Read env variables in React bundled with Spring Boot

Question

I have a Spring Boot application with a bundled React frontend. It's configured with maven frontend plugin to build the react app and put it in the /static so it is served by Spring Boot. Everything is wrapped in a single.jar and deployed to a k8s cluster where the env variables are being handled separately and read by the Spring Boot.

Now, I have to add an API key as a env variable to be read by the React frontend.

As far as I've figured, I can't use .env files since it's not an independent React deployment and won't be seen by the frontend. The only thing I can think of is to pass it to Spring Boot and then expose it via an endpoint to the frontend.

Am I missing something, is there a way to use .env files in this setup, or some other way that is better for this use case?

Answer 1

This was eventually resolved by setting it as an environment variable for the Spring Boot application which then read that value and exposed it via a dedicated controller on a secured endpoint. The react app would then simply fetch it via a GET request from the controller.