throat

What is throat?

The 'throat' npm package is a utility for limiting the number of concurrent asynchronous operations. It is particularly useful when you need to control the rate of operations to avoid overwhelming resources or hitting rate limits.

What are throat's main functionalities?

Limit Concurrent Promises

This feature allows you to limit the number of concurrent promises. In this example, only 2 tasks will run concurrently.

const throat = require('throat')(2);

const tasks = [
  () => new Promise(resolve => setTimeout(() => resolve('Task 1'), 1000)),
  () => new Promise(resolve => setTimeout(() => resolve('Task 2'), 500)),
  () => new Promise(resolve => setTimeout(() => resolve('Task 3'), 300)),
  () => new Promise(resolve => setTimeout(() => resolve('Task 4'), 200))
];

Promise.all(tasks.map(throat(task => task()))).then(results => {
  console.log(results); // ['Task 1', 'Task 2', 'Task 3', 'Task 4']
});

Limit Concurrent Function Calls

This feature allows you to limit the number of concurrent function calls. In this example, only 1 task will run at a time.

const throat = require('throat')(1);

const task = (name, delay) => () => new Promise(resolve => setTimeout(() => resolve(name), delay));

const tasks = [
  task('Task 1', 1000),
  task('Task 2', 500),
  task('Task 3', 300),
  task('Task 4', 200)
];

Promise.all(tasks.map(throat(task => task()))).then(results => {
  console.log(results); // ['Task 1', 'Task 2', 'Task 3', 'Task 4']
});

Other packages similar to throat

p-limit

The 'p-limit' package provides similar functionality by limiting the number of concurrent promises. It offers a more modern API and is often used in conjunction with other promise utilities from the 'p-*' family of packages.

async

The 'async' package is a comprehensive utility library for asynchronous operations. It includes a 'queue' function that can limit the number of concurrent tasks, among many other features. It is more feature-rich but also more complex than 'throat'.

promise-limit

The 'promise-limit' package is another alternative for limiting the number of concurrent promises. It is lightweight and straightforward, similar to 'throat', but with a slightly different API.

README

throat

Throttle a collection of promise returning functions