What is lodash.throttle?
The lodash.throttle package is a utility that allows you to rate-limit a function's execution. This can be particularly useful for controlling the rate at which a function that would otherwise be called continuously or very frequently is actually invoked. This is often used in scenarios such as handling scroll, resize, or mousemove events in the browser, where the event can fire many times per second, but you only want to execute a handler function at a controlled rate.
What are lodash.throttle's main functionalities?
Rate-limiting function calls
This feature allows you to limit the number of times a function can be called over time. In the code sample, the `saveInput` function is throttled so that it can only be executed once every 1000 milliseconds, even if the 'input' event is fired more frequently than that.
const _ = require('lodash.throttle');
function saveInput() {
console.log('Input saved');
}
// Only allow the `saveInput` function to be called once every 1000 milliseconds
const throttledSaveInput = _.throttle(saveInput, 1000);
window.addEventListener('input', throttledSaveInput);
Configuring leading and trailing calls
This feature allows you to control whether the throttled function should be invoked on the leading and/or trailing edge of the wait timeout. In the code sample, the `updatePosition` function is configured to be called at the start of the throttle period (leading edge) but not at the end (trailing edge).
const _ = require('lodash.throttle');
function updatePosition() {
console.log('Updating position');
}
// Configure the throttle to invoke on the leading edge of the timeout, but not on the trailing edge.
const throttledUpdatePosition = _.throttle(updatePosition, 2000, {
leading: true,
trailing: false
});
window.addEventListener('scroll', throttledUpdatePosition);
Other packages similar to lodash.throttle
throttle-debounce
The throttle-debounce package provides both throttle and debounce functions. It is similar to lodash.throttle but also includes a debounce function, which is useful for delaying a function's execution until after a certain amount of time has elapsed since the last time it was invoked.
bottleneck
Bottleneck is a powerful rate-limiting library that not only throttles functions but also manages their execution to prevent server overload. It provides more advanced features like clustering support and priority options, making it more suitable for complex rate-limiting scenarios compared to lodash.throttle.
p-throttle
p-throttle is a throttle function that returns a promise and is designed to work with async functions. It is similar to lodash.throttle but is promise-based, making it a better fit for use in modern asynchronous JavaScript code.
lodash.throttle v4.1.0
The lodash method _.throttle
exported as a Node.js module.
Installation
Using npm:
$ {sudo -H} npm i -g npm
$ npm i --save lodash.throttle
In Node.js:
var throttle = require('lodash.throttle');
See the documentation or package source for more details.