fastq
Fast, in memory work queue. fastq is API compatible with
async.queue
Benchmarks (1 million tasks):
- setImmediate: 812ms
- fastq: 854ms
- async.queue: 1298ms
- neoAsync.queue: 1249ms
Obtained on node 12.16.1, on a dedicated server.
If you need zero-overhead series function call, check out
fastseries. For zero-overhead parallel
function call, check out fastparallel.
- Installation
- Usage
- API
- Licence & copyright
Install
npm i fastq --save
Usage
'use strict'
var queue = require('fastq')(worker, 1)
queue.push(42, function (err, result) {
if (err) { throw err }
console.log('the result is', result)
})
function worker (arg, cb) {
cb(null, 42 * 2)
}
Setting this
'use strict'
var that = { hello: 'world' }
var queue = require('fastq')(that, worker, 1)
queue.push(42, function (err, result) {
if (err) { throw err }
console.log(this)
console.log('the result is', result)
})
function worker (arg, cb) {
console.log(this)
cb(null, 42 * 2)
}
API
- fastqueue()
- queue#push()
- queue#unshift()
- queue#pause()
- queue#resume()
- queue#idle()
- queue#length()
- queue#getQueue()
- queue#kill()
- queue#killAndDrain()
- queue#concurrency
- queue#drain
- queue#empty
- queue#saturated
fastqueue([that], worker, concurrency)
Creates a new queue.
Arguments:
that, optional context of theworkerfunction.worker, worker function, it would be called withthatasthis,
if that is specified.concurrency, number of concurrent tasks that could be executed in
parallel.
queue.push(task, done)
Add a task at the end of the queue. done(err, result) will be called
when the task was processed.
queue.unshift(task, done)
Add a task at the beginning of the queue. done(err, result) will be called
when the task was processed.
queue.pause()
Pause the processing of tasks. Currently worked tasks are not
stopped.
queue.resume()
Resume the processing of tasks.
queue.idle()
Returns false if there are tasks being processed or waiting to be processed.
true otherwise.
queue.length()
Returns the number of tasks waiting to be processed (in the queue).
queue.getQueue()
Returns all the tasks be processed (in the queue). Returns empty array when there are no tasks
queue.kill()
Removes all tasks waiting to be processed, and reset drain to an empty
function.
queue.killAndDrain()
Same than kill but the drain function will be called before reset to empty.
queue.concurrency
Property that returns the number of concurrent tasks that could be executed in
parallel. It can be altered at runtime.
queue.drain
Function that will be called when the last
item from the queue has been processed by a worker.
It can be altered at runtime.
queue.empty
Function that will be called when the last
item from the queue has been assigned to a worker.
It can be altered at runtime.
queue.saturated
Function that will be called when the queue hits the concurrency
limit.
It can be altered at runtime.
License
ISC