README.md

react-native-axios-jwt

Store, clear, transmit and automatically refresh JWT authentication tokens in a React Native environment.

Looking for a web alternative? Check out axios-jwt

What does it do?

Applies a request interceptor to your axios instance.

The interceptor automatically adds a header (default: Authorization) with an access token to all requests. It stores accessToken and refreshToken in AsyncStorage and reads them when needed.

It parses the expiration time of your access token and checks to see if it is expired before every request. If it has expired, a request to refresh and store a new access token is automatically performed before the request proceeds.

Installation

1. Install React Native Async Storage

2. Install this library

With npm:

npm install react-native-axios-jwt

With Yarn:

yarn add react-native-axios-jwt

How do I use it?

1. Create an axios instance.
2. Define a token refresh function.
3. Configure the interceptor.
4. Store tokens on login with setAuthTokens function.
5. Clear tokens on logout with clearAuthTokens function.

Applying the interceptor

// api.ts

import axios from 'axios'
import {
  type AuthTokenInterceptorConfig,
  type AuthTokens,
  type TokenRefreshRequest,
  applyAuthTokenInterceptor,
} from 'react-native-axios-jwt'

const BASE_URL = 'https://api.example.com'

// 1. Create an axios instance that you wish to apply the interceptor to
export const axiosInstance = axios.create({
  baseURL: BASE_URL,
})

// 2. Define token refresh function.
// It is an async function that takes a refresh token and returns a promise
// that resolves in fresh access token and refresh token.
// You can also return only an access token in a case when a refresh token stays the same.
const requestRefresh: TokenRefreshRequest = async (
  refreshToken: string,
): Promise<AuthTokens> => {
  // Important! Do NOT use the axios instance that you supplied to applyAuthTokenInterceptor
  // because this will result in an infinite loop when trying to refresh the token.
  // Use the global axios client or a different instance.
  const response = await axios.post(`${BASE_URL}/auth/refresh_token`, {
    token: refreshToken,
  })

  const {
    access_token: newAccessToken,
    refresh_token: newRefreshToken,
  } = response.data

  return {
    accessToken: newAccessToken,
    refreshToken: newAccessToken,
  }
}

const config: AuthTokenInterceptorConfig = {
  requestRefresh,
}

// 3. Add interceptor to your axios instance
applyAuthTokenInterceptor(axiosInstance, config)

Login

// login.ts

import { setAuthTokens } from 'react-native-axios-jwt'

import { axiosInstance } from './api'

// 4. Log in with POST request with the email and password.
// Get access token and refresh token in response.
// Call `setAuthTokens` with the tokens.
const login = async (params: LoginRequestParams): void => {
  const response = await axiosInstance.post('/auth/login', params)

  const {
    access_token: accessToken,
    refresh_token: refreshToken,
  } = response.data

  // Save tokens to AsyncStorage.
  await setAuthTokens({
    accessToken,
    refreshToken,
  })
}

Usage

// usage.ts

import {
  getAccessToken,
  getRefreshToken,
  isLoggedIn,
} from 'react-native-axios-jwt';

// Check if the user is logged in.
if (isLoggedIn()) {
  // Assume the user is logged in because we have a refresh token stored in AsyncStorage.
}

// Use access token.
const doSomethingWithAccessToken = async (): void => {
  const accessToken = await getAccessToken()

  console.log(accessToken)
}

// Use refresh token.
const doSomethingWithRefreshToken = async (): void => {
  const refreshToken = await getRefreshToken()

  console.log(refreshToken)
}

Logout

// logout.ts

import { clearAuthTokens } from 'react-native-axios-jwt'

// 5. Log out by clearing the auth tokens from AsyncStorage.
const logout = async (): void => {
  await clearAuthTokens()
}

Configuration

applyAuthTokenInterceptor(axiosInstance, {
  header = 'Authorization',  // header name
  headerPrefix = 'Bearer ',  // header value prefix
  requestRefresh,  // async function that resolves in fresh access token (and refresh token)
})

Caveats

• Your backend should allow a few seconds of leeway between when the token expires and when it actually becomes unusable.