.Parallel()
    tests := []struct {
        policy *v1.Policy
        isPlus bool
        msg    string
    }{
        { /* valid case */ },
        { /* edge case */ },
    }
    for _, test := range tests {
        err := ValidatePolicy(test.policy, test.isPlus, false, false)
        if err != nil {
            t.Errorf("ValidatePolicy returned error %v for case: %s", err, test.msg)
        }
    }
}

func TestMain(m *testing.M) {
    snaps.Clean(m, snaps.CleanOpts{Sort: true})
}

func TestVirtualServerForNginx(t *testing.T) {
    t.Parallel()
    executor := newTmplExecutorNGINX(t)
    data, err := executor.ExecuteVirtualServerTemplate(&virtualServerCfg)
    require.NoError(t, err)
    snaps.MatchSnapshot(t, string(data))
}

@pytest.mark.policies
@pytest.mark.policies_myfeature
@pytest.mark.parametrize(
    "crd_ingress_controller, virtual_server_setup",
    [({"type": "complete", "extra_args": [...]},
      {"example": "virtual-server", "app_type": "simple"})],
    indirect=True,
)
class TestMyFeaturePolicies:
    def test_basic_functionality(self, kube_apis, crd_ingress_controller,
                                  virtual_server_setup, test_namespace):
        # 1. Create policy from YAML
        pol_name = create_policy_from_yaml(
            kube_apis.custom_objects, yaml_src, test_namespace
        )
        wait_before_test()
        # 2. Patch VS to reference policy
        patch_virtual_server_from_yaml(...)
        # 3. Assert HTTP responses
        resp = requests.get(url, headers={"host": vs_host})
        assert resp.status_code == 200
        assert "Expected-Header" in resp.headers
        # 4. Cleanup
        delete_policy(kube_apis.custom_objects, pol_name, test_namespace)
        patch_virtual_server_from_yaml(...)  # restore original

© nginx, Apache-2.0. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

Just SKILL.md in .github/skills/nic-testing of nginx/kubernetes-ingress.

Open the folder on GitHubat commit f6d0615