How does one set global headers in axios?

In the process of making network requests with Axios, setting global headers is a common requirement. This helps ensure that specific information, such as an authentication token, is sent with every request. Setting global headers in Axios can be achieved by modifying the default configuration of Axios. Below are the steps and examples for setting global headers:

Step 1: Import the Axios Library

First, ensure that the Axios library is installed and imported in your project.

javascript
import axios from 'axios';

Step 2: Set Global Headers

Use axios.defaults.headers.common or axios.defaults.headers to set your global headers. For example, if you want to add an authentication token to all requests, you can do the following:

javascript
axios.defaults.headers.common['Authorization'] = 'Bearer YOUR_TOKEN';

Alternatively, if you want to set the content type specifically for POST requests, you can use:

javascript
axios.defaults.headers.post['Content-Type'] = 'application/json';

Example

Suppose we need to add a JWT (JSON Web Tokens) authentication token to all requests in a user authentication application. Here is the code for setting global headers:

javascript
import axios from 'axios';

// Assume the token is obtained from environment variables or elsewhere
const userToken = 'your_jwt_token_here';

// Set global headers
axios.defaults.headers.common['Authorization'] = `Bearer ${userToken}`;

// Now, every request made with Axios will include this authentication header

Notes

• Ensure that you obtain the necessary header values before setting global headers, such as obtaining a token after user login.
• For different request types (e.g., GET, POST), you can set different headers.
• Remember that modifications to global headers may affect all requests in your application, so ensure this is the intended behavior.

By following these methods, you can easily set global headers for your Axios requests, which is very useful for handling common scenarios such as authentication.