Implementation a thread pool pattern for node.js
npm install @datapain/matteMatte is an implementation a thread pool pattern for node.js
As we know Node.js is asynchronous but some features stay synchronous. The matte solution can help you to avoid blocking your main thread and compute sync things in another Event loop.
* Node.js - Platform
* Typescript - typed superset of JavaScript that compiles to plain JavaScript
- Node.js 12.x+
- Typescript knowledge
npm install @datapain/matte
First of all, let's look at a basic example where we want to execute some Math operation:
``typescript
import assert from 'assert';
import { WorkerPool } from '@datapain/matte';
type PowPool = { x: number; y: number };
const pow = ({ x, y }: PowPool) => {
return Math.pow(x, y);
};
const pool = new WorkerPool();
pool
.init({ workers: { timeout: 200 } })
.catch(console.error)
.then(() => {
const taskId = pool.process
handler: pow,
data: { x: 2, y: 2 },
callback: (result) => {
assert.strictEqual(result.val, 4);
console.log('Always works');
pool.terminate();
},
});
});
`$3
The next example will describe how we able to abort some tasks:typescript
import assert from 'assert';
import { WorkerPool } from '@datapain/matte';
import type { AbortSignal } from 'abort-controller';
const reallyLongTask = async (_, signal: AbortSignal) =>
new Promise((res, rej) => {
const timeoutId = setTimeout(() => {
res('BOOM!');
}, 200);
signal.addEventListener('abort', () => {
clearTimeout(timeoutId);
rej(new Error('Task was aborted'));
});
});
const pool = new WorkerPool();
pool
.init({ workers: { timeout: 100 } })
.catch(console.error)
.then(() => {
pool
.process
handler: reallyLongTask,
callback: (result) => {
result
.map(() => {
throw new Error('BOOM');
})
.mapErr((err) => {
assert.strictEqual(err.message, 'Task was aborted');
console.log('Always works!');
});
pool.terminate();
},
})
.andThen((id) => pool.abort(id));
});
`
typescript
import assert from 'assert';
import { WorkerPool } from '@datapain/matte';const pool = new WorkerPool();
pool
.init({
workers: { timeout: 100 },
fn: {
context: () => {
// @ts-ignore
this.pow = ({ x, y }) => {
return Math.pow(x, y);
};
},
},
})
.catch(console.error)
.then(() => {
pool
.process({
handler: () => {
// @ts-ignore
return pow({ x: 2, y: 2 });
},
callback: (result) => {
result.map((res) => assert.strictEqual(res, 4));
pool.terminate();
},
})
.andThen((id) => pool.abort(id));
});
``We use SemVer for versioning.