@danielkalen/listr
v0.5.0
Published
Terminal task list (modified to not stop list upon errors when concurrent:true)
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listr
Terminal task list
Install
$ npm install --save listr
Usage
const execa = require('execa');
const Listr = require('listr');
const tasks = new Listr([
{
title: 'Git',
task: () => {
return new Listr([
{
title: 'Checking git status',
task: () => execa.stdout('git', ['status', '--porcelain']).then(result => {
if (result !== '') {
throw new Error('Unclean working tree. Commit or stash changes first.');
}
})
},
{
title: 'Checking remote history',
task: () => execa.stdout('git', ['rev-list', '--count', '--left-only', '@{u}...HEAD']).then(result => {
if (result !== '0') {
throw new Error('Remote history differ. Please pull changes.');
}
})
}
], {concurrent: true});
}
},
{
title: 'Install package dependencies',
task: () => execa('npm', ['install'])
},
{
title: 'Run tests',
task: () => execa('npm', ['test'])
},
{
title: 'Publish package',
task: () => execa('npm', ['publish'])
}
]);
tasks.run().catch(err => {
console.error(err);
});
Task
A task
can return different values. If a task
returns, it means the task was completed successfully. If a task throws an error, the task failed.
const tasks = new Listr([
{
title: 'Success',
task: () => 'Foo'
},
{
title: 'Failure',
task: () => {
throw new Error('Bar')
}
}
]);
Promises
A task
can also be async by returning a Promise
. If the promise resolves, the task completed successfully, it it rejects, the task failed.
const tasks = new Listr([
{
title: 'Success',
task: () => Promise.resolve('Foo')
},
{
title: 'Failure',
task: () => Promise.reject('Bar')
}
]);
Observable
A task
can also return an Observable
. The thing about observables is that it can emit multiple values and can be used to show the output of the
task. Please note that only the last line of the output is rendered.
const tasks = new Listr([
{
title: 'Success',
task: () => {
return new Observable(observer => {
observer.next('Foo');
setTimeout(() => {
observer.next('Bar');
}, 2000);
setTimeout(() => {
observer.complete();
}, 4000);
});
}
},
{
title: 'Failure',
task: () => Promise.reject(new Error('Bar'))
}
]);
Streams
It's also possible to return a stream
. The stream will be converted to an Observable
and handled as such.
Skipping tasks
Optionally specify a skip
function to determine whether a task can be skipped.
- If the
skip
function returns a truthy value or aPromise
that resolves to a truthy value then the task will be skipped. - If the returned value is a string it will be displayed as the reason for skipping the task.
- If the
skip
function returns a falsey value or aPromise
that resolves to a falsey value then the task will be executed as normal. - If the
skip
function throws or returns aPromise
that rejects, the task (and the whole build) will fail.
const tasks = new Listr([
{
title: 'Task 1',
task: () => Promise.resolve('Foo')
},
{
title: 'Can be skipped',
skip: () => {
if (Math.random() > 0.5) {
return 'Reason for skipping';
}
},
task: () => 'Bar'
},
{
title: 'Task 3',
task: () => Promise.resolve('Bar')
}
]);
API
Listr([tasks], [options])
tasks
Type: object[]
List of tasks.
title
Type: string
Title of the task.
task
Type: Function
Task function.
skip
Type: Function
Skip function. Read more about skipping tasks.
options
showSubtasks
Type: boolean
Default: true
Set to false
if you want to disable the rendering of the subtasks. Subtasks will be rendered if
an error occurred in one of them.
concurrent
Type: boolean
Default: false
Set to true
if you want tasks to run concurrently.
Instance
add(task)
Returns the instance.
task
Type: object
object[]
Task object or multiple task objects.
run()
Start executing the tasks.
Related
- ora - Elegant terminal spinner
- cli-spinners - Spinners for use in the terminal
License
MIT © Sam Verschueren