Скачать или смотреть How to Fix CORS Issues When Setting Headers with Axios in React and Express

Discover effective strategies to solve `CORS` problems while setting headers in your React-Express application using Axios. This guide provides step-by-step instructions to ensure your authorization headers are properly configured.
---
This video is based on the question https://stackoverflow.com/q/67236750/ asked by the user '7sne' ( https://stackoverflow.com/u/13101986/ ) and on the answer https://stackoverflow.com/a/67236958/ provided by the user 'eminsh' ( https://stackoverflow.com/u/9528561/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: React - can't set headers with axios

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Solving CORS Issues with Axios in React and Express

When building a web application that leverages React and Express, you may face difficulties when trying to set headers—specifically, issues related to Cross-Origin Resource Sharing (CORS). If you've been struggling to set headers with JWT tokens using Axios, you're not alone. In this guide, we'll dive into the problem, explore potential causes, and provide clear solutions to ensure you're able to manage your headers effectively.

Understanding the Problem: CORS and Headers

CORS is a security feature implemented in web browsers that prevents malicious websites from making requests to your server without explicit permission. When building an API with Express and a frontend with React, it's common to encounter CORS-related issues when trying to authenticate users. The problem often manifests in the browser console as CORS errors, which indicate that the server is rejecting the request due to missing or disallowed headers.

In your case, it seems you've set up an authorization process using JWT tokens but are struggling to include the necessary headers in your Axios requests. Let’s break down a solid solution to ensure that your headers are set correctly.

Step-by-Step Solution

1. Configure Global Axios Instance

To manage global settings for Axios, create an instance of Axios with proper headers. You'll want to include the Bearer token in your global Axios settings.

Here's an example of how to do this:

[[See Video to Reveal this Text or Code Snippet]]

2. Update Your Redux Action

After configuring your Axios instance, you need to utilize it in your Redux actions. Here’s how you can modify your action to leverage the newly created Axios instance for logging in users:

[[See Video to Reveal this Text or Code Snippet]]

3. Server-Side CORS Configuration

Make sure your Express server is set up to allow requests from your frontend. This includes specifying allowed headers and credentials explicitly. Your CORS setup should look something like this:

[[See Video to Reveal this Text or Code Snippet]]

Testing Your Configuration

After implementing the changes above, it’s crucial to test your setup. Open your browser's console and check for any CORS errors when sending requests. If everything is set correctly, you should no longer see headers related issues in your requests.

Conclusion

CORS issues can be tricky, but with careful configuration of both your client-side and server-side code, they can be resolved. Remember to always check if your headers are properly set and if the server allows the necessary CORS configuration. By following the steps outlined in this post, you should be able to include your JWT tokens seamlessly in Axios requests while ensuring a secure and functional connection between your React app and Express API.

For further questions or troubleshooting tips, feel free to leave a comment below!