horse-betting/btc-ui-app-2/node_modules/piscina/test/pool.ts
2025-06-19 16:39:08 +05:30

55 lines
1.4 KiB
TypeScript

import { resolve } from 'node:path';
import { test } from 'tap';
import Piscina from '../dist';
test('workerCreate/workerDestroy should be emitted while managing worker lifecycle', async t => {
let index = 0;
// Its expected to have one task get balanced twice due to the load balancer distribution
// first task enters, its distributed; second is enqueued, once first is done, second is distributed and normalizes
t.plan(2);
let newWorkers = 0;
let destroyedWorkers = 0;
const pool = new Piscina({
filename: resolve(__dirname, 'fixtures/eval.js'),
maxThreads: 3,
minThreads: 3,
concurrentTasksPerWorker: 1,
loadBalancer (_task, workers) {
// Verify distribution to properly test this feature
const candidate = workers[index++ % workers.length];
if (candidate != null && candidate.currentUsage >= 1) {
return null;
}
return candidate;
}
});
pool.on('workerCreate', () => {
newWorkers++;
});
pool.on('workerDestroy', () => {
destroyedWorkers++;
});
const tasks = [];
const controller = new AbortController();
const signal = controller.signal;
tasks.push(pool.run('while (true) {}', {
signal
}));
for (let n = 0; n < 10; n++) {
tasks.push(pool.run('new Promise(resolve => setTimeout(resolve, 500))'));
}
controller.abort();
await Promise.allSettled(tasks);
await pool.close();
t.equal(destroyedWorkers, 4);
t.equal(newWorkers, 4);
});