Скачать или смотреть Resolving NGINX Default 401 Page: How to Return JSON Data Instead of Error Page

Discover how to customize NGINX error responses and return JSON data instead of the default 401 authentication error page in your web applications.
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How to Return JSON Data Instead of NGINX 401 Page on Auth Request

When you’re working with NGINX as a reverse proxy, authenticating requests is a crucial aspect of web applications. However, encountering a standard 401 error page can be frustrating, especially when you want to return meaningful JSON data to the client. This guide will walk you through the problem and the solution to make your application return a beautiful JSON response instead of the default NGINX 401 error page.

The Problem

In your current setup, you have an NGINX configuration that routes requests to your application. When the /auth route encounters an authentication error (i.e., returns a 401 status), NGINX displays its own default 401 error page rather than the custom JSON response you expect. Here is the relevant section of your existing NGINX configuration:

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

Your authentication endpoint simply returns a 401 status:

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

Instead of sending a JSON response, NGINX serves its own styled error page. This is where the confusion lies, and it requires a solution that allows you to send back your JSON data instead.

The Solution: Customizing the NGINX Configuration

The simple solution to this issue is to customize your NGINX configuration to tell it how to handle 401 errors specifically. You can do this by using the error_page directive. Here's how to implement it:

Step-by-step Instructions

Modify Your NGINX Configuration: Add the error_page directive to your /index location block. This directive instructs NGINX to redirect to the /auth endpoint whenever a 401 error occurs.

Here's what you need to add:

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

Testing Your Changes: After saving the configuration, it's essential to test your changes with a request that would trigger the authentication failure. You should see your JSON response instead of the default NGINX error page.

Restart NGINX: Don’t forget to restart NGINX to apply your changes. Depending on your system, this can typically be done via:

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

What Does This Change Do?

With the error_page 401 =401 /auth; configuration in place, when a 401 status is returned from your /auth endpoint, NGINX redirects the response accordingly. It allows NGINX to fetch the content from the /auth location and return it unchanged (with a 401 status), so the client receives your intended JSON response.

Conclusion

By following the outlined steps, you can effectively customize the 401 responses of NGINX to suit your needs, allowing for a more user-friendly and informative response when authentication fails. This method not only enhances the usability of your application but also ensures that clients can handle errors more gracefully with the data they truly need.

If you encounter any further issues, feel free to reach out for assistance or consult the extensive documentation available for NGINX. Happy coding!