Include all precached assets in the service worker revision

The build revision now hashes index.html, the sw.js source, the web app
manifest and every precached icon (sorted by path, length-prefixed), so a
deploy that changes only the manifest or an icon ships a new worker and
fresh caches.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

admin/src/pwa/pwa.test.ts

@@ -2,7 +2,11 @@ import { existsSync, readFileSync } from "node:fs";
 import { dirname, resolve } from "node:path";
 import { fileURLToPath } from "node:url";
 import { afterEach, describe, expect, it, vi } from "vitest";
-import { REVISION_MARKER, injectServiceWorker } from "../../vite-sw-plugin";
+import {
+  REVISION_MARKER,
+  STATIC_PRECACHE_FILES,
+  injectServiceWorker,
+} from "../../vite-sw-plugin";
 import { registerServiceWorker } from "./register";
 
 const adminRoot = resolve(dirname(fileURLToPath(import.meta.url)), "../..");
@@ -245,10 +249,17 @@ const referencedAssets = (html: string) =>
     .filter((url) => url.origin === "https://admin.test")
     .map((url) => url.href);
 
+// The unhashed files the build hashes into the revision, read from public/.
+const staticFiles = STATIC_PRECACHE_FILES.map((path) => ({
+  path,
+  bytes: readFileSync(publicPath(`/${path}`)),
+}));
+const revisionOf = (src: string) => /const REVISION = "([0-9a-f]+)";/.exec(src)?.[1];
+
 describe("build-time service worker injection", () => {
   it("precaches every asset the cached index.html references on install (PWA-001)", async () => {
     const html = builtIndexHtml("Ab12Cd34");
-    const built = injectServiceWorker(html, swSource);
+    const built = injectServiceWorker(html, swSource, staticFiles);
     const sw = loadServiceWorker(async (url) =>
       new FakeResponse(url.endsWith("/index.html") ? html : `net:${url}`),
     built);
@@ -272,20 +283,41 @@ describe("build-time service worker injection", () => {
   });
 
   it("derives a new revision for different index.html content (PWA-002)", () => {
-    const a = injectServiceWorker(builtIndexHtml("aaaa1111"), swSource);
+    const a = injectServiceWorker(builtIndexHtml("aaaa1111"), swSource, staticFiles);
-    const b = injectServiceWorker(builtIndexHtml("bbbb2222"), swSource);
+    const b = injectServiceWorker(builtIndexHtml("bbbb2222"), swSource, staticFiles);
-    const revisionOf = (src: string) => /const REVISION = "([0-9a-f]+)";/.exec(src)?.[1];
 
     expect(a).not.toContain(REVISION_MARKER);
     expect(b).not.toContain(REVISION_MARKER);
     expect(revisionOf(a)).toMatch(/^[0-9a-f]{12}$/);
     expect(revisionOf(b)).toMatch(/^[0-9a-f]{12}$/);
     expect(revisionOf(a)).not.toBe(revisionOf(b));
-    expect(injectServiceWorker(builtIndexHtml("aaaa1111"), swSource)).toBe(a);
+    expect(injectServiceWorker(builtIndexHtml("aaaa1111"), swSource, staticFiles)).toBe(a);
+  });
+
+  it("derives a new revision when only a precached static file changes (PWA-002)", () => {
+    const html = builtIndexHtml("aaaa1111");
+    const base = revisionOf(injectServiceWorker(html, swSource, staticFiles));
+    const withChanged = (path: string) =>
+      staticFiles.map((f) =>
+        f.path === path ? { path, bytes: Buffer.concat([f.bytes, Buffer.from([0])]) } : f,
+      );
+
+    expect(revisionOf(injectServiceWorker(html, swSource, [...staticFiles].reverse()))).toBe(base);
+    for (const path of STATIC_PRECACHE_FILES) {
+      const changed = revisionOf(injectServiceWorker(html, swSource, withChanged(path)));
+      expect(changed, path).toMatch(/^[0-9a-f]{12}$/);
+      expect(changed, path).not.toBe(base);
+    }
+  });
+
+  it("hashes every unhashed URL sw.js precaches (PWA-002)", () => {
+    const shellUrls = [...swSource.matchAll(/^\s*"(\/[^"]*)",$/gm)].map((m) => m[1]);
+    const fixed = shellUrls.filter((url) => url !== "/" && url !== "/index.html");
+    expect(fixed.map((url) => url.slice(1)).sort()).toEqual([...STATIC_PRECACHE_FILES].sort());
   });
 
   it("names both caches after the build revision (PWA-002)", async () => {
-    const built = injectServiceWorker(builtIndexHtml("aaaa1111"), swSource);
+    const built = injectServiceWorker(builtIndexHtml("aaaa1111"), swSource, staticFiles);
     const revision = /const REVISION = "([0-9a-f]+)";/.exec(built)![1];
     const sw = loadServiceWorker(async (url) => new FakeResponse(`net:${url}`), built);
 
@@ -298,11 +330,11 @@ describe("build-time service worker injection", () => {
   });
 
   it("fails fast when sw.js lacks the placeholders", () => {
-    expect(() => injectServiceWorker(builtIndexHtml("x"), "const SHELL_URLS = [];")).toThrow();
+    expect(() => injectServiceWorker(builtIndexHtml("x"), "const SHELL_URLS = [];", staticFiles)).toThrow();
   });
 
   it("activation deletes only stale nestquest-admin caches (PWA-003)", async () => {
-    const built = injectServiceWorker(builtIndexHtml("aaaa1111"), swSource);
+    const built = injectServiceWorker(builtIndexHtml("aaaa1111"), swSource, staticFiles);
     const sw = loadServiceWorker(async (url) => new FakeResponse(`net:${url}`), built);
     for (const name of [
       "nestquest-admin-shell-old",

admin/vite-sw-plugin.ts

@@ -10,6 +10,18 @@ import type { Plugin } from "vite";
 
 export const REVISION_MARKER = "__NQ_BUILD_REVISION__";
 const PRECACHE_PLACEHOLDER = "const PRECACHE_ASSETS = [];";
+// Unhashed files sw.js precaches by fixed URL, relative to the build output.
+export const STATIC_PRECACHE_FILES = [
+  "manifest.webmanifest",
+  "icons/icon-192.png",
+  "icons/icon-512.png",
+  "icons/icon-maskable-512.png",
+];
+
+export interface PrecacheFile {
+  path: string;
+  bytes: string | Uint8Array;
+}
 
 // Every same-origin URL an index.html loads via <script src> or <link href>,
 // normalised to an absolute path, in document order and without duplicates.
@@ -24,17 +36,34 @@ export function extractShellAssets(indexHtml: string): string[] {
   return [...new Set(urls)];
 }
 
+// Hash of every precached file, sorted by path; each entry is length-prefixed
+// so no two different file sets hash the same concatenation.
+export function computeRevision(files: PrecacheFile[]): string {
+  const hash = createHash("sha256");
+  for (const { path, bytes } of [...files].sort((a, b) => (a.path < b.path ? -1 : a.path > b.path ? 1 : 0))) {
+    const data = typeof bytes === "string" ? Buffer.from(bytes, "utf8") : bytes;
+    hash.update(`${path}\0${data.byteLength}\0`).update(data);
+  }
+  return hash.digest("hex").slice(0, 12);
+}
+
 // Returns swSource with the precache list and the build revision filled in.
-export function injectServiceWorker(indexHtml: string, swSource: string): string {
+// The revision covers index.html (and so the hashed bundles it names), the
+// sw.js source and the bytes of every unhashed static file it precaches.
+export function injectServiceWorker(
+  indexHtml: string,
+  swSource: string,
+  staticFiles: PrecacheFile[],
+): string {
   if (!swSource.includes(PRECACHE_PLACEHOLDER) || !swSource.includes(REVISION_MARKER)) {
     throw new Error("sw.js is missing the PRECACHE_ASSETS placeholder or revision marker");
   }
   const assets = extractShellAssets(indexHtml);
-  const revision = createHash("sha256")
+  const revision = computeRevision([
-    .update(indexHtml)
+    { path: "index.html", bytes: indexHtml },
-    .update(swSource)
+    { path: "sw.js", bytes: swSource },
-    .digest("hex")
+    ...staticFiles,
-    .slice(0, 12);
+  ]);
   return swSource
     .replace(PRECACHE_PLACEHOLDER, `const PRECACHE_ASSETS = ${JSON.stringify(assets)};`)
     .replaceAll(REVISION_MARKER, revision);
@@ -51,7 +80,14 @@ export function serviceWorkerInjectPlugin(): Plugin {
     writeBundle() {
       const swPath = resolve(outDir, "sw.js");
       const indexHtml = readFileSync(resolve(outDir, "index.html"), "utf8");
-      writeFileSync(swPath, injectServiceWorker(indexHtml, readFileSync(swPath, "utf8")));
+      const staticFiles = STATIC_PRECACHE_FILES.map((path) => ({
+        path,
+        bytes: readFileSync(resolve(outDir, path)),
+      }));
+      writeFileSync(
+        swPath,
+        injectServiceWorker(indexHtml, readFileSync(swPath, "utf8"), staticFiles),
+      );
     },
   };
 }