ci: harden Lighthouse budget execution

.github/actions/setup-lighthouse-chromium/action.yml

@@ -1,7 +1,8 @@
 name: Setup pinned Chromium for Lighthouse
 description: >
- Install Playwright's managed Chromium and export PLAYWRIGHT_CHROMIUM_EXECUTABLE_PATH, so every
- Lighthouse job in this repository measures with the same browser build for a given commit.
+ Install Playwright's managed Chromium and export CHROME_PATH plus
+ PLAYWRIGHT_CHROMIUM_EXECUTABLE_PATH, so every Lighthouse job in this repository measures with the
+ same browser build for a given commit.
 
 # The Lighthouse budget used to drive whatever Chrome ships in the ubuntu-24.04 runner image
 # (matching live-web-vitals.yml, which measures a live domain and isn't graded against a
@@ -46,4 +47,9 @@ runs:
 
  - name: Pin the Chromium executable path
  shell: bash
- run: echo "PLAYWRIGHT_CHROMIUM_EXECUTABLE_PATH=$(node -e "console.log(require('playwright').chromium.executablePath())")" >> "$GITHUB_ENV"
+ run: |
+ chromium_path="$(node -e "console.log(require('playwright').chromium.executablePath())")"
+ {
+ echo "CHROME_PATH=$chromium_path"
+ echo "PLAYWRIGHT_CHROMIUM_EXECUTABLE_PATH=$chromium_path"
+ } >> "$GITHUB_ENV"

.github/workflows/ci.yml

@@ -851,7 +851,7 @@ jobs:
  - name: Show the baseline diff and the browser it was measured on
  run: |
  git --no-pager diff --stat -- lighthouse-budget.json
- node -e "const b=require('./lighthouse-budget.json');console.log([...new Set(Object.values(b.baseline??{}).map(r=>r.chromeVersion))].join('\n'))"
+ node -e "const b=require('./lighthouse-budget.json');const versions=[...new Set(Object.values(b.baseline??{}).map(r=>r.chromeVersion).filter(v=>typeof v==='string'&&v.length>0))];console.log(versions.join('\n'));if(versions.length!==1){console.error('Expected exactly one baseline Chrome version; found '+versions.length+'.');process.exit(1)}"
 
  - name: Upload the refreshed baseline
  if: always()

.github/workflows/live-web-vitals.yml

@@ -56,7 +56,7 @@ jobs:
  measure:
  name: Lighthouse against the live domain
  runs-on: ubuntu-24.04
- timeout-minutes: 30
+ timeout-minutes: 45
  env:
  # Repository variable overrides the default (e.g. a staging cutover),
  # matching live-domain-monitor.yml.
@@ -99,26 +99,13 @@ jobs:
  echo "LIVE_DOMAIN_URL=$normalized" >> "$GITHUB_ENV"
  echo "origin -> $normalized"
 
- - name: Reject a sample count too small to grade
+ - name: Validate the bounded target matrix
  run: |
  set -euo pipefail
- # `samples` is a free-text dispatch input, so `samples=1` is accepted
- # by the form and would produce one report per cell — a "median" of
- # one, a zero-width range, and a straddle check that can never fire.
- # The summariser refuses the same count, but refusing HERE means the
- # operator finds out in seconds instead of after a full measurement
- # pass against the live domain.
- case "$SAMPLES" in
- ''|*[!0-9]*)
- echo "::error::samples must be a positive integer, got '$SAMPLES'"
- exit 1
- ;;
- esac
- if [ "$SAMPLES" -lt 3 ]; then
- echo "::error::samples=$SAMPLES cannot be graded — #017 needs at least 3 runs per cell so a median has dispersion behind it"
- exit 1
- fi
- echo "samples -> $SAMPLES per route/strategy"
+ # Dispatch inputs are free text. Validate route identity, collision-free
+ # artifact names, the minimum sample count, and the capped total before
+ # this workflow makes any request to the live origin.
+ node scripts/live-web-vitals-inputs.mjs "$LIVE_DOMAIN_URL" "$ROUTES" "$SAMPLES"
 
  - name: Confirm the target is reachable before spending a Lighthouse run
  run: |
@@ -135,26 +122,38 @@ jobs:
  set -euo pipefail
  mkdir -p web-vitals
  IFS=',' read -ra route_list <<< "$ROUTES"
+ suite_deadline=$((SECONDS + LIVE_WEB_VITALS_MEASUREMENT_SUITE_SECONDS))
+ suite_expired=0
  for strategy in mobile desktop; do
+ if [ "$suite_expired" -eq 1 ]; then break; fi
  for route in "${route_list[@]}"; do
+ if [ "$suite_expired" -eq 1 ]; then break; fi
  route="$(echo "$route" | xargs)"
  [ -n "$route" ] || continue
  # Filename-safe slug: "/" -> root, "/a/b" -> a-b
  slug="$(echo "$route" | sed 's|^/||; s|/|-|g')"
  [ -n "$slug" ] || slug="root"
  for sample in $(seq 1 "$SAMPLES"); do
- out="web-vitals/${strategy}-${slug}-${sample}"
- echo "::group::$strategy $route (sample $sample/$SAMPLES)"
- # One flaky route must not discard the whole run, so a failure is
- # a warning here; the summary step fails if NOTHING was produced.
- npx --yes "lighthouse@$LIGHTHOUSE_VERSION" "$LIVE_DOMAIN_URL$route" \
- --output=json --output-path="${out}.json" \
- --preset="$([ "$strategy" = desktop ] && echo desktop || echo perf)" \
- --only-categories=performance \
- --chrome-flags="--headless=new --no-sandbox --disable-dev-shm-usage" \
- --max-wait-for-load=60000 \
- --quiet || echo "::warning::lighthouse failed for $strategy $route sample $sample"
- echo "::endgroup::"
+ remaining=$((suite_deadline - SECONDS))
+ if [ "$remaining" -le 0 ]; then
+ echo "::warning::live web vitals measurement suite deadline expired; skipping remaining cells"
+ suite_expired=1
+ break
+ fi
+ run_timeout="$LIVE_WEB_VITALS_PROCESS_TIMEOUT_SEC"
+ if [ "$remaining" -lt "$run_timeout" ]; then run_timeout="$remaining"; fi
+ out="web-vitals/${strategy}-${slug}-${sample}"
+ echo "::group::$strategy $route (sample $sample/$SAMPLES)"
+ # One flaky route must not discard the whole run, so a failure is
+ # a warning here; the summary step fails if NOTHING was produced.
+ timeout --signal=TERM --kill-after=10s "${run_timeout}s" npx --yes "lighthouse@$LIGHTHOUSE_VERSION" "$LIVE_DOMAIN_URL$route" \
+ --output=json --output-path="${out}.json" \
+ --preset="$([ "$strategy" = desktop ] && echo desktop || echo perf)" \
+ --only-categories=performance \
+ --chrome-flags="--headless=new --no-sandbox --disable-dev-shm-usage" \
+ --max-wait-for-load=60000 \
+ --quiet || echo "::warning::lighthouse failed for $strategy $route sample $sample"
+ echo "::endgroup::"
  done
  done
  done