npm install queuing``
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A Forked module from queue with ES6 Syntax, and a retry feature
Asynchronous function queue with adjustable concurrency.
This module exports a class Queuing that implements most of the Array API. Pass async functions (ones that accept a callback or return a promise) to an instance's additive array methods. Processing begins when you call q.start().
Test
API
$3
Constructor. may contain inital values for:
* q.concurrency
*
*
*
*
* Instance methods
$3
cb, if passed, will be called when the queue empties or when an error occurs.$3
Stops the queue. can be resumed with .$3
Stop and empty the queue immediately.Instance methods mixed in from
Array
Mozilla has docs on how these methods work here.
$3
$3
Properties
$3
Max number of jobs the queue should process concurrently, defaults to .$3
Milliseconds to wait for a job to execute its callback.$3
Ensures the queue is always running if jobs are available. Useful in situations where you are using a queue only for concurrency control.$3
An array to set job callback arguments on.$3
Put back the job in que upon error.$3
Milliseconds to wait before job execution per session$3
Jobs pending + jobs to process (readonly).Events
$3
After a job executes its callback.$3
After a job passes an error to its callback.$3
After a job passes an error and queued back to jobs list$3
After q.timeout milliseconds have elapsed and a job has not executed its callback.$3
After all jobs have been processedExample
` javascript
var queue = require('queuing')var q = queue()
var results = []
// add jobs using the familiar Array API
q.push(function (cb) {
results.push('two')
cb()
})
q.push(
function (cb) {
results.push('four')
cb()
},
function (cb) {
results.push('five')
cb()
}
)
// jobs can accept a callback or return a promise
q.push(function () {
return new Promise(function (resolve, reject) {
results.push('one')
resolve()
})
})
q.unshift(function (cb) {
results.push('one')
cb()
})
// use the timeout feature to deal with jobs that
// take too long or forget to execute a callback
q.timeout = 100
q.on('timeout', function (next, job) {
console.log('job timed out:', job.toString().replace(/\n/g, ''))
next()
})
q.push(function (cb) {
setTimeout(function () {
console.log('slow job finished')
cb()
}, 200)
})
q.push(function (cb) {
console.log('forgot to execute callback')
})
// get notified when jobs complete
q.on('success', function (result, job) {
console.log('job finished processing:', job.toString().replace(/\n/g, ''))
})
// begin processing, get notified on end / failure
q.start(function (err) {
if (err) throw err
console.log('all done:', results)
})
`
Releases
The latest stable release is published to npm.
* 1.0.0
* Initial fork
* New option
* 1.1.0
* Removal of non-useful Array methods
* Refactor test
* Rename reque option to retry option
* Add delay option
* Emitter will only emit end event if the job que is empty on process.nextTick's event, approx 4-5 millisecond
* Wrap all jobs inside a promise* 1.3.0
* Update modules
* Extend nodejs compatibilty to Nodejs 12
* Use Travis
Releases from original module
The latest stable release is published to npm. Abbreviated changelog below:
* 4.4
* Add results feature
* 4.3
* Add promise support (@kwolfy)
* 4.2
* Unref timers on end
* 4.1
* Add autostart feature
* 4.0
* Change license to MIT
* 3.1.x
* Add .npmignore
* 3.0.x
* Change the default concurrency to Infinity
* Allow to accept an optional callback executed on q.emit('end')`This work is free. You can redistribute it and/or modify it under the
terms of the MIT License.
See LICENSE for full details.