You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
hjl 9372f6120a
add file
10 months ago
..
LICENSE add file 10 months ago
README.md add file 10 months ago
index.d.ts add file 10 months ago
index.js add file 10 months ago
index.js.flow add file 10 months ago
package.json add file 10 months ago

README.md

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.

Professionally supported throat is now available

Build Status Coverage Status Dependency Status NPM version Greenkeeper badge

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:

const throat = require('throat')(2);
// alternatively provide your own promise implementation
const throat = require('throat')(require('promise'))(2);
const promise = Promise.resolve();

const resA = throat(() => /* async stuff... */ promise);
const resB = throat(() => /* async stuff... */ promise);
const resC = throat(() => /* async stuff... */ promise);
const resD = throat(() => /* async stuff... */ promise);
const resE = throat(() => /* async stuff... */ 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:

const throat = require('throat');
// alternatively provide your own promise implementation
const throat = require('throat')(require('promise'));

const input = ['fileA.txt', 'fileB.txt', 'fileC.txt', 'fileD.txt'];
const data = Promise.all(input.map(throat(2, fileName => readFile(fileName))));

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

Security contact information

To report a security vulnerability, please use the Tidelift security contact. Tidelift will coordinate the fix and disclosure.

License

MIT