A transient failure shouldn't cost a face its thumbnail for good.

Pinguimdarelva's picture is 52KB on a CDN that answers in 700ms one minute
and times out the next — I measured both from this machine. The thumbnail
attempt hit one of the bad minutes, and `thumbFail` was written as if the
host had refused us: never retried, so that avatar went back to fetching the
original on every boot.

Only a tainted canvas is a real refusal (no CORS header, nothing to be done),
and that is remembered for good. Everything else — a load error, or a host
that won't answer inside twenty seconds — is stamped with the time and tried
again in six hours. The timeout also frees the slot: three thumbnails run at
a time, and a hanging image used to hold one of them indefinitely.

And zap tallies are remembered between sessions. They were asked of the
relays on every boot, which takes seconds, so a room full of zapped messages
painted bare and filled in afterwards. The totals (never the receipts) are
kept locally and painted straight away; the moment the relays answer for a
message, their word replaces it — so a tally that changed, or a receipt that
was deleted, still settles correctly. Opening a DM thread doesn't forget what
the chat had learned, and the store is capped at 400.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_019mrt228Upn9nNCwGixzSLx

1 files changed, 69 insertions, 0 deletions

diff --git a/tools/zap-tally-cache-test.js b/tools/zap-tally-cache-test.js
new file mode 100644
index 0000000..98cfe7e
--- /dev/null
+++ b/tools/zap-tally-cache-test.js
@@ -0,0 +1,69 @@
+// Zap tallies are asked of the relays on every boot, which takes seconds. The
+// last known totals are remembered locally so a room of zapped messages
+// paints its chips straight away — and the relays' answer replaces them, so a
+// tally that changed (or a receipt that was deleted) still settles correctly.
+//
+// Run: bun tools/zap-tally-cache-test.js
+import puppeteer from 'puppeteer-core';
+import { generateMnemonic } from '@scure/bip39';
+import { wordlist } from '@scure/bip39/wordlists/english';
+import { buildHtml } from '../build.js';
+import { cacheKeyFor } from '../src/wallet.js';
+const sleep = (ms) => new Promise((r) => setTimeout(r, ms));
+let ok = true;
+const check = (n, c, d = '') => { console.log(` ${c ? '✓' : '✗'} ${n}${d ? ' — ' + d : ''}`); if (!c) ok = false; };
+const html = await buildHtml({ minify: true, pwa: false });
+const server = Bun.serve({ port: 5236, fetch: () => new Response(html, { headers: { 'content-type': 'text/html' } }) });
+const browser = await puppeteer.launch({ executablePath: '/usr/bin/google-chrome', headless: 'new', args: ['--no-sandbox'] });
+const page = await browser.newPage();
+const click = (t) => page.evaluate((x) => { const e = [...document.querySelectorAll('button')].find((n) => n.textContent.trim().toLowerCase().includes(x)); if (e) { e.click(); return true; } return false; }, t);
+const waitText = async (x, ms = 25000) => { for (let i = 0; i < ms / 250; i++) { if ((await page.evaluate(() => document.body.innerText)).toLowerCase().includes(x)) return true; await sleep(250); } return false; };
+try {
+  await page.setViewport({ width: 390, height: 844 });
+  await page.goto('http://localhost:5236/', { waitUntil: 'domcontentloaded' });
+  await page.evaluate(() => localStorage.setItem('btc-wallet-network', 'regtest'));
+  await page.reload({ waitUntil: 'domcontentloaded' });
+  await sleep(400);
+  await click('get started'); await sleep(500);
+  await click('import existing'); await sleep(400);
+  await page.waitForSelector('textarea');
+  const mnemonic = generateMnemonic(wordlist);
+  await page.type('textarea', mnemonic);
+  await click('open wallet');
+  await waitText('receive', 20000);
+
+  // the feature state slot this wallet reads (seed-keyed, as loadFeatureState does)
+  const key = cacheKeyFor(mnemonic + '\n') + ':messages';
+
+  // the shape the chat paints from: remembered totals keyed by event id
+  const painted = await page.evaluate((k) => {
+    const s = JSON.parse(localStorage.getItem(k) || '{}');
+    s.zaps = { ['a'.repeat(64)]: { s: 2100, m: 1 }, ['b'.repeat(64)]: { s: 21 } };
+    localStorage.setItem(k, JSON.stringify(s));
+    return Object.keys(s.zaps).length;
+  }, key);
+  check('seeded two remembered tallies', painted === 2);
+
+  await page.reload({ waitUntil: 'domcontentloaded' });
+  await waitText('receive', 20000);
+  // open the chat — the screen that rewrites this state, and where a stale
+  // copy being saved back would quietly drop every remembered tally
+  await page.evaluate(() => { const b = [...document.querySelectorAll('button')].find((e) => /message/i.test(e.getAttribute('aria-label') || '')); if (b) b.click(); });
+  await sleep(2500);
+  const kept = await page.evaluate((k) => {
+    const s = JSON.parse(localStorage.getItem(k) || '{}');
+    return Object.keys(s.zaps || {}).length;
+  }, key);
+  check('they survive a refresh and a trip through chat', kept === 2, kept + ' kept');
+
+  // and they are readable as tallies, not re-fetched from scratch: the
+  // seeded totals are what a chip would paint before any relay answers
+  const readable = await page.evaluate((k) => {
+    const s = JSON.parse(localStorage.getItem(k) || '{}');
+    const v = s.zaps[Object.keys(s.zaps)[0]];
+    return v && typeof v.s === 'number' && v.s > 0;
+  }, key);
+  check('a remembered tally carries its sats', readable);
+} finally { await browser.close(); server.stop(true); }
+console.log(ok ? '\n✅ tallies survive a refresh' : '\n❌ failed');
+process.exit(ok ? 0 : 1);