# multi-process-worker

> ![](https://img.shields.io/npm/v/multi-process-worker) ![](https://img.shields.io/npm/dt/multi-process-worker)

Latest version **2.0.7** (published 2022-08-16) · 0 weekly downloads

## Install

```sh
npm install multi-process-worker
pnpm add multi-process-worker
yarn add multi-process-worker
bun add multi-process-worker
```

## Health

**Score 15/100 (F)** — status: abandoned.

Positive: no vulnerabilities.

Warnings: low downloads; no types; no esm support.

Negative: abandoned; low maintenance score.

## Facts

| | |
|---|---|
| Version | 2.0.7 |
| Published | 2022-08-16 |
| First published | 2019-09-03 |
| Weekly downloads | 0 |
| TypeScript types | none |
| Module format | CommonJS |
| Dependencies | 2 |
| Unpacked size | 26 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| GitHub stars | 1 |
| Maintainers | cenfun |

## Links

- npm: https://www.npmjs.com/package/multi-process-worker
- Repository: https://github.com/cenfun/multi-process-worker
- Homepage: https://github.com/cenfun/multi-process-worker#readme
- Issues: https://github.com/cenfun/multi-process-worker/issues
- npm.io page: https://npm.io/package/multi-process-worker

## Dependencies (2)

- [console-grid](https://npm.io/package/console-grid.md) ^2.0.0
- [eight-colors](https://npm.io/package/eight-colors.md) ^1.0.1

## Recent versions

- 2.0.7 (latest) — 2022-08-16
- 2.0.6 — 2020-11-17
- 2.0.5 — 2020-09-13
- 2.0.4 — 2020-08-06
- 2.0.3 — 2020-08-03
- 2.0.2 — 2019-10-29
- 2.0.1 — 2019-10-28
- 2.0.0 — 2019-10-26
- 1.0.5 — 2019-09-29
- 1.0.4 — 2019-09-28
- 1.0.3 — 2019-09-28
- 1.0.2 — 2019-09-04
- 1.0.1 — 2019-09-03

## README

# Multi Process Worker
![](https://img.shields.io/npm/v/multi-process-worker)
![](https://img.shields.io/npm/dt/multi-process-worker)

* Create multiple child processes as workers for jobs
* Use master process as worker if only one job to do (low performance if create child process)

## Install 
```sh
npm i multi-process-worker
```
## Usage
```js
//master.js for master process
const MPW = require("multi-process-worker");
const option = {
    name: "MPW",
    workerEntry: 'worker.js',
    workerHandler: null,
    workerLength: 2,
    jobList: [{
        name: "job1",
        jobTimeout: 5000
    }, {
        name: "job2"
    }, {
        name: "error-job"
    }, {
        name: "job3"
    }],
    jobTimeout: 10 * 1000,
    failFast: false,
    workerOption: {
        property: "value"
    },
    onStart: async () => {
        console.log('onStart');
    },
    onMessage: (message) => {
        console.log(`================ onMessage: ${message}`);
    },
    onJobStart: (job) => {
        console.log(`${job.jobName}: ${job.jobId} - start ${job.name}`);
    },
    onJobFinish: (job, o) => {
        console.log(`${job.jobName}: ${job.jobId} - finish ${job.name}`, `cost ${job.duration.toLocaleString()}ms`);
        console.log(o.stats);
    },
    onFinish: async (o) => {
        console.log('onFinish');
        if (o.code !== 0) {
            console.log(o.name + ': jobs stopped with error: ' + o.code);
        }
    }
};
const code = await MPW(option);
```
see [/test/master.js](/test/master.js)

```js
//worker.js for child process
process.on('message', async (message) => {
    if (message.type === "workerStart") {
        let workerOption = message.data;
        console.log(workerOption);
        process.send({
            type: "workerOnline"
        });
        return;
    }
    if (message.type === "jobStart") {
        var job = message.data;
        job.code = await workerHandler(job, process);
        process.send({
            type: "jobFinish",
            data: job
        });
        return;
    }
});
```
see [/test/worker.js](/test/worker.js) and [/test/handler.js](/test/handler.js)

## Test
```
npm run test
```

![](/test/multi-process-worker.png)

## Master Events 
* workerStart
* jobStart

## Worker Events
* workerOnline
* workerMessage
* jobFinish

## Debug child process with VSCode
```js
{
    "version": "0.2.0",
    "configurations": [{
        "type": "node",
        "request": "launch",
        "name": "Launch Program",
        "autoAttachChildProcesses": true,
        "cwd": "${workspaceFolder}/test",
        "program": "${workspaceFolder}/test/master.js"
    }]
}
```

## CHANGELOG

+ v2.0.7
  - updated deps

+ v2.0.6
  - fixed duration

+ v2.0.5
  - added workerMessage event

+ v2.0.4
  - added stats(percent,elapsedTime,estimatedTime) when job finished

+ v2.0.3
  - fixed output log

+ v2.0.2
  - fixed worker duration if nothing done

+ v2.0.1
  - (API breaking change) do not create child process if only one worker required, replace with workerHandler

+ v1.0.5
  - logCost support worker level only

+ v1.0.4
  - fix jobTimeout

+ v1.0.3
  - add jobTimeout

+ v1.0.2
  - fix min mem

---
_Source: https://npm.io/package/multi-process-worker · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._