Run Umbraco UI

Run Umbraco.UI (UUI)

UUI is a Lit web-component library (@umbraco-ui/uui). Its interactive surface is Storybook (a web app on http://localhost:6006). You drive it with a Playwright script — .claude/skills/run-umbraco-ui/driver.mjs — that opens a story and screenshots it. Playwright is already a project dependency, so no extra runtime is needed.

All paths below are relative to the repo root. Verified on macOS (Node 24, npm 11); commands are OS-agnostic.

Prerequisites

npm install
npx playwright install chromium   # browser binary; npm install does NOT fetch it

On a headless Linux container also run npx playwright install-deps chromium for the system libs (not needed on macOS).

Build (optional — only to produce the dist library)

Storybook does not need a prior build. Build only when verifying the published artifact:

npm run build      # web-component analyze → Vite lib build → tsc d.ts ; outputs dist/index.js, dist/index.d.ts

Run (agent path) — drive Storybook + screenshot

1. Start Storybook in the background (long-running; leave it up). Use your harness's own background mechanism — do not append & inside a backgrounded wrapper (it detaches and gets killed):

npm run storybook   # runs `analyze` then `storybook dev -p 6006`

Wait until it's reachable (cold start ~1–2 min for the analyze step; warm ~5 s):

until [ "$(curl -s -o /dev/null -w '%{http_code}' http://localhost:6006)" = 200 ]; do sleep 5; done

2. Drive it with the Playwright driver. It waits for the server, opens a story, optionally opens an addon panel, screenshots, and reports console errors (exit ≠ 0 if any):

# Isolated component canvas (best for component screenshots):
node .claude/skills/run-umbraco-ui/driver.mjs --story=uui-button--looks-and-colors --iframe --out=shot.png

# Full Storybook manager with an addon panel open (e.g. the README panel):
node .claude/skills/run-umbraco-ui/driver.mjs --story=uui-button--default --panel=Readme --out=shot.png

Options: --story=<id> (default uui-button--default), --iframe (component canvas only), --panel=<tab> (e.g. Readme, Controls; manager mode only), --out=<path>, --url=<base>, --timeout=<ms>. Then look at shot.png — a healthy run prints console/page errors: 0.

Story ids are <kebab-component>--<kebab-story>, e.g. uui-button--default, uui-button--looks-and-colors. Browse the sidebar in manager mode to discover them; docs pages use --docs.

Run (human path)

npm run storybook then open http://localhost:6006 in a browser. Useless headless — use the driver above instead.

Gotchas

• npm run storybook is analyze + storybook dev. The analyze step (Web Component Analyzer over 96 files) prints alarming !!!!!!! WARNING !!!!!!! banners about custom-elements.json being "experimental" — these are normal, not failures.
• Cold vs warm start. First launch waits on the analyze step (~1–2 min). A rebuild within the same checkout is cached and ready in ~5 s.
• The driver does not start Storybook — it only polls for it. Start Storybook first, or the driver fails fast with "Storybook not reachable… is npm run storybook running?".
• Two screenshot modes matter. --iframe hits /iframe.html?id=… and captures just the rendered component (clean shots). Without it you get the full manager UI (sidebar + canvas + addon panels) — needed when you want --panel.
• Components are in shadow DOM. Playwright's getByRole/getByText pierce shadow roots (the driver's --panel click relies on this); raw CSS selectors won't cross shadow boundaries.
• Background-process trap: launching npm run storybook with a trailing & inside an already-backgrounded shell detaches it and it gets reaped when the wrapper returns. Launch it directly via the background mechanism instead.

Troubleshooting

• Storybook not reachable at http://localhost:6006 after 120000ms → Storybook isn't up. Start npm run storybook, wait for the Storybook ready! banner / a 200 on :6006.
• browserType.launch: Executable doesn't exist → run npx playwright install chromium.
• Driver exits 1 → it found console/page errors and printed the first 10. Inspect them; a clean component renders with 0.

Tests

The project's test suite is npm run test (Vitest browser tests in Chromium). Not exercised by this skill; some WebKit/email-validation tests are known-flaky.