How to modify axios instance after exported it in ReactJS?

问题

I am using:

axios.defaults.headers.common['Authorization'] = 'Bearer ' + token;

to set header after user make login in application, but when refresh the page this configuration is removed.

I would like to set this configuration for all requests from axios, when user make login.

I got do that setting this configuration manually, putting this line of code before to export axios instance.

Now, I need to set this configuration when user make login. How can I do that?

回答1:

You're probably going to want to write a middleware module to get/set the token in localStorage and apply it to your Axios instance. In the past when I used Axios, I typically did it like this:

import axios from 'axios';
import { API_URL } from '../constants/api';

const API = axios.create({
  baseURL: `${API_URL}`,
  timeout: 10000,
  headers: {
    'Content-Type': 'application/json',
  },
});

API.interceptors.request.use(
  config => {
    const token = sessionStorage.getItem('jwt');

    if (token) {
      config.headers.Authorization = `Bearer ${token}`;
    } else {
      delete API.defaults.headers.common.Authorization;
    }
    return config;
  },

  error => Promise.reject(error)
);

export default API;

You'll need to create functions to get/set the JWT in localStorage, but if you do that, this should work for you. This will fetch the JWT from localStorage before making each request, so it won't break even if the page is refreshed as long as the user has a valid JWT in localStorage.

来源：https://stackoverflow.com/questions/58126608/how-to-modify-axios-instance-after-exported-it-in-reactjs