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Photo / video gallery generator
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> Drop-in [`Listr`](https://github.com/SamVerschueren/listr) subclass for tasks that need to be picked from a queue concurrently
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:information_source: *About this package*
*The main difference with the standard `concurrent: <count>` option is that tasks are only rendered as they get picked up, and disappear once processed.*
*This component will not be necessary anymore if the following `Listr` feature request is implemented: [
When it is, we can simply rely on the `concurrent: <count>` option and let Listr look after the scheduling / execution of the tasks.*
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```js
const Listr = require('listr')
const ListrWorkQueue = require('./listr-work-queue/index.js')
const tasks = new Listr([{
title: 'Running jobs',
task: () => new ListrWorkQueue(/* tasks */, {
concurrent: WORKER_COUNT,
exitOnError: false
})
}])
tasks.run().then(() => console.log('Done'))
```
Every job is an object with 2 properties, similar to the standard `Listr` tasks.
The `task` property **must** be a Promise. Observables and streams are not supported.
```js
{
title: 'Job A',
task: () => new Promise(resolve => setTimeout(resolve, 1000))
}
```
- `concurrent`: the number of workers getting tasks from the queue.
```js
{
concurrent: os.cpus().length
}
```
- `exitOnError`: whether to stop processing new jobs when one of the jobs fails (default is `true`). Note that pending tasks will still complete before the process is stopped.
```js
{
exitOnError: false
}
```
- `update()`: a callback to report on the overall progress. This can be used for example to update the parent task title.
```js
{
title: 'Running jobs',
task: (ctx, parent) => new ListrWorkQueue(/* tasks */, {
update: (completed, total) => {
parent.title = `Running jobs (${completed}/${total})`
}
})
}
```