Cache the page-owned app response before starting the worker

frontend/app-bootstrap.test.js

@@ -0,0 +1,45 @@
+const {test}=require('node:test');
+const assert=require('node:assert/strict');
+const {webcrypto,createHash}=require('node:crypto');
+const vm=require('node:vm');
+const {readFileSync}=require('node:fs');
+function fixture({cached=false,tampered=false,enabled=true,loading=false,quota=false,insecure=false}={}){
+ const source='window.appRuns=(window.appRuns||0)+1; window.boot=()=>window.bootRuns=(window.bootRuns||0)+1; document.addEventListener("DOMContentLoaded",boot);',hash=createHash('sha256').update(source).digest('hex'), key='/app.js?v='+hash.slice(0,10);
+ const held=new Map(), appended=[],listeners={};let calls=0;
+ const response=()=>new Response(tampered?'bad':source,{headers:{'X-Asset-Hash':hash.slice(0,10)}});
+ if(cached)held.set(key,response());
+ const root={crypto:insecure?undefined:webcrypto,TextDecoder,Uint8Array,btoa,console,Lazy:{manifest:{appCache:enabled,files:{'/app.js':{h:hash.slice(0,10)}}},url:()=>key},fetch:async()=>{calls++;return response();},caches:{open:async()=>({match:async k=>held.get(k)?.clone(),put:async(k,r)=>{if(quota)throw Error('quota');held.set(k,r.clone());}})}};
+ const doc=root.document={readyState:loading?'loading':'complete',querySelector:()=>({content:"script-src 'self' 'sha256-"+Buffer.from(hash,'hex').toString('base64')+"'"}),addEventListener:(name,fn)=>(listeners[name] ||= []).push(fn),createElement:()=>({remove(){this.removed=true;}}),head:{append(node){appended.push(node);if(node.textContent)vm.runInContext(node.textContent,context);else {vm.runInContext(source,context);queueMicrotask(()=>node.onload());}}}};
+ root.window=root;const context=vm.createContext(root);
+ vm.runInContext(readFileSync(require.resolve('./app-bootstrap.js'),'utf8'),context);
+ return {root,held,appended,listeners,key,calls:()=>calls,doc,response};
+}
+test('cold boot caches verified app before execution so worker skips its download',async()=>{
+ const f=fixture();await f.root.AppBootstrap.ready;assert.equal(f.calls(),1);assert.ok(f.held.has(f.key));assert.equal(f.root.appRuns,1);assert.equal(f.root.bootRuns,1);assert.equal(f.appended[0].src,undefined);assert.equal(f.appended[0].removed,true);
+});
+test('offline boot reads the exact cached app without network or re-evaluation',async()=>{
+ const f=fixture({cached:true});await f.root.AppBootstrap.ready;assert.equal(f.calls(),0);assert.equal(f.root.appRuns,1);assert.equal(f.root.bootRuns,1);
+});
+test('tampered cached bytes are rejected before execution',async()=>{
+ const f=fixture({cached:true,tampered:true});await assert.rejects(f.root.AppBootstrap.ready,/hash/);assert.equal(f.root.appRuns,undefined);
+});
+test('native and rollback boot use the original external classic script',async()=>{
+ const f=fixture({enabled:false});await f.root.AppBootstrap.ready;assert.equal(f.calls(),0);assert.equal(f.appended[0].src,f.key);assert.equal(f.root.bootRuns,1);
+});
+test('boot waits for the normal DOM event when the parser has not finished',async()=>{
+ const f=fixture({loading:true});await f.root.AppBootstrap.ready;assert.equal(f.root.bootRuns,undefined);for(const fn of f.listeners.DOMContentLoaded)fn();assert.equal(f.root.appRuns,1);assert.equal(f.root.bootRuns,1);
+});
+test('quota failure still executes the verified response without deleting saved data',async()=>{
+ const f=fixture({quota:true});await f.root.AppBootstrap.ready;assert.equal(f.calls(),1);assert.equal(f.root.appRuns,1);assert.equal(f.root.bootRuns,1);
+});
+
+
+test('the early head response is consumed without a second page fetch',async()=>{
+ const f=fixture();f.root.Lazy.appResponse=Promise.resolve(f.response());await f.root.AppBootstrap.ready;
+ assert.equal(f.calls(),0);assert.ok(f.held.has(f.key));assert.equal(f.root.appRuns,1);
+});
+
+
+test('insecure local HTTP boot retains external execution without WebCrypto',async()=>{
+ const f=fixture({insecure:true});await f.root.AppBootstrap.ready;assert.equal(f.calls(),0);assert.equal(f.appended[0].src,f.key);assert.equal(f.root.bootRuns,1);
+});