7.8 KiB
phase: 03-dashboard-intake-ui plan: "05" subsystem: ui, pwa tags: [react, typescript, pwa, service-worker, qr-scanner, zxing, camera]
Dependency graph
requires:
- web/src/store/ui.ts (useUIStore.setScannerActive)
- web/src/components/ui/button.tsx
- @zxing/browser (already in package.json from Plan 01) provides:
- web/public/manifest.json (PWA installable config)
- web/public/sw.js (app-shell service worker)
- web/public/icons/icon-192.png, icon-512.png (PWA icons)
- web/src/hooks/usePWA.ts (service worker registration hook)
- web/src/pages/ScanPage.tsx (/scan QR camera scanner)
- web/src/lib/api.ts (fetchInventory, fetchInventoryItem typed wrappers)
- web/src/components/layout/AppShell.tsx (page layout wrapper) affects:
- web/index.html (theme-color meta added)
- web/src/App.tsx (usePWA() call added)
- web/src/router.tsx (scanRoute lazy-loads ScanPage)
Tech tracking
tech-stack: added: [] patterns: - PWA app-shell cache strategy (navigation cache-first, API network-only, static assets cache-first) - @zxing/browser decodeFromVideoDevice for live camera QR scanning - lazy() + Suspense code-splitting for heavy QR scanner bundle (444KB chunk) - extractHWID() regex — strict pattern matching before any navigation
key-files: created: - web/public/manifest.json - web/public/sw.js - web/public/icons/icon-192.png - web/public/icons/icon-512.png - web/scripts/gen-icons.cjs - web/src/hooks/usePWA.ts - web/src/pages/ScanPage.tsx - web/src/lib/api.ts - web/src/components/layout/AppShell.tsx modified: - web/index.html (theme-color meta) - web/src/App.tsx (usePWA hook) - web/src/router.tsx (lazy ScanPage + Suspense)
decisions:
- id: PWA-D01 summary: "ScanPage code-split as separate lazy chunk (444KB) — @zxing/browser is large; lazy loading keeps initial bundle lean at 275KB"
- id: PWA-D02 summary: "api.ts and AppShell.tsx created as minimal stubs in this plan — Plans 03-03/03-04 run in parallel and hadn't built them yet; stubs provide exactly the interface ScanPage needs without duplicating plan scope"
- id: PWA-D03 summary: "Icon generation uses pure Node.js + zlib (no ImageMagick/canvas) — zero external tooling required; gen-icons.cjs is committed for reproducibility"
Metrics
duration: ~15min completed: 2026-04-10T06:22:00Z tasks_completed: 2 files_created: 9 files_modified: 3
Phase 3 Plan 05: PWA Manifest + Service Worker + QR Scanner Summary
PWA installable manifest with app-shell service worker, programmatically generated icons, and a live camera QR scanner at /scan that resolves HW-XXXXX labels to NetBox inventory items.
Performance
- Duration: ~15 min
- Started: 2026-04-10T06:07:00Z
- Completed: 2026-04-10T06:22:00Z
- Tasks: 2
- Files created: 9
- Files modified: 3
Accomplishments
web/public/manifest.json— PWA web app manifest:display=standalone,theme_color=#faff69,background_color=#000000, 192px + 512px icons, portrait-primary orientationweb/public/sw.js— App shell service worker with three-tier fetch strategy: API calls always network-only (no stale inventory), navigation requests cache-first (offline shell), static assets cache-first with network fallback and cache populationweb/public/icons/icon-192.png+icon-512.png— Valid PNG icons generated byweb/scripts/gen-icons.cjs(pure Node.js, no external deps): black canvas with volt#faff69H monogramweb/src/hooks/usePWA.ts— Service worker registration hook called fromApp.tsxon window loadweb/src/pages/ScanPage.tsx— Full camera QR scanner:- Rear camera preference (label matching:
back|rear|environment) - Volt corner-bracket reticle overlay on live viewfinder
extractHWID()regex matcheshttp://.../hw/HW-XXXXXURLs and bareHW-XXXXXIDslastScanneddebounce prevents duplicate navigation- Resolves HW ID to NetBox numeric ID via
GET /api/inventory, then navigates to/item/:id - Graceful camera-denied error state (no crash)
- Rear camera preference (label matching:
web/src/router.tsx— scanRoute useslazy()+Suspenseto code-split the 444KB @zxing chunknpm run buildexits 0, dist contains correctly split bundles
Task Commits
- Task 1: PWA manifest, service worker, icons, registration hook —
95a50f4 - Task 2: QR scanner page + router wiring —
75c91a5
Deviations from Plan
Auto-fixed Issues
1. [Rule 3 - Blocking] Created api.ts and AppShell.tsx stubs — parallel plan dependencies missing
- Found during: Task 2 (creating ScanPage.tsx)
- Issue: ScanPage imports
fetchInventoryfrom@/lib/apiandAppShellfrom@/components/layout/AppShell. Plans 03-03 and 03-04 (which build these) run in wave 2 alongside this plan and had not yet executed. - Fix: Created
web/src/lib/api.tswithInventoryItem,fetchInventory,fetchInventoryItemtyped wrappers (full API contract matching Plan 03-02 handler output); createdweb/src/components/layout/AppShell.tsxas a minimal page wrapper. Both files are documented as stubs that Plans 03-03/03-04 will extend. - Files modified:
web/src/lib/api.ts(new),web/src/components/layout/AppShell.tsx(new) - Impact: No scope creep — the stubs expose the exact interface ScanPage needs. Plans 03-03/03-04 will extend them without conflict.
- Commits:
75c91a5
2. [Rule 1 - Bug] Fixed recursive startScanner call pattern — removed self-reference via useCallback dep
- Found during: Task 2 implementation review
- Issue: Plan's ScanPage template called
startScanner()recursively inside its ownuseCallback, which would cause an undefined reference (function not yet assigned at first call). Also calledstopScannerbeforestopScannerwas defined. - Fix: Reordered hook definitions (stopScanner before startScanner), removed
startScannerfrom its own dependency array, and usedvoid startScanner()call pattern for the retry paths. - Files modified:
web/src/pages/ScanPage.tsx
Known Stubs
| Stub | File | Reason |
|---|---|---|
AppShell (minimal layout, no TopBar/nav) |
web/src/components/layout/AppShell.tsx |
Plan 03-03 will replace with full navigation shell |
fetchInventory/fetchInventoryItem (no caching) |
web/src/lib/api.ts |
Plan 03-03 will add TanStack Query hooks wrapping these; raw fetch is fully functional |
Both stubs are wire-complete (they make real API calls). ScanPage functionality is not blocked by stub status.
Threat Surface Coverage
All four threats from the plan's threat register are addressed:
| Threat | Mitigation | Where |
|---|---|---|
| T-03-14: QR text → navigation tampering | extractHWID() strict regex HW-\d{5,} — arbitrary text cannot trigger navigation; NetBox numeric ID comes from server response, not QR content |
ScanPage.tsx:extractHWID |
| T-03-15: Camera stream info disclosure | @zxing decodes frames locally; no frames sent to server | ScanPage.tsx (client-only) |
| T-03-16: SW cache tampering | API responses explicitly excluded (network-only path in sw.js) | sw.js fetch handler |
| T-03-17: Rapid QR scan DoS | lastScanned state debounce; scanner stops before resolving |
ScanPage.tsx:startScanner callback |
Self-Check
Files created:
- web/public/manifest.json: FOUND
- web/public/sw.js: FOUND
- web/public/icons/icon-192.png: FOUND (valid PNG)
- web/public/icons/icon-512.png: FOUND (valid PNG)
- web/src/hooks/usePWA.ts: FOUND
- web/src/pages/ScanPage.tsx: FOUND
- web/src/lib/api.ts: FOUND
- web/src/components/layout/AppShell.tsx: FOUND
Commits:
95a50f4: feat(03-05): PWA manifest, service worker, icons, and registration hook75c91a5: feat(03-05): QR scanner page with @zxing/browser and router wiring
Build: cd web && npm run build exits 0, 4 output files in dist/