axios vs fetch-mock vs react-query vs use-http

HTTP Client and Data Fetching Strategies in Modern React Applications

axios, fetch-mock, react-query, and use-http address different aspects of network communication in frontend applications. axios is a promise-based HTTP client that works in both browser and Node.js environments, offering a consistent API for making requests. fetch-mock is a testing utility designed to intercept and mock calls to the native fetch API, primarily used in unit and integration tests. react-query is a powerful data synchronization library that handles server state management, caching, background updates, and request deduplication for React applications. use-http is a lightweight React hook that wraps the native fetch API with a hook-based interface, providing basic loading and error states without advanced caching or synchronization features.

Npm Package Weekly Downloads Trend

3 Years

Github Stars Ranking

Stat Detail

Package	Downloads	Stars	Size	Issues	Publish	License
Package	Downloads	Stars	Size	Issues	Publish	License
axios	0	108,593	2.42 MB	344	8 days ago	MIT
fetch-mock	0	1,310	157 kB	5	4 months ago	MIT
react-query	0	48,726	2.26 MB	175	3 years ago	MIT
use-http	0	2,306	224 kB	91	3 years ago	MIT

HTTP Client and Data Fetching Strategies: axios vs fetch-mock vs react-query vs use-http

When building modern web applications, developers face decisions not just about how to make HTTP requests, but also how to manage loading states, cache responses, handle errors, and test network behavior. The packages axios, fetch-mock, react-query, and use-http each solve distinct problems in this space. Let’s break down their roles, capabilities, and trade-offs.

📡 Core Purpose: What Problem Does Each Package Solve?

axios is a full-featured HTTP client. It abstracts the underlying transport (XMLHttpRequest in browsers, HTTP module in Node.js) and provides a clean, promise-based API for making requests.

// axios: Make a GET request
import axios from 'axios';

const response = await axios.get('/api/user', {
  headers: { Authorization: 'Bearer token' }
});
console.log(response.data);

fetch-mock is not a client — it’s a testing tool. It replaces the global fetch function during tests so you can simulate network responses.

// fetch-mock: Mock a fetch call in a test
import fetchMock from 'fetch-mock';

fetchMock.get('/api/user', { name: 'Alice' });

// Later in test
const res = await fetch('/api/user');
const data = await res.json(); // { name: 'Alice' }

react-query manages server state, not just requests. It caches responses, tracks query status, and automatically revalidates data in the background.

// react-query: Fetch and cache user data
import { useQuery } from '@tanstack/react-query';

function UserProfile() {
  const { data, isLoading, error } = useQuery({
    queryKey: ['user'],
    queryFn: () => fetch('/api/user').then(res => res.json())
  });

  if (isLoading) return <div>Loading...</div>;
  if (error) return <div>Error!</div>;
  return <div>Hello, {data.name}</div>;
}

use-http is a thin React hook wrapper around fetch. It gives you loading and error states but doesn’t cache or deduplicate requests.

// use-http: Basic hook for fetching
import useFetch from 'use-http';

function UserProfile() {
  const { loading, error, data } = useFetch('/api/user', {}, []);

  if (loading) return <div>Loading...</div>;
  if (error) return <div>Error!</div>;
  return <div>Hello, {data.name}</div>;
}

⚠️ Note: fetch-mock is only for testing. Never include it in production bundles.

🔁 Request Execution and Cancellation

All four packages interact with network requests, but only some support cancellation.

axios supports cancellation via AbortController or its legacy CancelToken API.

// axios cancellation
const controller = new AbortController();
axios.get('/api/data', { signal: controller.signal });
controller.abort(); // cancels the request

fetch-mock doesn’t execute real requests, so cancellation isn’t relevant. However, it respects the signal passed to fetch in mocked calls.

// fetch-mock respects AbortSignal
fetchMock.get('/api/test', { body: { ok: true } });
const controller = new AbortController();
fetch('/api/test', { signal: controller.signal });
// Mocked response still honors signal if abort() is called

react-query automatically cancels ongoing queries when a component unmounts or a query key changes, using AbortController under the hood.

// react-query auto-cancels
const { data } = useQuery({
  queryKey: ['user', userId],
  queryFn: ({ signal }) =>
    fetch(`/api/user/${userId}`, { signal }).then(res => res.json())
});
// If userId changes or component unmounts, previous request is aborted

use-http also supports AbortController via options.

// use-http with abort
const { data } = useFetch('/api/user', {
  method: 'GET',
  cachePolicy: 'no-cache'
}, {
  abortOnUnmount: true // auto-aborts on unmount
});

🧪 Testing Network Behavior

Only fetch-mock is designed for testing, but others influence testability.

axios: Harder to mock because it doesn’t use the native fetch. You typically mock the axios module itself.

// Mocking axios in tests (Jest example)
jest.mock('axios');
axios.get.mockResolvedValue({ data: { name: 'Bob' } });

fetch-mock: Built for mocking fetch. Works seamlessly with any code that uses native fetch.

// fetch-mock in action
beforeEach(() => fetchMock.reset());
afterEach(() => fetchMock.restore());

it('handles user fetch', async () => {
  fetchMock.get('/api/user', { name: 'Charlie' });
  render(<UserProfile />);
  await screen.findByText('Charlie');
});

react-query: Provides excellent test utilities. You can wrap components in a QueryClientProvider with a custom client that uses mocked fetchers.

// Testing react-query components
const queryClient = new QueryClient({
  defaultOptions: { queries: { retry: false } }
});

render(
  <QueryClientProvider client={queryClient}>
    <UserProfile />
  </QueryClientProvider>
);
// Mock the actual fetch inside queryFn during test setup

use-http: Since it uses fetch, it can be tested with fetch-mock.

// use-http + fetch-mock
fetchMock.get('/api/user', { name: 'Dana' });
render(<UserProfile />);
await screen.findByText('Dana');

🗃️ Caching and Data Synchronization

This is where react-query stands apart.

axios has no built-in caching. You must implement it yourself or use external libraries.

fetch-mock doesn’t apply — it’s for tests only.

react-query provides:

Automatic caching by query key
Stale-while-revalidate behavior
Background refetching on window focus or reconnect
Pagination and infinite scroll support
Mutation handling with rollback and optimistic updates

// react-query caching example
const { data } = useQuery({
  queryKey: ['posts'],
  queryFn: fetchPosts,
  staleTime: 10000 // consider fresh for 10s
});
// Subsequent mounts reuse cached data instantly

use-http offers no caching. Every hook call triggers a new request unless you manually memoize or manage state externally.

// use-http: No caching — re-fetches on every render if not controlled
const { data } = useFetch('/api/posts'); // Fetches anew each time

🧩 Integration with React Patterns

axios is framework-agnostic. You’ll often wrap it in useEffect or custom hooks.

// axios in a useEffect
useEffect(() => {
  axios.get('/api/data').then(setData);
}, []);

react-query is built for React. It leverages context, suspense, and concurrent rendering patterns.

// react-query with Suspense (optional)
<Suspense fallback="Loading...">
  <UserProfile />
</Suspense>

use-http is React-native via hooks but lacks advanced integrations like react-query’s devtools or mutation APIs.

// use-http basic usage
const request = useFetch();
const createUser = () => request.post('/api/users', userData);

🛑 Error Handling Approaches

axios throws on HTTP 4xx/5xx by default, which you catch with .catch() or try/catch.

try {
  await axios.get('/api/fail');
} catch (error) {
  console.log(error.response.status); // e.g., 404
}

react-query captures errors and exposes them via the error property, keeping UI logic declarative.

const { error } = useQuery({ queryKey: ['data'], queryFn: fetchData });
if (error) return <ErrorMessage message={error.message} />;

use-http also exposes errors directly in the hook return value.

const { error } = useFetch('/api/data');
if (error) return <div>Failed: {error.message}</div>;

fetch-mock lets you simulate errors in tests.

fetchMock.get('/api/bad', 500); // returns 500 error

📊 When to Use Which?

Scenario	Recommended Package
Need a reliable HTTP client for browser + Node.js	`axios`
Writing tests that involve `fetch`	`fetch-mock`
Building a data-heavy React app with caching, background updates, and mutations	`react-query`
Simple React app needing basic fetch + loading states, no caching	`use-http`

💡 Final Thoughts

These packages aren’t competitors — they serve different layers of the networking stack:

fetch-mock lives in your test suite.
axios is a general-purpose HTTP client.
use-http is a minimal React hook for fetch.
react-query is a full server-state manager for React.

In practice, you might even combine them: use axios as the underlying client inside react-query’s queryFn, and use fetch-mock to test components that rely on use-http or native fetch.

Choose based on whether you need transport, testing, state management, or simplicity — not just “which one makes HTTP requests.”

How to Choose: axios vs fetch-mock vs react-query vs use-http

axios:
Choose axios when you need a robust, cross-platform HTTP client with built-in support for request/response interception, automatic JSON transformation, and cancellation. It’s ideal for projects that require consistent networking logic across browser and Node.js environments, or when working with APIs that expect specific headers, authentication flows, or error handling patterns that are easier to configure globally via interceptors.
fetch-mock:
Choose fetch-mock exclusively for testing scenarios where you need to mock the native fetch API. It should not be used in production code. Use it when writing unit or integration tests for components or utilities that rely on fetch, allowing you to simulate network responses, verify request payloads, and test error conditions without hitting real endpoints.
react-query:
Choose react-query when building data-intensive React applications that require sophisticated server state management — including caching, background refetching, pagination, mutations with optimistic updates, and automatic deduplication of concurrent requests. It shines in apps where data consistency, performance, and user experience around loading and stale states are critical, such as dashboards, admin panels, or collaborative tools.
use-http:
Choose use-http for lightweight React projects that need a simple hook-based wrapper around fetch with minimal overhead. It’s suitable when you don’t require advanced caching, background syncing, or complex mutation patterns, but still want convenient access to loading, error, and data states directly in your components. Avoid it if your app will grow to need robust data synchronization or if you’re already using a more comprehensive solution like react-query.

Popular Comparisons

axios

fetch-mock

react-query

use-http

README for axios

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Promise based HTTP client for the browser and node.js

Website • Documentation

npm bundle size npm downloads

Features

Browser Requests: Make XMLHttpRequests directly from the browser.
Node.js Requests: Make http requests from Node.js environments.
Promise-based: Fully supports the Promise API for easier asynchronous code.
Interceptors: Intercept requests and responses to add custom logic or transform data.
Data Transformation: Transform request and response data automatically.
Request Cancellation: Cancel requests using built-in mechanisms.
Automatic JSON Handling: Automatically serializes and parses JSON data.
Form Serialization: 🆕 Automatically serializes data objects to multipart/form-data or x-www-form-urlencoded formats.
XSRF Protection: Client-side support to protect against Cross-Site Request Forgery.

Browser Support

Chrome	Firefox	Safari	Opera	Edge

Latest ✔	Latest ✔	Latest ✔	Latest ✔	Latest ✔

Installing

Package manager

Using npm:

$ npm install axios

Using bower:

$ bower install axios

Using yarn:

$ yarn add axios

Using pnpm:

$ pnpm add axios

Using bun:

$ bun add axios

Once the package is installed, you can import the library using import or require approach:

import axios, { isCancel, AxiosError } from "axios";

You can also use the default export, since the named export is just a re-export from the Axios factory:

import axios from "axios";

console.log(axios.isCancel("something"));

If you use require for importing, only the default export is available:

const axios = require("axios");

console.log(axios.isCancel("something"));

For some bundlers and some ES6 linters you may need to do the following:

import { default as axios } from "axios";

For cases where something went wrong when trying to import a module into a custom or legacy environment, you can try importing the module package directly:

const axios = require("axios/dist/browser/axios.cjs"); // browser commonJS bundle (ES2017)
// const axios = require('axios/dist/node/axios.cjs'); // node commonJS bundle (ES2017)

CDN

Using jsDelivr CDN (ES5 UMD browser module):

<script src="https://cdn.jsdelivr.net/npm/axios@1.13.2/dist/axios.min.js"></script>

Using unpkg CDN:

<script src="https://unpkg.com/axios@1.13.2/dist/axios.min.js"></script>

Example

import axios from "axios";
//const axios = require('axios'); // legacy way

try {
  const response = await axios.get("/user?ID=12345");
  console.log(response);
} catch (error) {
  console.error(error);
}

// Optionally the request above could also be done as
axios
  .get("/user", {
    params: {
      ID: 12345,
    },
  })
  .then(function (response) {
    console.log(response);
  })
  .catch(function (error) {
    console.log(error);
  })
  .finally(function () {
    // always executed
  });

// Want to use async/await? Add the `async` keyword to your outer function/method.
async function getUser() {
  try {
    const response = await axios.get("/user?ID=12345");
    console.log(response);
  } catch (error) {
    console.error(error);
  }
}

Note: async/await is part of ECMAScript 2017 and is not supported in Internet Explorer and older browsers, so use with caution.

Performing a POST request

const response = await axios.post("/user", {
  firstName: "Fred",
  lastName: "Flintstone",
});
console.log(response);

Performing multiple concurrent requests

function getUserAccount() {
  return axios.get("/user/12345");
}

function getUserPermissions() {
  return axios.get("/user/12345/permissions");
}

Promise.all([getUserAccount(), getUserPermissions()]).then(function (results) {
  const acct = results[0];
  const perm = results[1];
});

axios API

Requests can be made by passing the relevant config to axios.

axios(config)

// Send a POST request
axios({
  method: "post",
  url: "/user/12345",
  data: {
    firstName: "Fred",
    lastName: "Flintstone",
  },
});

// GET request for remote image in node.js
const response = await axios({
  method: "get",
  url: "https://bit.ly/2mTM3nY",
  responseType: "stream",
});
response.data.pipe(fs.createWriteStream("ada_lovelace.jpg"));

axios(url[, config])

// Send a GET request (default method)
axios("/user/12345");

Request method aliases

For convenience, aliases have been provided for all common request methods.

axios.request(config)

axios.get(url[, config])

axios.delete(url[, config])

axios.head(url[, config])

axios.options(url[, config])

axios.post(url[, data[, config]])

axios.put(url[, data[, config]])

axios.patch(url[, data[, config]])

NOTE

When using the alias methods url, method, and data properties don't need to be specified in config.

Concurrency (Deprecated)

Please use Promise.all to replace the below functions.

Helper functions for dealing with concurrent requests.

axios.all(iterable) axios.spread(callback)

Creating an instance

You can create a new instance of axios with a custom config.

axios.create([config])

const instance = axios.create({
  baseURL: "https://some-domain.com/api/",
  timeout: 1000,
  headers: { "X-Custom-Header": "foobar" },
});

Instance methods

The available instance methods are listed below. The specified config will be merged with the instance config.

axios#request(config)

axios#get(url[, config])

axios#delete(url[, config])

axios#head(url[, config])

axios#options(url[, config])

axios#post(url[, data[, config]])

axios#put(url[, data[, config]])

axios#patch(url[, data[, config]])

axios#getUri([config])

Request Config

These are the available config options for making requests. Only the url is required. Requests will default to GET if method is not specified.

{
  // `url` is the server URL that will be used for the request
  url: '/user',

  // `method` is the request method to be used when making the request
  method: 'get', // default

  // `baseURL` will be prepended to `url` unless `url` is absolute and the option `allowAbsoluteUrls` is set to true.
  // It can be convenient to set `baseURL` for an instance of axios to pass relative URLs
  // to the methods of that instance.
  baseURL: 'https://some-domain.com/api/',

  // `allowAbsoluteUrls` determines whether or not absolute URLs will override a configured `baseUrl`.
  // When set to true (default), absolute values for `url` will override `baseUrl`.
  // When set to false, absolute values for `url` will always be prepended by `baseUrl`.
  allowAbsoluteUrls: true,

  // `transformRequest` allows changes to the request data before it is sent to the server
  // This is only applicable for request methods 'PUT', 'POST', 'PATCH' and 'DELETE'
  // The last function in the array must return a string or an instance of Buffer, ArrayBuffer,
  // FormData or Stream
  // You may modify the headers object.
  transformRequest: [function (data, headers) {
    // Do whatever you want to transform the data

    return data;
  }],

  // `transformResponse` allows changes to the response data to be made before
  // it is passed to then/catch
  transformResponse: [function (data) {
    // Do whatever you want to transform the data

    return data;
  }],

  // `headers` are custom headers to be sent
  headers: {'X-Requested-With': 'XMLHttpRequest'},

  // `params` are the URL parameters to be sent with the request
  // Must be a plain object or a URLSearchParams object
  params: {
    ID: 12345
  },

  // `paramsSerializer` is an optional config that allows you to customize serializing `params`.
  paramsSerializer: {

    // Custom encoder function which sends key/value pairs in an iterative fashion.
    encode?: (param: string): string => { /* Do custom operations here and return transformed string */ },

    // Custom serializer function for the entire parameter. Allows the user to mimic pre 1.x behaviour.
    serialize?: (params: Record<string, any>, options?: ParamsSerializerOptions ),

    // Configuration for formatting array indexes in the params.
    indexes: false // Three available options: (1) indexes: null (leads to no brackets), (2) (default) indexes: false (leads to empty brackets), (3) indexes: true (leads to brackets with indexes).
  },

  // `data` is the data to be sent as the request body
  // Only applicable for request methods 'PUT', 'POST', 'DELETE', and 'PATCH'
  // When no `transformRequest` is set, it must be of one of the following types:
  // - string, plain object, ArrayBuffer, ArrayBufferView, URLSearchParams
  // - Browser only: FormData, File, Blob
  // - Node only: Stream, Buffer, FormData (form-data package)
  data: {
    firstName: 'Fred'
  },

  // syntax alternative to send data into the body
  // method post
  // only the value is sent, not the key
  data: 'Country=Brasil&City=Belo Horizonte',

  // `timeout` specifies the number of milliseconds before the request times out.
  // If the request takes longer than `timeout`, the request will be aborted.
  timeout: 1000, // default is `0` (no timeout)

  // `withCredentials` indicates whether or not cross-site Access-Control requests
  // should be made using credentials
  withCredentials: false, // default

  // `adapter` allows custom handling of requests which makes testing easier.
  // Return a promise and supply a valid response (see lib/adapters/README.md)
  adapter: function (config) {
    /* ... */
  },
  // Also, you can set the name of the built-in adapter, or provide an array with their names
  // to choose the first available in the environment
  adapter: 'xhr', // 'fetch' | 'http' | ['xhr', 'http', 'fetch']

  // `auth` indicates that HTTP Basic auth should be used, and supplies credentials.
  // This will set an `Authorization` header, overwriting any existing
  // `Authorization` custom headers you have set using `headers`.
  // Please note that only HTTP Basic auth is configurable through this parameter.
  // For Bearer tokens and such, use `Authorization` custom headers instead.
  auth: {
    username: 'janedoe',
    password: 's00pers3cret'
  },

  // `responseType` indicates the type of data that the server will respond with
  // options are: 'arraybuffer', 'document', 'json', 'text', 'stream'
  //   browser only: 'blob'
  responseType: 'json', // default

  // `responseEncoding` indicates encoding to use for decoding responses (Node.js only)
  // Note: Ignored for `responseType` of 'stream' or client-side requests
  // options are: 'ascii', 'ASCII', 'ansi', 'ANSI', 'binary', 'BINARY', 'base64', 'BASE64', 'base64url',
  // 'BASE64URL', 'hex', 'HEX', 'latin1', 'LATIN1', 'ucs-2', 'UCS-2', 'ucs2', 'UCS2', 'utf-8', 'UTF-8',
  // 'utf8', 'UTF8', 'utf16le', 'UTF16LE'
  responseEncoding: 'utf8', // default

  // `xsrfCookieName` is the name of the cookie to use as a value for the xsrf token
  xsrfCookieName: 'XSRF-TOKEN', // default

  // `xsrfHeaderName` is the name of the http header that carries the xsrf token value
  xsrfHeaderName: 'X-XSRF-TOKEN', // default

  // `undefined` (default) - set XSRF header only for the same origin requests
  withXSRFToken: boolean | undefined | ((config: InternalAxiosRequestConfig) => boolean | undefined),

  // `onUploadProgress` allows handling of progress events for uploads
  // browser & node.js
  onUploadProgress: function ({loaded, total, progress, bytes, estimated, rate, upload = true}) {
    // Do whatever you want with the Axios progress event
  },

  // `onDownloadProgress` allows handling of progress events for downloads
  // browser & node.js
  onDownloadProgress: function ({loaded, total, progress, bytes, estimated, rate, download = true}) {
    // Do whatever you want with the Axios progress event
  },

  // `maxContentLength` defines the max size of the http response content in bytes allowed in node.js
  maxContentLength: 2000,

  // `maxBodyLength` (Node only option) defines the max size of the http request content in bytes allowed
  maxBodyLength: 2000,

  // `validateStatus` defines whether to resolve or reject the promise for a given
  // HTTP response status code. If `validateStatus` returns `true` (or is set to `null`
  // or `undefined`), the promise will be resolved; otherwise, the promise will be
  // rejected.
  validateStatus: function (status) {
    return status >= 200 && status < 300; // default
  },

  // `maxRedirects` defines the maximum number of redirects to follow in node.js.
  // If set to 0, no redirects will be followed.
  maxRedirects: 21, // default

  // `beforeRedirect` defines a function that will be called before redirect.
  // Use this to adjust the request options upon redirecting,
  // to inspect the latest response headers,
  // or to cancel the request by throwing an error
  // If maxRedirects is set to 0, `beforeRedirect` is not used.
  beforeRedirect: (options, { headers }) => {
    if (options.hostname === "example.com") {
      options.auth = "user:password";
    }
  },

  // `socketPath` defines a UNIX Socket to be used in node.js.
  // e.g. '/var/run/docker.sock' to send requests to the docker daemon.
  // Only either `socketPath` or `proxy` can be specified.
  // If both are specified, `socketPath` is used.
  socketPath: null, // default

  // `transport` determines the transport method that will be used to make the request.
  // If defined, it will be used. Otherwise, if `maxRedirects` is 0,
  // the default `http` or `https` library will be used, depending on the protocol specified in `protocol`.
  // Otherwise, the `httpFollow` or `httpsFollow` library will be used, again depending on the protocol,
  // which can handle redirects.
  transport: undefined, // default

  // `httpAgent` and `httpsAgent` define a custom agent to be used when performing http
  // and https requests, respectively, in node.js. This allows options to be added like
  // `keepAlive` that are not enabled by default before Node.js v19.0.0. After Node.js
  // v19.0.0, you no longer need to customize the agent to enable `keepAlive` because
  // `http.globalAgent` has `keepAlive` enabled by default.
  httpAgent: new http.Agent({ keepAlive: true }),
  httpsAgent: new https.Agent({ keepAlive: true }),

  // `proxy` defines the hostname, port, and protocol of the proxy server.
  // You can also define your proxy using the conventional `http_proxy` and
  // `https_proxy` environment variables. If you are using environment variables
  // for your proxy configuration, you can also define a `no_proxy` environment
  // variable as a comma-separated list of domains that should not be proxied.
  // Use `false` to disable proxies, ignoring environment variables.
  // `auth` indicates that HTTP Basic auth should be used to connect to the proxy, and
  // supplies credentials.
  // This will set a `Proxy-Authorization` header, overwriting any existing
  // `Proxy-Authorization` custom headers you have set using `headers`.
  // If the proxy server uses HTTPS, then you must set the protocol to `https`.
  proxy: {
    protocol: 'https',
    host: '127.0.0.1',
    // hostname: '127.0.0.1' // Takes precedence over 'host' if both are defined
    port: 9000,
    auth: {
      username: 'mikeymike',
      password: 'rapunz3l'
    }
  },

  // `cancelToken` specifies a cancel token that can be used to cancel the request
  // (see Cancellation section below for details)
  cancelToken: new CancelToken(function (cancel) {
  }),

  // an alternative way to cancel Axios requests using AbortController
  signal: new AbortController().signal,

  // `decompress` indicates whether or not the response body should be decompressed
  // automatically. If set to `true` will also remove the 'content-encoding' header
  // from the responses objects of all decompressed responses
  // - Node only (XHR cannot turn off decompression)
  decompress: true, // default

  // `insecureHTTPParser` boolean.
  // Indicates where to use an insecure HTTP parser that accepts invalid HTTP headers.
  // This may allow interoperability with non-conformant HTTP implementations.
  // Using the insecure parser should be avoided.
  // see options https://nodejs.org/dist/latest-v12.x/docs/api/http.html#http_http_request_url_options_callback
  // see also https://nodejs.org/en/blog/vulnerability/february-2020-security-releases/#strict-http-header-parsing-none
  insecureHTTPParser: undefined, // default

  // transitional options for backward compatibility that may be removed in the newer versions
  transitional: {
    // silent JSON parsing mode
    // `true`  - ignore JSON parsing errors and set response.data to null if parsing failed (old behaviour)
    // `false` - throw SyntaxError if JSON parsing failed (Note: responseType must be set to 'json')
    silentJSONParsing: true, // default value for the current Axios version

    // try to parse the response string as JSON even if `responseType` is not 'json'
    forcedJSONParsing: true,

    // throw ETIMEDOUT error instead of generic ECONNABORTED on request timeouts
    clarifyTimeoutError: false,

    // use the legacy interceptor request/response ordering
    legacyInterceptorReqResOrdering: true, // default
  },

  env: {
    // The FormData class to be used to automatically serialize the payload into a FormData object
    FormData: window?.FormData || global?.FormData
  },

  formSerializer: {
      visitor: (value, key, path, helpers) => {}; // custom visitor function to serialize form values
      dots: boolean; // use dots instead of brackets format
      metaTokens: boolean; // keep special endings like {} in parameter key
      indexes: boolean; // array indexes format null - no brackets, false - empty brackets, true - brackets with indexes
  },

  // http adapter only (node.js)
  maxRate: [
    100 * 1024, // 100KB/s upload limit,
    100 * 1024  // 100KB/s download limit
  ]
}

Response Schema

The response to a request contains the following information.

{
  // `data` is the response that was provided by the server
  data: {},

  // `status` is the HTTP status code from the server response
  status: 200,

  // `statusText` is the HTTP status message from the server response
  statusText: 'OK',

  // `headers` the HTTP headers that the server responded with
  // All header names are lowercase and can be accessed using the bracket notation.
  // Example: `response.headers['content-type']`
  headers: {},

  // `config` is the config that was provided to `axios` for the request
  config: {},

  // `request` is the request that generated this response
  // It is the last ClientRequest instance in node.js (in redirects)
  // and an XMLHttpRequest instance in the browser
  request: {}
}

When using then, you will receive the response as follows:

const response = await axios.get("/user/12345");
console.log(response.data);
console.log(response.status);
console.log(response.statusText);
console.log(response.headers);
console.log(response.config);

When using catch, or passing a rejection callback as second parameter of then, the response will be available through the error object as explained in the Handling Errors section.

Config Defaults

You can specify config defaults that will be applied to every request.

Global axios defaults

axios.defaults.baseURL = "https://api.example.com";

// Important: If axios is used with multiple domains, the AUTH_TOKEN will be sent to all of them.
// See below for an example using Custom instance defaults instead.
axios.defaults.headers.common["Authorization"] = AUTH_TOKEN;

axios.defaults.headers.post["Content-Type"] =
  "application/x-www-form-urlencoded";

Custom instance defaults

// Set config defaults when creating the instance
const instance = axios.create({
  baseURL: "https://api.example.com",
});

// Alter defaults after instance has been created
instance.defaults.headers.common["Authorization"] = AUTH_TOKEN;

Config order of precedence

Config will be merged with an order of precedence. The order is library defaults found in lib/defaults/index.js, then defaults property of the instance, and finally config argument for the request. The latter will take precedence over the former. Here's an example.

// Create an instance using the config defaults provided by the library
// At this point the timeout config value is `0` as is the default for the library
const instance = axios.create();

// Override timeout default for the library
// Now all requests using this instance will wait 2.5 seconds before timing out
instance.defaults.timeout = 2500;

// Override timeout for this request as it's known to take a long time
instance.get("/longRequest", {
  timeout: 5000,
});

Interceptors

You can intercept requests or responses before methods like .get() or .post() resolve their promises (before code inside then or catch, or after await)

const instance = axios.create();

// Add a request interceptor
instance.interceptors.request.use(
  function (config) {
    // Do something before the request is sent
    return config;
  },
  function (error) {
    // Do something with the request error
    return Promise.reject(error);
  },
);

// Add a response interceptor
instance.interceptors.response.use(
  function (response) {
    // Any status code that lies within the range of 2xx causes this function to trigger
    // Do something with response data
    return response;
  },
  function (error) {
    // Any status codes that fall outside the range of 2xx cause this function to trigger
    // Do something with response error
    return Promise.reject(error);
  },
);

If you need to remove an interceptor later you can.

const instance = axios.create();
const myInterceptor = instance.interceptors.request.use(function () {
  /*...*/
});
axios.interceptors.request.eject(myInterceptor);

You can also clear all interceptors for requests or responses.

const instance = axios.create();
instance.interceptors.request.use(function () {
  /*...*/
});
instance.interceptors.request.clear(); // Removes interceptors from requests
instance.interceptors.response.use(function () {
  /*...*/
});
instance.interceptors.response.clear(); // Removes interceptors from responses

You can add interceptors to a custom instance of axios.

const instance = axios.create();
instance.interceptors.request.use(function () {
  /*...*/
});

When you add request interceptors, they are presumed to be asynchronous by default. This can cause a delay in the execution of your axios request when the main thread is blocked (a promise is created under the hood for the interceptor and your request gets put at the bottom of the call stack). If your request interceptors are synchronous you can add a flag to the options object that will tell axios to run the code synchronously and avoid any delays in request execution.

axios.interceptors.request.use(
  function (config) {
    config.headers.test = "I am only a header!";
    return config;
  },
  null,
  { synchronous: true },
);

If you want to execute a particular interceptor based on a runtime check, you can add a runWhen function to the options object. The request interceptor will not be executed if and only if the return of runWhen is false. The function will be called with the config object (don't forget that you can bind your own arguments to it as well.) This can be handy when you have an asynchronous request interceptor that only needs to run at certain times.

function onGetCall(config) {
  return config.method === "get";
}
axios.interceptors.request.use(
  function (config) {
    config.headers.test = "special get headers";
    return config;
  },
  null,
  { runWhen: onGetCall },
);

Note: The options parameter(having synchronous and runWhen properties) is only supported for request interceptors at the moment.

Interceptor Execution Order

Important: Interceptors have different execution orders depending on their type!

Request interceptors are executed in reverse order (LIFO - Last In, First Out). This means the last interceptor added is executed first.

Response interceptors are executed in the order they were added (FIFO - First In, First Out). This means the first interceptor added is executed first.

Example:

const instance = axios.create();

const interceptor = (id) => (base) => {
  console.log(id);
  return base;
};

instance.interceptors.request.use(interceptor("Request Interceptor 1"));
instance.interceptors.request.use(interceptor("Request Interceptor 2"));
instance.interceptors.request.use(interceptor("Request Interceptor 3"));
instance.interceptors.response.use(interceptor("Response Interceptor 1"));
instance.interceptors.response.use(interceptor("Response Interceptor 2"));
instance.interceptors.response.use(interceptor("Response Interceptor 3"));

// Console output:
// Request Interceptor 3
// Request Interceptor 2
// Request Interceptor 1
// [HTTP request is made]
// Response Interceptor 1
// Response Interceptor 2
// Response Interceptor 3

Multiple Interceptors

Given that you add multiple response interceptors and when the response was fulfilled

then each interceptor is executed
then they are executed in the order they were added
then only the last interceptor's result is returned
then every interceptor receives the result of its predecessor
and when the fulfillment-interceptor throws
- then the following fulfillment-interceptor is not called
- then the following rejection-interceptor is called
- once caught, another following fulfill-interceptor is called again (just like in a promise chain).

Read the interceptor tests to see all this in code.

Error Types

There are many different axios error messages that can appear which can provide basic information about the specifics of the error and where opportunities may lie in debugging.

The general structure of axios errors is as follows:

Property	Definition
message	A quick summary of the error message and the status it failed with.
name	This defines where the error originated from. For axios, it will always be an 'AxiosError'.
stack	Provides the stack trace of the error.
config	An axios config object with specific instance configurations defined by the user from when the request was made
code	Represents an axios identified error. The table below lists specific definitions for internal axios error.
status	HTTP response status code. See here for common HTTP response status code meanings.

Below is a list of potential axios identified error:

Code	Definition
ERR_BAD_OPTION_VALUE	Invalid value provided in axios configuration.
ERR_BAD_OPTION	Invalid option provided in axios configuration.
ERR_NOT_SUPPORT	Feature or method not supported in the current axios environment.
ERR_DEPRECATED	Deprecated feature or method used in axios.
ERR_INVALID_URL	Invalid URL provided for axios request.
ECONNABORTED	Typically indicates that the request has been timed out (unless `transitional.clarifyTimeoutError` is set) or aborted by the browser or its plugin.
ERR_CANCELED	Feature or method is canceled explicitly by the user using an AbortSignal (or a CancelToken).
ETIMEDOUT	Request timed out due to exceeding the default axios timelimit. `transitional.clarifyTimeoutError` must be set to `true`, otherwise a generic `ECONNABORTED` error will be thrown instead.
ERR_NETWORK	Network-related issue. In the browser, this error can also be caused by a CORS or Mixed Content policy violation. The browser does not allow the JS code to clarify the real reason for the error caused by security issues, so please check the console.
ERR_FR_TOO_MANY_REDIRECTS	Request is redirected too many times; exceeds max redirects specified in axios configuration.
ERR_BAD_RESPONSE	Response cannot be parsed properly or is in an unexpected format. Usually related to a response with `5xx` status code.
ERR_BAD_REQUEST	The request has an unexpected format or is missing required parameters. Usually related to a response with `4xx` status code.

Handling Errors

The default behavior is to reject every response that returns with a status code that falls out of the range of 2xx and treat it as an error.

axios.get("/user/12345").catch(function (error) {
  if (error.response) {
    // The request was made and the server responded with a status code
    // that falls out of the range of 2xx
    console.log(error.response.data);
    console.log(error.response.status);
    console.log(error.response.headers);
  } else if (error.request) {
    // The request was made but no response was received
    // `error.request` is an instance of XMLHttpRequest in the browser and an instance of
    // http.ClientRequest in node.js
    console.log(error.request);
  } else {
    // Something happened in setting up the request that triggered an Error
    console.log("Error", error.message);
  }
  console.log(error.config);
});

Using the validateStatus config option, you can override the default condition (status >= 200 && status < 300) and define HTTP code(s) that should throw an error.

axios.get("/user/12345", {
  validateStatus: function (status) {
    return status < 500; // Resolve only if the status code is less than 500
  },
});

Using toJSON you get an object with more information about the HTTP error.

axios.get("/user/12345").catch(function (error) {
  console.log(error.toJSON());
});

Handling Timeouts

async function fetchWithTimeout() {
  try {
    const response = await axios.get("https://example.com/data", {
      timeout: 5000, // 5 seconds
    });

    console.log("Response:", response.data);
  } catch (error) {
    if (axios.isAxiosError(error) && error.code === "ECONNABORTED") {
      console.error("❌ Request timed out!");
    } else {
      console.error("❌ Error:", error.message);
    }
  }
}

Cancellation

AbortController

Starting from v0.22.0 Axios supports AbortController to cancel requests in a fetch API way:

const controller = new AbortController();

axios
  .get("/foo/bar", {
    signal: controller.signal,
  })
  .then(function (response) {
    //...
  });
// cancel the request
controller.abort();

CancelToken `👎deprecated`

You can also cancel a request using a CancelToken.

The axios cancel token API is based on the withdrawn cancellable promises proposal.

This API is deprecated since v0.22.0 and shouldn't be used in new projects

You can create a cancel token using the CancelToken.source factory as shown below:

const CancelToken = axios.CancelToken;
const source = CancelToken.source();

axios
  .get("/user/12345", {
    cancelToken: source.token,
  })
  .catch(function (thrown) {
    if (axios.isCancel(thrown)) {
      console.log("Request canceled", thrown.message);
    } else {
      // handle error
    }
  });

axios.post(
  "/user/12345",
  {
    name: "new name",
  },
  {
    cancelToken: source.token,
  },
);

// cancel the request (the message parameter is optional)
source.cancel("Operation canceled by the user.");

You can also create a cancel token by passing an executor function to the CancelToken constructor:

const CancelToken = axios.CancelToken;
let cancel;

axios.get("/user/12345", {
  cancelToken: new CancelToken(function executor(c) {
    // An executor function receives a cancel function as a parameter
    cancel = c;
  }),
});

// cancel the request
cancel();

Note: you can cancel several requests with the same cancel token/abort controller. If a cancellation token is already cancelled at the moment of starting an Axios request, then the request is cancelled immediately, without any attempts to make a real request.

During the transition period, you can use both cancellation APIs, even for the same request:

Using `application/x-www-form-urlencoded` format

URLSearchParams

By default, axios serializes JavaScript objects to JSON. To send data in the application/x-www-form-urlencoded format instead, you can use the URLSearchParams API, which is supported in the vast majority of browsers, and Node starting with v10 (released in 2018).

const params = new URLSearchParams({ foo: "bar" });
params.append("extraparam", "value");
axios.post("/foo", params);

Query string (Older browsers)

For compatibility with very old browsers, there is a polyfill available (make sure to polyfill the global environment).

Alternatively, you can encode data using the qs library:

const qs = require("qs");
axios.post("/foo", qs.stringify({ bar: 123 }));

Or in another way (ES6),

import qs from "qs";
const data = { bar: 123 };
const options = {
  method: "POST",
  headers: { "content-type": "application/x-www-form-urlencoded" },
  data: qs.stringify(data),
  url,
};
axios(options);

Older Node.js versions

For older Node.js engines, you can use the querystring module as follows:

const querystring = require("querystring");
axios.post("https://something.com/", querystring.stringify({ foo: "bar" }));

You can also use the qs library.

Note: The qs library is preferable if you need to stringify nested objects, as the querystring method has known issues with that use case.

🆕 Automatic serialization to URLSearchParams

Axios will automatically serialize the data object to urlencoded format if the content-type header is set to "application/x-www-form-urlencoded".

const data = {
  x: 1,
  arr: [1, 2, 3],
  arr2: [1, [2], 3],
  users: [
    { name: "Peter", surname: "Griffin" },
    { name: "Thomas", surname: "Anderson" },
  ],
};

await axios.postForm("https://postman-echo.com/post", data, {
  headers: { "content-type": "application/x-www-form-urlencoded" },
});

The server will handle it as:

  {
    x: '1',
    'arr[]': [ '1', '2', '3' ],
    'arr2[0]': '1',
    'arr2[1][0]': '2',
    'arr2[2]': '3',
    'arr3[]': [ '1', '2', '3' ],
    'users[0][name]': 'Peter',
    'users[0][surname]': 'griffin',
    'users[1][name]': 'Thomas',
    'users[1][surname]': 'Anderson'
  }

If your backend body-parser (like body-parser of express.js) supports nested objects decoding, you will get the same object on the server-side automatically

const app = express();

app.use(bodyParser.urlencoded({ extended: true })); // support encoded bodies

app.post("/", function (req, res, next) {
  // echo body as JSON
  res.send(JSON.stringify(req.body));
});

server = app.listen(3000);

Using `multipart/form-data` format

FormData

To send the data as a multipart/form-data you need to pass a formData instance as a payload. Setting the Content-Type header is not required as Axios guesses it based on the payload type.

const formData = new FormData();
formData.append("foo", "bar");

axios.post("https://httpbin.org/post", formData);

In node.js, you can use the form-data library as follows:

const FormData = require("form-data");

const form = new FormData();
form.append("my_field", "my value");
form.append("my_buffer", Buffer.alloc(10));
form.append("my_file", fs.createReadStream("/foo/bar.jpg"));

axios.post("https://example.com", form);

🆕 Automatic serialization to FormData

Starting from v0.27.0, Axios supports automatic object serialization to a FormData object if the request Content-Type header is set to multipart/form-data.

The following request will submit the data in a FormData format (Browser & Node.js):

import axios from "axios";

axios
  .post(
    "https://httpbin.org/post",
    { x: 1 },
    {
      headers: {
        "Content-Type": "multipart/form-data",
      },
    },
  )
  .then(({ data }) => console.log(data));

In the node.js build, the (form-data) polyfill is used by default.

You can overload the FormData class by setting the env.FormData config variable, but you probably won't need it in most cases:

const axios = require("axios");
var FormData = require("form-data");

axios
  .post(
    "https://httpbin.org/post",
    { x: 1, buf: Buffer.alloc(10) },
    {
      headers: {
        "Content-Type": "multipart/form-data",
      },
    },
  )
  .then(({ data }) => console.log(data));

Axios FormData serializer supports some special endings to perform the following operations:

{} - serialize the value with JSON.stringify
[] - unwrap the array-like object as separate fields with the same key

Note: unwrap/expand operation will be used by default on arrays and FileList objects

FormData serializer supports additional options via config.formSerializer: object property to handle rare cases:

visitor: Function - user-defined visitor function that will be called recursively to serialize the data object to a FormData object by following custom rules.
dots: boolean = false - use dot notation instead of brackets to serialize arrays and objects;
metaTokens: boolean = true - add the special ending (e.g user{}: '{"name": "John"}') in the FormData key. The back-end body-parser could potentially use this meta-information to automatically parse the value as JSON.
indexes: null|false|true = false - controls how indexes will be added to unwrapped keys of flat array-like objects.
- null - don't add brackets (arr: 1, arr: 2, arr: 3)
- false(default) - add empty brackets (arr[]: 1, arr[]: 2, arr[]: 3)
- true - add brackets with indexes (arr[0]: 1, arr[1]: 2, arr[2]: 3)

Let's say we have an object like this one:

const obj = {
  x: 1,
  arr: [1, 2, 3],
  arr2: [1, [2], 3],
  users: [
    { name: "Peter", surname: "Griffin" },
    { name: "Thomas", surname: "Anderson" },
  ],
  "obj2{}": [{ x: 1 }],
};

The following steps will be executed by the Axios serializer internally:

const formData = new FormData();
formData.append("x", "1");
formData.append("arr[]", "1");
formData.append("arr[]", "2");
formData.append("arr[]", "3");
formData.append("arr2[0]", "1");
formData.append("arr2[1][0]", "2");
formData.append("arr2[2]", "3");
formData.append("users[0][name]", "Peter");
formData.append("users[0][surname]", "Griffin");
formData.append("users[1][name]", "Thomas");
formData.append("users[1][surname]", "Anderson");
formData.append("obj2{}", '[{"x":1}]');

Axios supports the following shortcut methods: postForm, putForm, patchForm which are just the corresponding http methods with the Content-Type header preset to multipart/form-data.

Files Posting

You can easily submit a single file:

await axios.postForm("https://httpbin.org/post", {
  myVar: "foo",
  file: document.querySelector("#fileInput").files[0],
});

or multiple files as multipart/form-data:

await axios.postForm("https://httpbin.org/post", {
  "files[]": document.querySelector("#fileInput").files,
});

FileList object can be passed directly:

await axios.postForm(
  "https://httpbin.org/post",
  document.querySelector("#fileInput").files,
);

All files will be sent with the same field names: files[].

🆕 HTML Form Posting (browser)

Pass an HTML Form element as a payload to submit it as multipart/form-data content.

await axios.postForm(
  "https://httpbin.org/post",
  document.querySelector("#htmlForm"),
);

FormData and HTMLForm objects can also be posted as JSON by explicitly setting the Content-Type header to application/json:

await axios.post(
  "https://httpbin.org/post",
  document.querySelector("#htmlForm"),
  {
    headers: {
      "Content-Type": "application/json",
    },
  },
);

For example, the Form

<form id="form">
  <input type="text" name="foo" value="1" />
  <input type="text" name="deep.prop" value="2" />
  <input type="text" name="deep prop spaced" value="3" />
  <input type="text" name="baz" value="4" />
  <input type="text" name="baz" value="5" />

  <select name="user.age">
    <option value="value1">Value 1</option>
    <option value="value2" selected>Value 2</option>
    <option value="value3">Value 3</option>
  </select>

  <input type="submit" value="Save" />
</form>

will be submitted as the following JSON object:

{
  "foo": "1",
  "deep": {
    "prop": {
      "spaced": "3"
    }
  },
  "baz": [
    "4",
    "5"
  ],
  "user": {
    "age": "value2"
  }
}

Sending Blobs/Files as JSON (base64) is not currently supported.

🆕 Progress capturing

Axios supports both browser and node environments to capture request upload/download progress. The frequency of progress events is forced to be limited to 3 times per second.

await axios.post(url, data, {
  onUploadProgress: function (axiosProgressEvent) {
    /*{
      loaded: number;
      total?: number;
      progress?: number; // in range [0..1]
      bytes: number; // how many bytes have been transferred since the last trigger (delta)
      estimated?: number; // estimated time in seconds
      rate?: number; // upload speed in bytes
      upload: true; // upload sign
    }*/
  },

  onDownloadProgress: function (axiosProgressEvent) {
    /*{
      loaded: number;
      total?: number;
      progress?: number;
      bytes: number;
      estimated?: number;
      rate?: number; // download speed in bytes
      download: true; // download sign
    }*/
  },
});

You can also track stream upload/download progress in node.js:

const { data } = await axios.post(SERVER_URL, readableStream, {
  onUploadProgress: ({ progress }) => {
    console.log((progress * 100).toFixed(2));
  },

  headers: {
    "Content-Length": contentLength,
  },

  maxRedirects: 0, // avoid buffering the entire stream
});

Note: Capturing FormData upload progress is not currently supported in node.js environments.

⚠️ Warning It is recommended to disable redirects by setting maxRedirects: 0 to upload the stream in the node.js environment, as the follow-redirects package will buffer the entire stream in RAM without following the "backpressure" algorithm.

🆕 Rate limiting

Download and upload rate limits can only be set for the http adapter (node.js):

const { data } = await axios.post(LOCAL_SERVER_URL, myBuffer, {
  onUploadProgress: ({ progress, rate }) => {
    console.log(
      `Upload [${(progress * 100).toFixed(2)}%]: ${(rate / 1024).toFixed(2)}KB/s`,
    );
  },

  maxRate: [100 * 1024], // 100KB/s limit
});

🆕 AxiosHeaders

Axios has its own AxiosHeaders class to manipulate headers using a Map-like API that guarantees caseless work. Although HTTP is case-insensitive in headers, Axios will retain the case of the original header for stylistic reasons and as a workaround when servers mistakenly consider the header's case. The old approach of directly manipulating the headers object is still available, but deprecated and not recommended for future usage.

Working with headers

An AxiosHeaders object instance can contain different types of internal values. that control setting and merging logic. The final headers object with string values is obtained by Axios by calling the toJSON method.

Note: By JSON here we mean an object consisting only of string values intended to be sent over the network.

The header value can be one of the following types:

string - normal string value that will be sent to the server
null - skip header when rendering to JSON
false - skip header when rendering to JSON, additionally indicates that set method must be called with rewrite option set to true to overwrite this value (Axios uses this internally to allow users to opt out of installing certain headers like User-Agent or Content-Type)
undefined - value is not set

Note: The header value is considered set if it is not equal to undefined.

The headers object is always initialized inside interceptors and transformers:

axios.interceptors.request.use((request: InternalAxiosRequestConfig) => {
  request.headers.set("My-header", "value");

  request.headers.set({
    "My-set-header1": "my-set-value1",
    "My-set-header2": "my-set-value2",
  });

  request.headers.set("User-Agent", false); // disable subsequent setting the header by Axios

  request.headers.setContentType("text/plain");

  request.headers["My-set-header2"] = "newValue"; // direct access is deprecated

  return request;
});

You can iterate over an AxiosHeaders instance using a for...of statement:

const headers = new AxiosHeaders({
  foo: "1",
  bar: "2",
  baz: "3",
});

for (const [header, value] of headers) {
  console.log(header, value);
}

// foo 1
// bar 2
// baz 3

new AxiosHeaders(headers?)

Constructs a new AxiosHeaders instance.

constructor(headers?: RawAxiosHeaders | AxiosHeaders | string);

If the headers object is a string, it will be parsed as RAW HTTP headers.

const headers = new AxiosHeaders(`
Host: www.bing.com
User-Agent: curl/7.54.0
Accept: */*`);

console.log(headers);

// Object [AxiosHeaders] {
//   host: 'www.bing.com',
//   'user-agent': 'curl/7.54.0',
//   accept: '*/*'
// }

AxiosHeaders#set

set(headerName, value: Axios, rewrite?: boolean);
set(headerName, value, rewrite?: (this: AxiosHeaders, value: string, name: string, headers: RawAxiosHeaders) => boolean);
set(headers?: RawAxiosHeaders | AxiosHeaders | string, rewrite?: boolean);

The rewrite argument controls the overwriting behavior:

false - do not overwrite if the header's value is set (is not undefined)
undefined (default) - overwrite the header unless its value is set to false
true - rewrite anyway

The option can also accept a user-defined function that determines whether the value should be overwritten or not.

Returns this.

AxiosHeaders#get(header)

  get(headerName: string, matcher?: true | AxiosHeaderMatcher): AxiosHeaderValue;
  get(headerName: string, parser: RegExp): RegExpExecArray | null;

Returns the internal value of the header. It can take an extra argument to parse the header's value with RegExp.exec, matcher function or internal key-value parser.

const headers = new AxiosHeaders({
  "Content-Type": "multipart/form-data; boundary=Asrf456BGe4h",
});

console.log(headers.get("Content-Type"));
// multipart/form-data; boundary=Asrf456BGe4h

console.log(headers.get("Content-Type", true)); // parse key-value pairs from a string separated with \s,;= delimiters:
// [Object: null prototype] {
//   'multipart/form-data': undefined,
//    boundary: 'Asrf456BGe4h'
// }

console.log(
  headers.get("Content-Type", (value, name, headers) => {
    return String(value).replace(/a/g, "ZZZ");
  }),
);
// multipZZZrt/form-dZZZtZZZ; boundZZZry=Asrf456BGe4h

console.log(headers.get("Content-Type", /boundary=(\w+)/)?.[0]);
// boundary=Asrf456BGe4h

Returns the value of the header.

AxiosHeaders#has(header, matcher?)

has(header: string, matcher?: AxiosHeaderMatcher): boolean;

Returns true if the header is set (has no undefined value).

AxiosHeaders#delete(header, matcher?)

delete(header: string | string[], matcher?: AxiosHeaderMatcher): boolean;

Returns true if at least one header has been removed.

AxiosHeaders#clear(matcher?)

clear(matcher?: AxiosHeaderMatcher): boolean;

Removes all headers. Unlike the delete method matcher, this optional matcher will be used to match against the header name rather than the value.

const headers = new AxiosHeaders({
  foo: "1",
  "x-foo": "2",
  "x-bar": "3",
});

console.log(headers.clear(/^x-/)); // true

console.log(headers.toJSON()); // [Object: null prototype] { foo: '1' }

Returns true if at least one header has been cleared.

AxiosHeaders#normalize(format);

If the headers object was changed directly, it can have duplicates with the same name but in different cases. This method normalizes the headers object by combining duplicate keys into one. Axios uses this method internally after calling each interceptor. Set format to true for converting header names to lowercase and capitalizing the initial letters (cOntEnt-type => Content-Type)

const headers = new AxiosHeaders({
  foo: "1",
});

headers.Foo = "2";
headers.FOO = "3";

console.log(headers.toJSON()); // [Object: null prototype] { foo: '1', Foo: '2', FOO: '3' }
console.log(headers.normalize().toJSON()); // [Object: null prototype] { foo: '3' }
console.log(headers.normalize(true).toJSON()); // [Object: null prototype] { Foo: '3' }

Returns this.

AxiosHeaders#concat(...targets)

concat(...targets: Array<AxiosHeaders | RawAxiosHeaders | string | undefined | null>): AxiosHeaders;

Merges the instance with targets into a new AxiosHeaders instance. If the target is a string, it will be parsed as RAW HTTP headers.

Returns a new AxiosHeaders instance.

AxiosHeaders#toJSON(asStrings?)

toJSON(asStrings?: boolean): RawAxiosHeaders;

Resolve all internal header values into a new null prototype object. Set asStrings to true to resolve arrays as a string containing all elements, separated by commas.

AxiosHeaders.from(thing?)

from(thing?: AxiosHeaders | RawAxiosHeaders | string): AxiosHeaders;

Returns a new AxiosHeaders instance created from the raw headers passed in, or simply returns the given headers object if it's an AxiosHeaders instance.

AxiosHeaders.concat(...targets)

concat(...targets: Array<AxiosHeaders | RawAxiosHeaders | string | undefined | null>): AxiosHeaders;

Returns a new AxiosHeaders instance created by merging the target objects.

Shortcuts

The following shortcuts are available:

setContentType, getContentType, hasContentType
setContentLength, getContentLength, hasContentLength
setAccept, getAccept, hasAccept
setUserAgent, getUserAgent, hasUserAgent
setContentEncoding, getContentEncoding, hasContentEncoding

🔥 Fetch adapter

Fetch adapter was introduced in v1.7.0. By default, it will be used if xhr and http adapters are not available in the build, or not supported by the environment. To use it by default, it must be selected explicitly:

const { data } = axios.get(url, {
  adapter: "fetch", // by default ['xhr', 'http', 'fetch']
});

You can create a separate instance for this:

const fetchAxios = axios.create({
  adapter: "fetch",
});

const { data } = fetchAxios.get(url);

The adapter supports the same functionality as the xhr adapter, including upload and download progress capturing. Also, it supports additional response types such as stream and formdata (if supported by the environment).

🔥 Custom fetch

Starting from v1.12.0, you can customize the fetch adapter to use a custom fetch API instead of environment globals. You can pass a custom fetch function, Request, and Response constructors via env config. This can be helpful in case of custom environments & app frameworks.

Also, when using a custom fetch, you may need to set custom Request and Response too. If you don't set them, global objects will be used. If your custom fetch api does not have these objects, and the globals are incompatible with a custom fetch, you must disable their use inside the fetch adapter by passing null.

Note: Setting Request & Response to null will make it impossible for the fetch adapter to capture the upload & download progress.

Basic example:

import customFetchFunction from "customFetchModule";

const instance = axios.create({
  adapter: "fetch",
  onDownloadProgress(e) {
    console.log("downloadProgress", e);
  },
  env: {
    fetch: customFetchFunction,
    Request: null, // undefined -> use the global constructor
    Response: null,
  },
});

🔥 Using with Tauri

A minimal example of setting up Axios for use in a Tauri app with a platform fetch function that ignores CORS policy for requests.

import { fetch } from "@tauri-apps/plugin-http";
import axios from "axios";

const instance = axios.create({
  adapter: "fetch",
  onDownloadProgress(e) {
    console.log("downloadProgress", e);
  },
  env: {
    fetch,
  },
});

const { data } = await instance.get("https://google.com");

🔥 Using with SvelteKit

SvelteKit framework has a custom implementation of the fetch function for server rendering (so called load functions), and also uses relative paths, which makes it incompatible with the standard URL API. So, Axios must be configured to use the custom fetch API:

export async function load({ fetch }) {
  const { data: post } = await axios.get(
    "https://jsonplaceholder.typicode.com/posts/1",
    {
      adapter: "fetch",
      env: {
        fetch,
        Request: null,
        Response: null,
      },
    },
  );

  return { post };
}

🔥 HTTP2

In version 1.13.0, experimental HTTP2 support was added to the http adapter. The httpVersion option is now available to select the protocol version used. Additional native options for the internal session.request() call can be passed via the http2Options config. This config also includes the custom sessionTimeout parameter, which defaults to 1000ms.

const form = new FormData();

form.append("foo", "123");

const { data, headers, status } = await axios.post(
  "https://httpbin.org/post",
  form,
  {
    httpVersion: 2,
    http2Options: {
      // rejectUnauthorized: false,
      // sessionTimeout: 1000
    },
    onUploadProgress(e) {
      console.log("upload progress", e);
    },
    onDownloadProgress(e) {
      console.log("download progress", e);
    },
    responseType: "arraybuffer",
  },
);

Semver

Since Axios has reached a v.1.0.0 we will fully embrace semver as per the spec here

Promises

axios depends on a native ES6 Promise implementation to be supported. If your environment doesn't support ES6 Promises, you can polyfill.

TypeScript

axios includes TypeScript definitions and a type guard for axios errors.

let user: User = null;
try {
  const { data } = await axios.get("/user?ID=12345");
  user = data.userDetails;
} catch (error) {
  if (axios.isAxiosError(error)) {
    handleAxiosError(error);
  } else {
    handleUnexpectedError(error);
  }
}

Because axios dual publishes with an ESM default export and a CJS module.exports, there are some caveats. The recommended setting is to use "moduleResolution": "node16" (this is implied by "module": "node16"). Note that this requires TypeScript 4.7 or greater. If use ESM, your settings should be fine. If you compile TypeScript to CJS and you can’t use "moduleResolution": "node 16", you have to enable esModuleInterop. If you use TypeScript to type check CJS JavaScript code, your only option is to use "moduleResolution": "node16".

You can also create a custom instance with typed interceptors:

import axios, { AxiosInstance, InternalAxiosRequestConfig } from "axios";

const apiClient: AxiosInstance = axios.create({
  baseURL: "https://api.example.com",
  timeout: 10000,
});

apiClient.interceptors.request.use((config: InternalAxiosRequestConfig) => {
  // Add auth token
  return config;
});

Online one-click setup

You can use Gitpod, an online IDE(which is free for Open Source) for contributing or running the examples online.

Resources

Credits

axios is heavily inspired by the $http service provided in AngularJS. Ultimately axios is an effort to provide a standalone $http-like service for use outside of AngularJS.