screentinker/server/test/storm-harness.test.js
ScreenTinker 4547a677ab test(#146) P3.9: de-flake storm harness — keep max-gap invariant, drop tick-count
The storm harness asserted a tick COUNT (environment-timing-sensitive) that could flake
in CI. Kept the real invariant (max event-loop gap < 300ms) and loosened the tick
assertion to >=2 (enough to have measured a real gap), which cannot flake.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-30 22:14:17 -05:00

80 lines
4.1 KiB
JavaScript

'use strict';
// #146 hardening — THE BULLETPROOF PROOF. Combine, all at once:
// - a pre-bloated device_status_log (300k rows — the incident amplifier),
// - a maintenance sweep running over it (the old whole-table sort froze 40-48s),
// - a device flapping hard (the trigger),
// - an OTA download flood from a single SNAT IP,
// and assert the event loop NEVER enters a multi-second freeze and the server stays
// responsive throughout (no NaN-sample block), while every limiter still bites.
const os = require('node:os');
const path = require('node:path');
const crypto = require('node:crypto');
process.env.DATA_DIR = path.join(os.tmpdir(), 'st-storm-' + crypto.randomBytes(4).toString('hex'));
process.env.STATUS_LOG_MAX_ROWS_PER_DEVICE = '500';
process.env.STATUS_LOG_PRUNE_BATCH = '2000';
process.env.STATUS_LOG_RETENTION_DAYS = '3';
process.env.CONNECT_RATE_MAX = '20';
process.env.OTA_DOWNLOAD_MAX_PER_WINDOW = '120';
const { test } = require('node:test');
const assert = require('node:assert/strict');
const { db, pruneStatusLog } = require('../db/database');
const flap = require('../lib/flap-limiter');
const otaGuard = require('../lib/ota-download-guard');
const chunked = require('../lib/chunked-prune');
test('storm: bloated-table sweep + flapper + OTA flood — loop stays responsive, limiters bite', async () => {
chunked.__setBandForTest(() => 'normal');
flap.reset();
// Pre-bloat: 300k rows across a few flapping devices (recent -> the cap prune must
// remove ~299k+ of them).
db.exec('DELETE FROM device_status_log');
const ins = db.prepare('INSERT INTO device_status_log (device_id, status, timestamp) VALUES (?, ?, ?)');
const now = Math.floor(Date.now() / 1000);
db.transaction(() => {
for (let i = 0; i < 300000; i++) ins.run('dev-' + (i % 3), i % 2 ? 'online' : 'offline', now);
})();
assert.equal(db.prepare('SELECT COUNT(*) c FROM device_status_log').get().c, 300000, 'seeded 300k');
// Event-loop responsiveness probe: max gap between 10ms ticks = worst sync block.
let maxGap = 0, last = Date.now(), ticks = 0;
const ticker = setInterval(() => { const n = Date.now(); maxGap = Math.max(maxGap, n - last); last = n; ticks++; }, 10);
// The amplifier sweep (chunked) runs concurrently with the storms below.
const prunePromise = pruneStatusLog({ bandGate: false });
// Flapper storm + OTA flood from ONE SNAT IP, driven in yielding rounds.
let flapRefused = 0, otaShed = 0, otaServed = 0;
const guardState = otaGuard.newState();
const stormPromise = (async () => {
for (let round = 0; round < 300; round++) {
for (let i = 0; i < 40; i++) {
if (!flap.check('d:storm-flapper').allow) flapRefused++; // one hard flapper (identity-keyed, never IP)
const a = otaGuard.admit(guardState, 'elevated'); // under load -> band-aware caps engage
if (a.allow) { otaServed++; otaGuard.release(guardState); } else otaShed++;
}
await new Promise((r) => setImmediate(r));
}
})();
const [deleted] = await Promise.all([prunePromise, stormPromise]);
clearInterval(ticker);
// 1) THE REAL INVARIANT — NO multi-second freeze. The old whole-table sort would
// freeze the ticker for tens of seconds here.
assert.ok(maxGap < 300, `loop never froze — max event-loop gap ${maxGap}ms (was 40-48s pre-fix)`);
// #146 P3.9: the exact tick count is environment-timing-sensitive; assert only that
// the ticker sampled enough to have MEASURED a real gap (>=2), not a brittle count.
assert.ok(ticks >= 2, `ticker sampled the run (${ticks} ticks) — max-gap measurement is meaningful`);
// 2) The sweep actually drained the backlog to the cap.
assert.ok(deleted >= 298000, `sweep trimmed the backlog (${deleted} deleted)`);
assert.equal(db.prepare('SELECT COUNT(*) c FROM device_status_log').get().c, 1500, '3 devices x 500 cap');
// 3) Every limiter still bit under load.
assert.ok(flapRefused > 0, 'the flapper was refused (flap limiter bit)');
assert.ok(otaShed > 0, 'the OTA flood was shed past the global window cap');
assert.ok(otaServed <= 120, `OTA served capped at the window max (${otaServed})`);
});