Axios is a popular, promise-based HTTP client that sports an easy-to-use API and can be used in both the browser and Node.js.
As people move away from jQuery in favor of improved native DOM APIs, or front-end UI libraries like React and Vue.js, including it purely for its $.ajax functionality makes less sense.
Axios vs Fetch
As you’re probably aware, modern browsers ship with the newer Fetch API built in, so why not just use that? There are several differences between the two that many feel gives Axios the edge.
One such difference is in how the two libraries treat HTTP error codes. When using Fetch, if the server returns a 4xx or 5xx series error, your catch() callback won’t be triggered and it is down to the developer to check the response status code to determine if the request was successful. Axios, on the other hand, will reject the request promise if one of these status codes is returned.
Another small difference, which often trips up developers new to the API, is that Fetch doesn’t automatically send cookies back to the server when making a request. It’s necessary to explicitly pass an option for them to be included. Axios has your back here.
One difference that may end up being a show-stopper for some is progress updates on uploads/downloads. As Axios is built on top of the older XHR API, you’re able to register callback functions for onUploadProgress and onDownloadProgress to display the percentage complete in your app’s UI. Currently, Fetch has no support for doing this.
Note: there are versions of the Fetch API available for Node but, in my opinion, the other features Axios provides give it the edge.
As you might expect, the most common way to install Axios is via the npm package manager:
npm i axios
and include it in your code where needed:
// ES2015 style import
import axios from ‘axios’;
// Node.js style require
const axios = require(‘axios’);
If you’re not using some kind of module bundler (e.g. webpack), then you can always pull in the library from a CDN in the traditional way: