List all of your local environment variables.
This simple web app is useful (for me) for testing purposed to easily check if the Pods of a cluster contain the right environment variables.
You DO NOT want this web app in a production environment.
Just run the docker container with the following command
docker run -it --rm -p 8080:80 sebagomez/whistleblower
and then go to http://localhost:8080 to see the variables.