throat 3.0.0

Throttle the parallelism of an asynchronous (promise returning) function / functions

Homepage: https://github.com/ForbesLindesay/throat

Platform: npm

Language: JavaScript

License: MIT

Keywords: promise, aplus, then, throttle, concurrency, parallelism, limit

View on registry: https://www.npmjs.com/package/throat

Direct download link: https://registry.npmjs.org/throat/-/throat-3.0.0.tgz

Install: npm install [email protected]


throat

Throttle the parallelism of an asynchronous, promise returning, function / functions. This has special utility when you set the concurrency to 1. That way you get a mutually exclusive lock.

Build Status Coverage Status Dependency Status NPM version

Sauce Test Status

Installation

npm install throat

API

throat(concurrency)

This returns a function that acts a bit like a lock (exactly as a lock if concurrency is 1).

Example, only 2 of the following functions will execute at any one time:

// with polyfill or in iojs
require('promise/polyfill')
var throat = require('throat')(2)
// alternatively provide your own promise implementation
var throat = require('throat')(require('promise'))(2)

var resA = throat(function () {
  //async stuff
  return promise
})
var resA = throat(function () {
  //async stuff
  return promise
})
var resA = throat(function () {
  //async stuff
  return promise
})
var resA = throat(function () {
  //async stuff
  return promise
})
var resA = throat(function () {
  //async stuff
  return promise
})

throat(concurrency, worker)

This returns a function that is an exact copy of worker except that it will only execute up to concurrency times in parallel before further requests are queued:

// with polyfill or in iojs
require('promise/polyfill')
var throat = require('throat')
// alternatively provide your own promise implementation
var throat = require('throat')(require('promise'))

var input = ['fileA.txt', 'fileB.txt', 'fileC.txt', 'fileD.txt']
var data = Promise.all(input.map(throat(2, function (fileName) {
  return readFile(fileName)
})))

Only 2 files will be read at a time, sometimes limiting parallelism in this way can improve scalability.

License

MIT

Releases

  • 3.0.0 - June 01, 2016 10:43
  • 2.0.2 - February 16, 2015 09:39
  • 2.0.1 - February 14, 2015 12:55
  • 2.0.0 - February 14, 2015 11:40
  • 1.0.0 - July 27, 2013 01:28
  • 0.0.0 - December 23, 2012 00:17

Project Statistics

SourceRank 18
Dependencies 0
Dependent projects 73
Dependent repositories 1.59K
Total releases 6
Latest release
First release
Stars 178
Forks 9
Watchers 5
Contributors 1
Repo Size: 15.6 KB

Top Contributors See all

Forbes Lindesay

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