sw 0.1.4

A command-line tool to generate service worker files for web applications. It simplifies the process of creating service workers.

0.1.4 — 2026-04-22

Fixed

• Bootstrap: WebAssembly.instantiate(): Import #N "X": module is not an object or function failures on first load after a deploy. When an old SW kept controlling the page while a new SW installed in the background, any file missing from the old SW's manifest fell through to the network (fresh) while cached files stayed stale — so Flutter would load a fresh main.dart.mjs against a stale main.dart.wasm and the import schemas would disagree. Bootstrap now force-activates a pre-existing waiting worker at registration time via {type:'skipWaiting'} + controllerchange, so subsequent fetch(main.dart.wasm) / import(main.dart.mjs) go through the new SW with a coherent cache. Bounded by SW_REGISTRATION_TIMEOUT_MS; falls back to the old waitForActivation path on timeout. (packages/sw/src/bootstrap/sw-registration.ts)
• Bootstrap: pages controlled by a foreign SW at a different script path (e.g., an old flutter_service_worker.js left from a pre-migration deploy) can serve a similarly incoherent mix of files. Bootstrap now detects this pre-registration and performs a one-shot location.reload() after unregistering the offending registration. A sessionStorage guard prevents reload loops if the handoff doesn't take. (packages/sw/src/bootstrap/sw-registration.ts, packages/sw/src/bootstrap/pipeline.ts)

Changed

• Bootstrap: foreign-controller cleanup is surgical — only the registration whose active worker equals the current navigator.serviceWorker.controller is unregistered. Unrelated registrations at other scopes (typically firebase-messaging-sw.js for push notifications) are left intact so their subscriptions survive the recovery. (packages/sw/src/bootstrap/sw-registration.ts)

Scope note

• The pre-existing-waiting auto-activation is intentionally bootstrap-only: once the app is running, updates continue through the existing sw-update-available → applyUpdate user-approval flow, so running sessions are never yanked out from under the user.

0.1.3 — 2026-04-20

Fixed

• Bootstrap: Bootstrap.onUpdateAvailable handlers were silently dropped on flutter-first-frame because BootstrapAPI.dispose() cleared the updateHandlers Set alongside the (correctly load-phase-scoped) progress subscribers. Update handlers are now retained for the lifetime of the page, so apps reliably receive the "new SW installed" signal after the loading widget disappears. (packages/sw/src/bootstrap/api.ts)
• Bootstrap: the sw-update-available DOM bridge listener installed by runPipeline was registered with { once: true }, so a long-lived tab encountering a second deploy never notified handlers. The listener is now permanent for the page lifetime; wireUpdateDetection already dispatches at most once per SW install. (packages/sw/src/bootstrap/pipeline.ts)

Changed

• Bootstrap: BootstrapAPI.notifyUpdateAvailable now routes async-handler rejections to console.error instead of leaving an "Uncaught (in promise)" warning that masks the real error. (packages/sw/src/bootstrap/api.ts)

0.1.2 — 2026-04-20

Fixed

• Bootstrap: production deploys on hosts with SPA rewrites (Firebase Hosting, Netlify with index.html fallback, etc.) crashed at _flutter.loader not available after loading flutter.js because the server returned index.html for the bare flutter.js fetch. The bootstrap now inlines Flutter's flutter.js IIFE into bootstrap.js at generation time, so no runtime fetch of flutter.js is performed and the loader is available before the pipeline starts.

Changed

• Cleanup: version.json is no longer deleted — it carries Flutter's app version metadata and may be read by the app or external tooling at runtime.
• Cleanup: flutter.js is now removed from the deployed output (its loader is inlined into bootstrap.js).
• Docs: README "CI step" snippet no longer recommends rm -f build/web/flutter.js manually — the generator handles it.

0.1.1 — 2026-04-20

Added

• Docs: "Local Development" section in README.md covering the monorepo layout, TypeScript ↔ Dart build pipeline, and commands for running the generator against example/build/web/.

0.1.0 — 2026-04-20

Complete rewrite replacing Flutter's default bootstrap with a professional two-artifact system.

Fixed (post-audit hardening)

• Generator: crash on short or empty engineRevision now surfaces a clear error before artifact generation.
• CLI precedence: --flag with an ArgParser default no longer shadows YAML / env values (wasParsed gate). Glob options (--core, --required, …) now honour SW_CORE, SW_REQUIRED, SW_OPTIONAL, SW_IGNORE, SW_GLOB, SW_EXCLUDE_GLOB environment variables that previously did nothing.
• CLI: invalid --min-progress / --max-progress values now fail with exit code 64 instead of silently defaulting to 0/90.
• Cleanup: canvaskit pruning uses consistent URL-style paths, fixing a Windows case where \-separated paths never matched the keep-set.
• SW notifyClients: a single dead client no longer aborts iteration — every other client still receives the progress update.
• SW cacheFirst: non-OK responses (4xx/5xx) now emit an error progress event so the bootstrap UI can surface the failure instead of hanging on loading. Fallback 503s carry Content-Type: text/plain.
• SW swapCaches: reordered to copy-then-evict-then-persist-manifest, and eviction now excludes paths that were just re-precached from temp (no more accidental deletion of the fresh bytes).
• SW message-handler: accepts both "skipWaiting" strings and {type: "skipWaiting"|"getVersion", requestId?} objects; getVersion replies echo requestId for correlation.
• Loading widget: dispose adds a 600ms safety teardown, so the widget and its stylesheet don't leak when transitionend doesn't fire (reduced-motion, background tabs).
• CanvasKit loader: detectWebGLVersion releases its temporary canvas + GL context via WEBGL_lose_context instead of relying on GC.

Added

• Deterministic version: when --version / SW_VERSION / YAML is absent, the generator derives a stable 12-char sha256 over the manifest contents. Re-running against an unchanged build now yields the same SW version.
• Dart UI defaults → bootstrap: --logo, --title, --theme, --color, --min-progress, --max-progress flags are baked into bootstrap.js as BuildConfig.uiDefaults. data-config still overrides at runtime.
• Precache concurrency cap (PRECACHE_CONCURRENCY = 6) so large manifests don't stampede the origin during install.
• Manifest size warning: generator emits a stderr warning when sw.js exceeds 10 MB.
• Update prompt API: window.Bootstrap.onUpdateAvailable(handler) and window.Bootstrap.applyUpdate(reload=true) let apps prompt for and apply a waiting SW upgrade. sw-registration.ts exports activateWaitingSW(registration) for lower-level use.
• CI: new e2e GitHub Actions job runs flutter build web + dart run sw:generate + Playwright on each PR; SW_E2E_BROWSERS=all opts into the Chromium/Firefox/WebKit matrix.
• Tests: test/config_test.dart, test/files_test.dart, and new injector cases covering uiDefaults. Removed the empty test/unit_test.dart placeholder.

Original 0.1.0 feature set

Breaking Changes

• CLI arguments updated: new options added, some defaults changed
• Generated output now produces two files (sw.js + bootstrap.js) instead of one
• Requires <script defer data-sw-bootstrap src="bootstrap.js"> in index.html
• Old inline JS/CSS loading UI replaced by the built-in loading widget

Added

• Bootstrap pipeline — 6-stage initialization replacing flutter_bootstrap.js
  • Stages: Init → SW Registration → CanvasKit → Assets → Dart Entry → Dart Init
• Loading widget — Responsive circular progress with SVG ring, stall detection, error display, dark/light/auto theme
• CanvasKit CDN loading — Automatic engineRevision extraction, Google CDN with local fallback
• Resource categorization — Core, Required, Optional, Ignore with glob-based overrides
• Global API — window.Bootstrap.dispose(), .progress, .subscribe(cb) for Dart integration
• YAML config — sw.yaml as alternative to CLI args (priority: CLI > YAML > env > defaults)
• Exponential backoff — 3 retry attempts with 1s/2s/4s delays and jitter
• Cache busting — Hash-based ?v={hash} query params on all cached resources
• Atomic cache updates — Temp cache during install, swapped on activate
• Console logging — Styled version banner with engine revision, SW version, renderer info
• Stall detection — "Reset Cache" button after 30s without progress
• Auto-cleanup — Removes flutter_bootstrap.js, flutter_service_worker.js, version.json, .js.map, .js.symbols
• TypeScript source — SW and Bootstrap written in TypeScript, compiled via Vite to minified IIFE

Changed

• Monorepo structure: packages/sw/ (TypeScript) + root (Dart CLI)
• Service Worker rewritten in TypeScript with modular architecture
• Cache naming: {prefix}-{version} for content, {prefix}-manifest for manifest storage
• bootstrap.js, index.html, sw.js are never cached by the SW

Removed

• Inline JS/CSS string templates in Dart (replaced by compiled TypeScript)
• downloadOffline command (simplified caching model)
• Navigation preload (replaced by simpler network-first for index.html)
• Comment stripping (Vite handles minification)

0.0.7

• Simplify service worker by removing retry logic and navigation preload.
• Replace Promise.race timeout wrappers with modern AbortController-based fetchWithTimeout.
• Remove unused constants (MEDIA_EXT, NETWORK_ONLY, RETRY_DELAY).
• Remove INSTALL_TIMEOUT, ACTIVATE_TIMEOUT wrappers from install/activate events.
• Streamline activate event handler by removing redundant Promise.race nesting.

0.0.6

• Add timeout protection for install (30s) and activate (30s) events.
• Add fetch timeout (10s) and retry logic (2 retries with 500ms delay).
• Add navigation preload support for online-first strategy.
• Clean up all stale caches with matching prefix on activation.
• Ensure self.clients.claim() is always called, even on error/timeout.
• Emit sw-version.txt alongside sw.js for CI version injection.

0.0.5

• Update index.html example to include more features.

0.0.4

• Improved service worker generation.

0.0.3

• Service worker generation now based on the flutter's flutter_service_worker.js.

0.0.2

• Proof of concept for service worker generation

0.0.1

• Initial release with basic functionality