https://github.com/pyldin601/long-long-job

Library for execution of long chain of tasks with ability to resume it's state on restart.
https://github.com/pyldin601/long-long-job

Last synced: about 1 month ago
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Library for execution of long chain of tasks with ability to resume it's state on restart.

• Host: GitHub
• URL: https://github.com/pyldin601/long-long-job
• Owner: pyldin601
• License: mit
• Created: 2018-01-31T11:06:29.000Z (almost 7 years ago)
• Default Branch: master
• Last Pushed: 2023-12-15T11:57:18.000Z (about 1 year ago)
• Last Synced: 2024-12-08T22:00:12.415Z (about 2 months ago)
• Language: JavaScript
• Homepage:
• Size: 87.9 KB
• Stars: 0
• Watchers: 0
• Forks: 0
• Open Issues: 2
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
# long-long-job

[![Build Status](https://travis-ci.org/pldin601/long-long-job.svg?branch=master)](https://travis-ci.org/pldin601/long-long-job)

[![Coverage Status](https://coveralls.io/repos/github/pldin601/long-long-job/badge.svg?branch=master)](https://coveralls.io/github/pldin601/long-long-job?branch=master)

```basic

10 PRINT "HELLO"

20 GOTO 10

```

## What?

This module ables you to create a chain of tasks (computations or actions) with ability to resume run state on restart.

Each task receives state of previous task (or initial state if it is first in chain) and must return action what to do next composed with new state.

## Example

First of all we need to define where job's state will be stored during transitions. Then we must initialize module with it.

For example, we will store state in `Map` object. This is simplest storage method and it won't preserve state during restarts.

### LongLongJob.js

```javascript

const { longLongJob } = require('long-long-job');

const mapBasedStorage = () => {

  const stateStore = new Map();

  return {

    async hasState(id) {

      return stateStore.has(id);

    },

    async setState(id, state) {

      stateStore.set(id, state);

    },

    async getState(id) {

      return stateStore.get(id);

    },

    async clean(id) {

      stateStore.delete(id);

    },

  };

};

module.exports = longLongJob(mapBasedStorage());

```

### incrementJob.js

```javascript

const LongLongJob = require('./LongLongJob');

const { repeat, next } = require('long-long-job');

const incrementJob = new LongLongJob('increment-job', [

  async ({ value, threshold }) => {

    incrementJob.emit('tick', value);

    return value < threshold 

      ? repeat({ value: value + 1, threshold })

      : next({ value, threshold });

  },

]);

module.exports = incrementJob;

```

### main.js

```javascript

const incrementJob = require('./incrementJob');

incrementJob.on('start', () => console.log('Job started'));

incrementJob.on('resume', () => console.log('Job resumed'));

incrementJob.on('tick', value => console.log('Current value is %d', value));

incrementJob.on('done', () => console.log('Job finished'));

incrementJob

  .start({ value: 0, threshold: 1000 })

  .then(({ value }) => console.log('Task is done with value %d', value));

```